WorldWideScience

Sample records for direct injection engines

  1. Construction of a Direct Water-Injected Two-Stroke Engine for Phased Direct Fuel Injection-High Pressure Charging Investigations

    Science.gov (United States)

    Somsel, James P.

    1998-01-01

    The development of a water injected Orbital Combustion Process (OCP) engine was conducted to assess the viability of using the powerplant for high altitude NASA aircraft and General Aviation (GA) applications. An OCP direct fuel injected, 1.2 liter, three cylinder, two-stroke engine has been enhanced to independently inject water directly into the combustion chamber. The engine currently demonstrates low brake specific fuel consumption capability and an excellent power to weight ratio. With direct water injection, significant improvements can be made to engine power, to knock limits/ignition advance timing, and to engine NO(x) emissions. The principal aim of the testing was to validate a cyclic model developed by the Systems Analysis Branch at NASA Ames Research Center. The work is a continuation of Ames' investigations into a Phased Direct Fuel Injection Engine with High Pressure Charging (PDFI-ITPC).

  2. Optimization of injection law for direct injection diesel engine

    International Nuclear Information System (INIS)

    Feola, M.; Bella, G.; Pelloni, P.; Casoli, P.; Toderi, G.; Cantore, G.

    1992-01-01

    This paper describes how different timing and shape of the injection law can influence pollutant emission of a direct injection diesel engine. The study was carried out making use of a multizone thermodynamic model as regards the closed valve phase, and a filling-emptying one as regards the open valve phase. After being calibrated by comparison with experimental data, the abovementioned model was used for injection law optimization as regards minimum pollutant concentration (NO x and soot) in the exhaust gases with the smallest engine performance reduction possible

  3. COMBUSTION ANALYSIS OF A CNG DIRECT INJECTION SPARK IGNITION ENGINE

    Directory of Open Access Journals (Sweden)

    A. Rashid A. Aziz

    2010-12-01

    Full Text Available An experimental study was carried out on a dedicated compressed natural gas direct injection (CNG-DI engine with a compression ratio (CR of 14 and a central injection system. Several injection timing parameters from early injection timing (300 BTDC to partial direct injection (180 BTDC to full direct injection (120 BTDC were investigated. The 300 BTDC injection timing experiment was carried out to simulate the performance of a port injection engine and the result is used as a benchmark for engine performance. The full DI resulted in a 20% higher performance than the early injection timing for low engine speeds up to 2750 rpm. 180 BTDC injection timing shows the highest performance over an extensive range of engine speed because it has a similar volumetric efficiency to full DI. However, the earlier injection timing allowed for a better air–fuel mixing and gives superior performance for engine speeds above 4500 rpm. The engine performance could be explained by analysis of the heat release rate that shows that at low and intermediate engine speeds of 2000 and 3000, the full DI and partial DI resulted in the fastest heat release rate whereas at a high engine speed of 5000 rpm, the simulated port injection operation resulted in the fastest heat release rate.

  4. Method for operating a spark-ignition, direct-injection internal combustion engine

    Science.gov (United States)

    Narayanaswamy, Kushal; Koch, Calvin K.; Najt, Paul M.; Szekely, Jr., Gerald A.; Toner, Joel G.

    2015-06-02

    A spark-ignition, direct-injection internal combustion engine is coupled to an exhaust aftertreatment system including a three-way catalytic converter upstream of an NH3-SCR catalyst. A method for operating the engine includes operating the engine in a fuel cutoff mode and coincidentally executing a second fuel injection control scheme upon detecting an engine load that permits operation in the fuel cutoff mode.

  5. UV-visible digital imaging of split injection in a Gasoline Direct Injection engine

    Directory of Open Access Journals (Sweden)

    Merola Simona Silvia

    2015-01-01

    Full Text Available Ever tighter limits on pollutant emissions and the need to improve energy conversion efficiency have made the application of gasoline direct injection (GDI feasible for a much wider scale of spark ignition engines. Changing the way fuel is delivered to the engine has thus provided increased flexibility but also challenges, such as higher particulate emissions. Therefore, alternative injection control strategies need to be investigated in order to obtain optimum performance and reduced environmental impact. In this study, experiments were carried out on a single-cylinder GDI optical engine fuelled with commercial gasoline in lean-burn conditions. The single-cylinder was equipped with the head of a commercial turbocharged engine with similar geometrical specifications (bore, stroke, compression ratio and wall guided fuel injection. Optical accessibility was ensured through a conventional elongated hollow Bowditch piston and an optical crown, accommodating a fused-silica window. Experimental tests were performed at fixed engine speed and injection pressure, whereas the injection timing and the number of injections were adjusted to investigate their influence on combustion and emissions. UV-visible digital imaging was applied in order to follow the combustion process, from ignition to the late combustion phase. All the optical data were correlated with thermodynamic analysis and measurements of exhaust emissions. Split injection strategies (i.e. two injections per cycle with respect to single injection increased combustion efficiency and stability thanks to an improvement of fuel air mixing. As a consequence, significant reduction in soot formation and exhaust emission with acceptable penalty in terms of HC and NOx were measured.

  6. Effects of gaseous ammonia direct injection on performance characteristics of a spark-ignition engine

    International Nuclear Information System (INIS)

    Ryu, Kyunghyun; Zacharakis-Jutz, George E.; Kong, Song-Charng

    2014-01-01

    Highlights: • This is the very first study in utilizing direct injection of gaseous ammonia in an SI engine. • Engine combustion using direct injection of gaseous ammonia is proven feasible. • Energy efficiency using ammonia is comparable to that using gasoline. • CO emissions are decreased but emissions of NOx and HC are increased when ammonia is used. - Abstract: The effects of direct injection of gaseous ammonia on the combustion characteristics and exhaust emissions of a spark-ignition engine were investigated. Port-injection gasoline was used to enhance the burning of ammonia that was directly injected into the engine cylinder. Appropriate direct injection strategies were developed to allow ammonia to be used in spark-ignition engines without sacrifice of volumetric efficiency. Experimental results show that with gasoline providing the baseline power of 0.6 kW, total engine power could increase to 2.7 kW when the injection timing of ammonia was advanced to 370 BTDC with injection duration of 22 ms. Engine performance with use of gasoline–ammonia was compared to that with gasoline alone. For operations using gasoline–ammonia, with baseline power from gasoline at 0.6 kW the appropriate ammonia injection timing was found to range from 320 to 370 BTDC for producing 1.5–2.7 kW. The peak pressures were slightly lower than those using gasoline alone because of the lower flame of ammonia, resulting in reduction of cylinder pressure. The brake specific energy consumption (BSEC) with gasoline–ammonia was very similar to that with gasoline alone. Ammonia direct injection caused slight reductions of BSCO for all the loads studied but significantly increased BSHC because of the reduced combustion temperature of ammonia combustion. The use of ammonia resulted in increased NOx emissions because of formation of fuel NOx. Ammonia slip was also detected in the engine exhaust because of incomplete combustion

  7. Design and development of a direct injection system for cryogenic engines

    Science.gov (United States)

    Mutumba, Angela; Cheeseman, Kevin; Clarke, Henry; Wen, Dongsheng

    2018-04-01

    The cryogenic engine has received increasing attention due to its promising potential as a zero-emission engine. In this study, a new robust liquid nitrogen injection system was commissioned and set up to perform high-pressure injections into an open vessel. The system is used for quasi-steady flow tests used for the characterisation of the direct injection process for cryogenic engines. An electro-hydraulic valve actuator provides intricate control of the valve lift, with a minimum cycle time of 3 ms and a frequency of up to 20 Hz. With additional sub-cooling, liquid phase injections from 14 to 94 bar were achieved. Results showed an increase in the injected mass with the increase in pressure, and decrease in temperature. The injected mass was also observed to increases linearly with the valve lift. Better control of the injection process, minimises the number of variables, providing more comparable and repeatable sets of data. Implications of the results on the engine performance were also discussed.

  8. Direct injection of gaseous LPG in a two-stroke SI engine for improved performance

    International Nuclear Information System (INIS)

    Pradeep, V.; Bakshi, Shamit; Ramesh, A.

    2015-01-01

    Improvements in a two-stroke, spark-ignition (2S–SI) engine can be realized by curtailing short-circuiting losses effectively through direct injection of the fuel. Liquefied petroleum gas (LPG) is an alternative transportation fuel that is used in several countries. However, limited information is available on LPG fuelled direct injected engines. Hence, there is a need to study these systems as applied to 2S–SI engines in order to bring out their potential benefits. A manifold injected 2S–SI engine is modified for direct injection of LPG, in gaseous form, from the cylinder head. This engine is evaluated for performance, emission and combustion. Evaluation at various throttle positions and constant speed showed that this system can significantly improve the thermal efficiency and lower the hydrocarbon (HC) emissions. Up to 93% reduction in HC emissions and improved combustion rates are observed compared to the conventional manifold injection system with LPG. CO emissions are higher and peak NO emissions are lower with this system due to the presence of richer in–cylinder trapped mixtures and charge stratification. This system can operate with similar injection timings at different throttle positions which make electronic control simpler. It can work with low injection pressures in the range of 4–5 bars. All these advantages are attractive for commercial viability of this engine. - Highlights: • Energy saving, low pressure, direct gaseous LPG injection in engine. • Significant reduction in HC emissions at all operating conditions. • No significant changes in injection timings for different throttle positions.

  9. Influence of fuel injection pressures on Calophyllum inophyllum methyl ester fuelled direct injection diesel engine

    International Nuclear Information System (INIS)

    Nanthagopal, K.; Ashok, B.; Karuppa Raj, R. Thundil

    2016-01-01

    Highlights: • Effect of injection pressure of Calophyllum inophyllum biodiesel is investigated. • Engine characteristics of 100% Calophyllum inophyllum biodiesel has been performed. • Calophyllum inophyllum is a non-edible source for biodiesel production. • Increase in injection pressure of biodiesel, improves the fuel economy. • Incylinder pressure characteristics of biodiesel follows similar trend as of diesel. - Abstract: The trend of using biodiesels in compression ignition engines have been the focus in recent decades due to the promising environmental factors and depletion of fossil fuel reserves. This work presents the effect of Calophyllum inophyllum methyl ester on diesel engine performance, emission and combustion characteristics at different injection pressures. Experimental investigations with varying injection pressures of 200 bar, 220 bar and 240 bar have been carried out to analyse the parameters like brake thermal efficiency, specific fuel consumption, heat release rate and engine emissions of direct injection diesel engine fuelled with 100% biodiesel and compared with neat diesel. The experimental results revealed that brake specific fuel consumption of C. inophyllum methyl ester fuelled engine has been reduced to a great extent with higher injection pressure. Significant reduction in emissions of unburnt hydrocarbons, carbon monoxide and smoke opacity have been observed during fuel injection of biodiesel at 220 bar compared to other fuel injection pressures. However oxides of nitrogen increased with increase in injection pressures of C. inophyllum methyl ester and are always higher than that of neat diesel. In addition the combustion characteristics of biodiesel at all injection pressures followed a similar trend to that of conventional diesel.

  10. Increasing energy efficiency of a gasoline direct injection engine through optimal synchronization of single or double injection strategies

    International Nuclear Information System (INIS)

    Costa, Michela; Sorge, Ugo; Allocca, Luigi

    2012-01-01

    Highlights: ► Advantages of split injection in a GDI engine are studied through numerical simulation. ► At high load and speed, rich conditions, split injection does not improve engine performance. ► At moderate load and speed, lean conditions, double injection improves charge stratification. ► Optimal double injection increases work, reduces HC and increases NO. - Abstract: The greatest fuel efficiency advantages of gasoline direct injection (GDI) engines are achieved under the so-called mixed mode boosting, where mixture characteristics are properly adapted to the specific working condition. In particular, in the medium range of load and speed, overall lean mixtures are suitable of being used in the so-called direct injection stratified charge operation. Present paper reports the results of numerical optimization analyses aimed at increasing the energetic efficiency of a GDI engine equipped with a high pressure multi-hole injector under both single and double injection events. In moderate-load moderate-speed lean conditions, the single or double injection synchronization in the working cycle is effected through a procedure that couples a 3D numerical model of the in-cylinder processes with an optimization tool. The choice of both the start of the injection events and the time of spark advance is realized to maximize the engine work. The optimal double injection solution is shown to increase the engine energy efficiency with respect to the case injection is realized in one shot, thus confirming that split injections improve the quality of the charge stratification under lean operation. The effect on the major pollutants is also discussed.

  11. Numerical Modeling of a Jet Ignition Direct Injection (JI DI LPG Engine

    Directory of Open Access Journals (Sweden)

    Albert Boretti

    2017-01-01

    Full Text Available The paper presents indirectly validated simulations of the operation of a LPG engine fitted with Direct Injection (DI and Jet Ignition (JI. It is demonstrated that the engine may have diesel like efficiencies and load control by quantity of fuel injected.  As the liquid propane quickly evaporates after injection in the main chamber, the main chamber mixture may be much closer to stoichiometry than a diesel for a better specific power at low engine speeds. This design also works at the high engine speeds impossible for the diesel, as combustion within the main chamber is controlled by the turbulent mixing rather than the vaporization and diffusion processes of the injected fuel of the diesel. 

  12. Direct injection of a diesel-butane blend in a heavy duty engine

    NARCIS (Netherlands)

    Leermakers, C.A.J.; van den Berge, B.; Luijten, C.C.M.; Somers, L.M.T.; Jaasma, S.A.M.; Goey, de L.P.H.

    2011-01-01

    LPG (Liquefied Petroleum Gas) has for long been used in passenger cars. Presently, LPG sup-ply systems have also attracted considerable at-tention for heavy duty use. LPG can be applied in these engines combining port fuel injected LPG with a direct injection of diesel. These engines equipped with a

  13. Experimental optimization of a direct injection homogeneous charge compression ignition gasoline engine using split injections with fully automated microgenetic algorithms

    Energy Technology Data Exchange (ETDEWEB)

    Canakci, M. [Kocaeli Univ., Izmit (Turkey); Reitz, R.D. [Wisconsin Univ., Dept. of Mechanical Engineering, Madison, WI (United States)

    2003-03-01

    Homogeneous charge compression ignition (HCCI) is receiving attention as a new low-emission engine concept. Little is known about the optimal operating conditions for this engine operation mode. Combustion under homogeneous, low equivalence ratio conditions results in modest temperature combustion products, containing very low concentrations of NO{sub x} and particulate matter (PM) as well as providing high thermal efficiency. However, this combustion mode can produce higher HC and CO emissions than those of conventional engines. An electronically controlled Caterpillar single-cylinder oil test engine (SCOTE), originally designed for heavy-duty diesel applications, was converted to an HCCI direct injection (DI) gasoline engine. The engine features an electronically controlled low-pressure direct injection gasoline (DI-G) injector with a 60 deg spray angle that is capable of multiple injections. The use of double injection was explored for emission control and the engine was optimized using fully automated experiments and a microgenetic algorithm optimization code. The variables changed during the optimization include the intake air temperature, start of injection timing and the split injection parameters (per cent mass of fuel in each injection, dwell between the pulses). The engine performance and emissions were determined at 700 r/min with a constant fuel flowrate at 10 MPa fuel injection pressure. The results show that significant emissions reductions are possible with the use of optimal injection strategies. (Author)

  14. Energy efficiency of a direct-injection internal combustion engine with high-pressure methanol steam reforming

    International Nuclear Information System (INIS)

    Poran, Arnon; Tartakovsky, Leonid

    2015-01-01

    This article discusses the concept of a direct-injection ICE (internal combustion engine) with thermo-chemical recuperation realized through SRM (steam reforming of methanol). It is shown that the energy required to compress the reformate gas prior to its injection into the cylinder is substantial and has to be accounted for. Results of the analysis prove that the method of reformate direct-injection is unviable when the reforming is carried-out under atmospheric pressure. To reduce the energy penalty resulted from the gas compression, it is suggested to implement a high-pressure reforming process. Effects of the injection timing and the injector's flow area on the ICE-SRM system's fuel conversion efficiency are studied. The significance of cooling the reforming products prior to their injection into the engine-cylinder is demonstrated. We show that a direct-injection ICE with high-pressure SRM is feasible and provides a potential for significant efficiency improvement. Development of injectors with greater flow area shall contribute to further efficiency improvements. - Highlights: • Energy needed to compress the reformate is substantial and has to be accounted for. • Reformate direct-injection is unviable if reforming is done at atmospheric pressure. • Direct-injection engine with high-pressure methanol reforming is feasible. • Efficiency improvement by 12–14% compared with a gasoline-fed engine was shown

  15. Performance Characteristics Comparison of CNG Port and CNG Direct Injection in Spark Ignition Engine

    Directory of Open Access Journals (Sweden)

    Rajesh Patel

    2018-03-01

    Full Text Available A comparative performance analysis is being carried out on a four cylinder, four stroke cycle, spark ignition engine having displacement volume 1297cc. The cylinder head of original gasoline based engine was modified by drilling holes from upper surfaces of head to individual combustion chamber to convert the engine in a CNG direct injection engine. The CNG port injection (CNG-PI system and CNG direct injection (CNG-DI system were incorporated with the single engine.  The engine was retrofitted to run on both CNG-PI and CNG-DI system alternately with common CNG tank and other engine loading and measurement system. The engine was equipped with electrical dynamometer having rheostat type loading. The CNG direct injection system was incorporated with various sensors and engine ECU. The operating parameters can be obtained on computer screen by loading the computer with engine through switch box. The engine was run over the speed range of 1000 rpm to 3000 rpm with incremental speed of 300 rpm. The performance parameters were calculated from observations and recorded for both CNG-PI and CNG-DI system. The experimental investigation exhibits that, the average 7-8% reduction in BSFC while the engine was running with CNG-DI system as compared to that of CNG-PI system. Also the engine produced 8-9% higher brake torque and hence higher brake power. The engine gives 6-7% higher brake thermal efficiency with CNG-DI system as compared to CNG-PI system.

  16. Computer simulation of a turbocharged direct injection diesel engine

    International Nuclear Information System (INIS)

    Bannikiv, M.G.; Saeed, M.

    2005-01-01

    Engine model described in this paper was developed to investigate the working process and overall performance of a heavy-duty turbocharged direct injection diesel engine. The primary focus was made on exploring the methods of engine power boosting, study of engine behaviour after their implementation and optimization of all engine parameters. Engine model is classified as on zone, zero dimensional and phenomenological and includes submodels for in cylinder heat transfer, heat release and valve flow processes. Turbocharger model is developed using the available maps of turbine and compressor. The whole engine system is zero dimensional and the different system components are liked by means of mean values for mass flow, temperatures, pressures and gas composition. NASA polynomials are used for computing thermal properties of mixture of gasses. Model is flexible and easy to accommodate additional submodels of various physical phenomena such as emission formation, fuel injection, ignition delay period calculation etc. The software is developed in MATLAB. Software was used to analyse an evaporative cooling of boost air as a method of an increase of engine power. Results of simulation are provided in the paper. For the augmented engine, mechanical and thermal loads required for the strength analyses were obtained. (author)

  17. Numerical Study on Fan Spray for Gasoline Direct Injection Engines

    OpenAIRE

    Shirabe, Naotaka; Sato, Takaaki; Murase, Eiichi

    2003-01-01

    In gasoline direct injection engines, it is important to optimize fuel spray characteristics, which strongly affect stratified combustion process. Spray simulation is expected as a tool for optimizing the nozzle design. Conventional simulation method, how

  18. Modelling the effect of injection pressure on heat release parameters and nitrogen oxides in direct injection diesel engines

    Directory of Open Access Journals (Sweden)

    Yüksek Levent

    2014-01-01

    Full Text Available Investigation and modelling the effect of injection pressure on heat release parameters and engine-out nitrogen oxides are the main aim of this study. A zero-dimensional and multi-zone cylinder model was developed for estimation of the effect of injection pressure rise on performance parameters of diesel engine. Double-Wiebe rate of heat release global model was used to describe fuel combustion. extended Zeldovich mechanism and partial equilibrium approach were used for modelling the formation of nitrogen oxides. Single cylinder, high pressure direct injection, electronically controlled, research engine bench was used for model calibration. 1000 and 1200 bars of fuel injection pressure were investigated while injection advance, injected fuel quantity and engine speed kept constant. The ignition delay of injected fuel reduced 0.4 crank angle with 1200 bars of injection pressure and similar effect observed in premixed combustion phase duration which reduced 0.2 crank angle. Rate of heat release of premixed combustion phase increased 1.75 % with 1200 bar injection pressure. Multi-zone cylinder model showed good agreement with experimental in-cylinder pressure data. Also it was seen that the NOx formation model greatly predicted the engine-out NOx emissions for both of the operation modes.

  19. Effects of pilot injection timing and EGR on a modern V6 common rail direct injection diesel engine

    Science.gov (United States)

    Rosli Abdullah, Nik; Mamat, Rizalman; Wyszynski, Miroslaw L.; Tsolakis, Anthanasios; Xu, Hongming

    2013-12-01

    Nitric oxide and smoke emissions in diesel engine can be controlled by optimising the air/fuel mixture. Early injection produces premixed charge resulted in simultaneous NOx and smoke emissions reduction. However, there could be an increase in hydrocarbons and CO emissions due to fuel impinged to the cylinder wall. The focus of the present work is to investigate the effects of a variation of pilot injection timing with EGR to NOx and smoke level on a modern V6 common rail direct injection. This study is carried out at two different engine load conditions of 30 Nm and 55 Nm, at constant engine speed of 2000 rpm. The results show that the early pilot injection timing contributed to the lower smoke level and higher NOx emissions. The higher level of NOx is due to higher combustion temperatures resulting from the complete combustion. Meanwhile, the lower smoke level is due to complete fuel combustion and soot oxidation. The early pilot injection timing produces an intermediate main ignition delay which also contributed to complete combustion. The formation of smoke is higher at a high engine load compared with low engine load due to the higher amount of fuel being injected.

  20. Study of In-Cylinder Reactions of High Power-Density Direct Injection Diesel Engines

    National Research Council Canada - National Science Library

    Jansons, M

    2004-01-01

    Direct-injection (DI) Diesel or compression-ignition (CI) engine combustion process is investigated when new design and operational strategies are employed in order to achieve a high power-density (HPD) engine...

  1. Influence of narrow fuel spray angle and split injection strategies on combustion efficiency and engine performance in a common rail direct injection diesel engine

    Directory of Open Access Journals (Sweden)

    Raouf Mobasheri

    2017-03-01

    Full Text Available Direct injection diesel engines have been widely used in transportation and stationary power systems because of their inherent high thermal efficiency. On the other hand, emission regulations such as NOx and particulates have become more stringent from the standpoint of preserving the environment in recent years. In this study, previous results of multiple injection strategies have been further investigated to analyze the effects of narrow fuel spray angle on optimum multiple injection schemes in a heavy duty common rail direct injection diesel engine. An advanced computational fluid dynamics simulation has been carried out on a Caterpillar 3401 diesel engine for a conventional part load condition in 1600 r/min at two exhaust gas recirculation rates. A good agreement of calculated and measured in-cylinder pressure, heat release rate and pollutant formation trends was obtained under various operating points. Three different included spray angles have been studied in comparison with the traditional spray injection angle. The results show that spray targeting is very effective for controlling the in-cylinder mixture distributions especially when it accompanied with various injection strategies. It was found that the optimum engine performance for simultaneous reduction of soot and NOx emissions was achieved with 105° included spray angle along with an optimized split injection strategy. The results show, in this case, the fuel spray impinges at the edge of the piston bowl and a counterclockwise flow motion is generated that pushes mixture toward the center of the piston bowl.

  2. Performance and combustion characteristics of direct-injection stratified-charge rotary engines

    Science.gov (United States)

    Nguyen, Hung Lee

    1987-01-01

    Computer simulations of the direct-injection stratified-charge (DISC) Wankel engine have been used to calculate heat release rates and performance and efficiency characteristics of the 1007R engine. Engine pressure data have been used in a heat release analysis to study the effects of heat transfer, leakage, and crevice flows. Predicted engine performance data are compared with experimental test data over a range of engine speeds and loads. An examination of methods to improve the performance of the Wankel engine with faster combustion, reduced leakage, higher compression ratio, and turbocharging is presented.

  3. Turbulence-combustion interaction in direct injection diesel engine

    Directory of Open Access Journals (Sweden)

    Bencherif Mohamed

    2014-01-01

    Full Text Available The experimental measures of chemical species and turbulence intensity during the closed part of the engine combustion cycle are today unattainable exactly. This paper deals with numerical investigations of an experimental direct injection Diesel engine and a commercial turbocharged heavy duty direct injection one. Simulations are carried out with the kiva3v2 code using the RNG (k-ε model. A reduced mechanism for n-heptane was adopted for predicting auto-ignition and combustion processes. From the calibrated code based on experimental in-cylinder pressures, the study focuses on the turbulence parameters and combustion species evolution in the attempt to improve understanding of turbulence-chemistry interaction during the engine cycle. The turbulent kinetic energy and its dissipation rate are taken as representative parameters of turbulence. The results indicate that chemistry reactions of fuel oxidation during the auto-ignition delay improve the turbulence levels. The peak position of turbulent kinetic energy coincides systematically with the auto-ignition timing. This position seems to be governed by the viscous effects generated by the high pressure level reached at the auto-ignition timing. The hot regime flame decreases rapidly the turbulence intensity successively by the viscous effects during the fast premixed combustion and heat transfer during other periods. It is showed that instable species such as CO are due to deficiency of local mixture preparation during the strong decrease of turbulence energy. Also, an attempt to build an innovative relationship between self-ignition and maximum turbulence level is proposed. This work justifies the suggestion to determine otherwise the self-ignition timing.

  4. Characteristics of pressure wave in common rail fuel injection system of high-speed direct injection diesel engines

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Herfatmanesh

    2016-05-01

    Full Text Available The latest generation of high-pressure common rail equipment now provides diesel engines possibility to apply as many as eight separate injection pulses within the engine cycle for reducing emissions and for smoothing combustion. With these complicated injection arrangements, optimizations of operating parameters for various driving conditions are considerably difficult, particularly when integrating fuel injection parameters with other operating parameters such as exhaust gas recirculation rate and boost pressure together for evaluating calibration results. Understanding the detailed effects of fuel injection parameters upon combustion characteristics and emission formation is therefore particularly critical. In this article, the results and discussion of experimental investigations on a high-speed direct injection light-duty diesel engine test bed are presented for evaluating and analyzing the effects of main adjustable parameters of the fuel injection system on all regulated emission gases and torque performance. Main injection timing, rail pressure, pilot amount, and particularly pilot timing have been examined. The results show that optimization of each of those adjustable parameters is beneficial for emission reduction and torque improvement under different operating conditions. By exploring the variation in the interval between the pilot injection and the main injection, it is found that the pressure wave in the common rail has a significant influence on the subsequent injection. This suggests that special attentions must be paid for adjusting pilot timing or any injection interval when multi-injection is used. With analyzing the fuel amount oscillation of the subsequent injections to pilot separation, it demonstrates that the frequency of regular oscillations of the actual fuel amount or the injection pulse width with the variation in pilot separation is always the same for a specified fuel injection system, regardless of engine speed

  5. Researches on direct injection in internal-combustion engines

    Science.gov (United States)

    Tuscher, Jean E

    1941-01-01

    These researches present a solution for reducing the fatigue of the Diesel engine by permitting the preservation of its components and, at the same time, raising its specific horsepower to a par with that of carburetor engines, while maintaining for the Diesel engine its perogative of burning heavy fuel under optimum economical conditions. The feeding of Diesel engines by injection pumps actuated by engine compression achieves the required high speeds of injection readily and permits rigorous control of the combustible charge introduced into each cylinder and of the peak pressure in the resultant cycle.

  6. 2D temperature field measurement in a direct-injection engine using LIF technology

    Science.gov (United States)

    Liu, Yongfeng; Tian, Hongsen; Yang, Jianwei; Sun, Jianmin; Zhu, Aihua

    2011-12-01

    A new multi-spectral detection strategy for temperature laser- induced- fluorescence (LIF) 2-D imaging measurements is reported for high pressure flames in high-speed diesel engine. Schematic of the experimental set-up is outlined and the experimental data on the diesel engine is summarized. Experiment injection system is a third generation Bosch high-pressure common rail featuring a maximum pressure of 160MPa. The injector is equipped with a six-hole nozzle, where each hole has a diameter of 0.124 mm. and slightly offset to the center of the cylinder axis to allow a better cooling of the narrow bridge between the exhaust valves. The measurement system includes a blower, which supplied the intake flow rate, and a prototype single-valve direct injection diesel engine head modified to lay down the swirled-type injector. 14-bit digital CCD cameras are employed to achieve a greater level of accuracy in comparison to the results of previous measurements. The temperature field spatial distributions in the cylinder for different crank angle degrees are carried out in a single direct-injection diesel engine.

  7. Numerical investigation of natural gas direct injection properties and mixture formation in a spark ignition engine

    Directory of Open Access Journals (Sweden)

    Yadollahi Bijan

    2014-01-01

    Full Text Available In this study, a numerical model has been developed in AVL FIRE software to perform investigation of Direct Natural Gas Injection into the cylinder of Spark Ignition Internal Combustion Engines. In this regard two main parts have been taken into consideration, aiming to convert an MPFI gasoline engine to direct injection NG engine. In the first part of study multi-dimensional numerical simulation of transient injection process, mixing and flow field have been performed via three different validation cases in order to assure the numerical model validity of results. Adaption of such a modeling was found to be a challenging task because of required computational effort and numerical instabilities. In all cases present results were found to have excellent agreement with experimental and numerical results from literature. In the second part, using the moving mesh capability the validated model has been applied to methane Injection into the cylinder of a Direct Injection engine. Five different piston head shapes along with two injector types have been taken into consideration in investigations. A centrally mounted injector location has been adapted to all cases. The effects of injection parameters, combustion chamber geometry, injector type and engine RPM have been studied on mixing of air-fuel inside cylinder. Based on the results, suitable geometrical configuration for a NG DI Engine has been discussed.

  8. The influence of thermal regime on gasoline direct injection engine performance and emissions

    Science.gov (United States)

    Leahu, C. I.; Tarulescu, S.

    2016-08-01

    This paper presents the experimental research regarding to the effects of a low thermal regime on fuel consumption and pollutant emissions from a gasoline direct injection (GDI) engine. During the experimental researches, the temperature of the coolant and oil used by the engine were modified 4 times (55, 65, 75 and 85 oC), monitoring the effects over the fuel consumption and emissions (CO2, CO and NOx). The variations in temperature of the coolant and oil have been achieved through AVL coolant and oil conditioning unit, integrated in the test bed. The obtained experimental results reveals the poor quality of exhaust gases and increases of fuel consumption for the gasoline direct injection engines that runs outside the optimal ranges for coolant and oil temperatures.

  9. Performance of CO2 enrich CNG in direct injection engine

    Science.gov (United States)

    Firmansyah, W. B.; Ayandotun, E. Z.; Zainal, A.; Aziz, A. R. A.; Heika, M. R.

    2015-12-01

    This paper investigates the potential of utilizing the undeveloped natural gas fields in Malaysia with high carbon dioxide (CO2) content ranging from 28% to 87%. For this experiment, various CO2 proportions by volume were added to pure natural gas as a way of simulating raw natural gas compositions in these fields. The experimental tests were carried out using a 4-stroke single cylinder spark ignition (SI) direct injection (DI) compressed natural gas (CNG) engine. The tests were carried out at 180° and 300° before top dead centre (BTDC) injection timing at 3000 rpm, to establish the effects on the engine performance. The results show that CO2 is suppressing the combustion of CNG while on the other hand CNG combustion is causing CO2 dissociation shown by decreasing CO2 emission with the increase in CO2 content. Results for 180° BTDC injection timing shows higher performance compared to 300° BTDC because of two possible reasons, higher volumetric efficiency and higher stratification level. The results also showed the possibility of increasing the CO2 content by injection strategy.

  10. Exhaust gas concentration of CNG fuelled direct injection engine at MBT timing

    International Nuclear Information System (INIS)

    Hassan, M.K.; Aris, I.; Mahmod, S.; Sidek, R.

    2009-01-01

    Full text: This paper presents an experimental result of exhaust gas concentration of high compression engine fuelled with compressed natural gas (CNG) at maximum brake torque (MBT). The engine uses central direct injection (DI) technique to inject the CNG into the cylinder. The engine geometry bases on gasoline engine with 14:1 compression ratio and called CNGDI engine. The injectors are positioned within a certain degrees of spark plug location. The objective of the experiment is to study the influence and significant of MBT timing in CNGDI engine towards exhaust gases. The experimental tests were carried out using computer-controlled eddy-current dynamometer, which measures the CNGDI engine performance. At MBT region, exhaust gas concentration as such CO, HC, NO x , O 2 and CO 2 , were recorded and analyzed during the test using the Horiba analyzer. A closed loop wide band lambda sensor has been mounted at the exhaust manifold to indicate the oxygen level during the exercise. (author)

  11. Performance of a supercharged direct-injection stratified-charge rotary combustion engine

    Science.gov (United States)

    Bartrand, Timothy A.; Willis, Edward A.

    1990-01-01

    A zero-dimensional thermodynamic performance computer model for direct-injection stratified-charge rotary combustion engines was modified and run for a single rotor supercharged engine. Operating conditions for the computer runs were a single boost pressure and a matrix of speeds, loads and engine materials. A representative engine map is presented showing the predicted range of efficient operation. After discussion of the engine map, a number of engine features are analyzed individually. These features are: heat transfer and the influence insulating materials have on engine performance and exhaust energy; intake manifold pressure oscillations and interactions with the combustion chamber; and performance losses and seal friction. Finally, code running times and convergence data are presented.

  12. Study on the combustion and hydrocarbon emission characteristics of direct injection spark-ignition engines during the direct-start process

    International Nuclear Information System (INIS)

    Shi, Lei; Xiao, Maoyu; Deng, Kangyao

    2015-01-01

    Highlights: • Mixture concentration in first-combustion cylinder of direct start is measured. • Factors that affect direct start performances are investigated. • Combustion characteristics of first-combustion cylinder are analyzed. • Hydrocarbon emission is considered to determined control strategies of direct start. - Abstract: This study was conducted to investigate the combustion and emissions characteristics of the first-combustion cylinder in a direct-start process. The explosive energy of the first combustion is important for the success of a direct start, but this combustion was rarely addressed in recent research. For a 2.0 L direct-injection spark-ignition engine, the in-cylinder mixture concentration, cylinder pressure, engine speed and exhaust hydrocarbon concentration were detected to analyze the fuel evaporation, combustion, engine movement and engine emissions, respectively. In the first-combustion cylinder of the direct-start process, the injected fuel was often enriched to ensure that an appropriate mixture concentration was obtained for ignition without misfiring. Approximately one-third of the injected fuel would not participate in the combustion process and would therefore reduce the exhaust hydrocarbon emissions. The start position determined the amount of the total explosive energy in the first-combustion cylinder, and an optimal start position for a direct start was found to be at a 70–80° crank angle before the top dead center to obtain a better combustion performance and lower emissions. A lower coolant temperature increased the maximum explosion energy of the first combustion, but additional hydrocarbon emissions were generated. Because there was almost no problem in the direct-start capability with different coolant temperatures after an idling stop, it was necessary to maintain the coolant temperature when the engine was stopped

  13. Effects of turbulence enhancement on combustion process using a double injection strategy in direct-injection spark-ignition (DISI) gasoline engines

    International Nuclear Information System (INIS)

    Kim, Taehoon; Song, Jingeun; Park, Sungwook

    2015-01-01

    Highlights: • Using double injection strategy, turbulent kinetic energy can be improved with slight decrease in mixture homogeneity. • Retarded first injection timing reduces vapor fuel loss to intake port. • Double injection increases tumble intensity. • High turbulent intensity caused by double injection increases flame propagation speed. - Abstract: Direct-injection spark-ignition (DISI) gasoline engines have been spotlighted due to their high thermal efficiency. Increase in the compression ratio that result from the heat absorption effect of fuel vaporization induces higher thermal efficiency than found in port fuel injection (PFI) engines. Since fuel is injected at the cylinder directly, various fuel injection strategies can be used. In this study, turbulent intensity was improved by a double injection strategy while maintaining mixture homogeneity. To analyze the turbulence enhancement effects using the double injection strategy, a side fuel injected, homogeneous-charge-type DISI gasoline engine with a multi-hole-type injector was utilized. The spray model was evaluated using experimental data for various injection pressures and the combustion model was evaluated for varied ignition timing. First and second injection timing was swept by 20 degree interval. The turbulent kinetic energy and mixture inhomogeneity index were mapped. First injection at the middle of the intake stroke and second injection early in the compression stroke showed improved turbulent characteristics that did not significantly decrease with mixture homogeneity. A double injection case that showed improved turbulent intensity while maintaining an adequate level of mixture homogeneity and another double injection case that showed significantly improved turbulent intensity with a remarkable decrease in mixture homogeneity were considered for combustion simulation. We found that the improved turbulent intensity increased the flame propagation speed. Also, the mixture homogeneity

  14. Combustion characteristics of a gasoline engine with independent intake port injection and direct injection systems for n-butanol and gasoline

    International Nuclear Information System (INIS)

    He, Bang-Quan; Chen, Xu; Lin, Chang-Lin; Zhao, Hua

    2016-01-01

    Highlights: • Different injection approaches for n-butanol and gasoline affect combustion events. • High n-butanol percentage in the total energy of fuels improves combustion stability. • N-butanol promotes ignition and shortens combustion duration. • Lean burn increases indicated mean effective pressure at fixed total energy of fuels. • Different fuel injection methods slightly affect indicated mean effective pressure. - Abstract: N-butanol, as a sustainable biofuel, is usually used as a blend with gasoline in spark ignition engines. In this study, the combustion characteristics were investigated on a four-cylinder spark ignition gasoline engine with independent port fuel injection and direct injection systems for n-butanol and gasoline in different operating conditions. The results show that in the case of port fuel injection of n-butanol with direct injection gasoline at a given total energy released in a cycle, indicated mean effective pressure is slightly affected by spark timing at stoichiometry while it changes much more with delayed spark timing in lean burn conditions and is much higher in lean burn conditions compared to stoichiometry at given spark timings. With the increase of n-butanol percentage in a fixed total energy released in a cycle at given spark timings, ignition timing advances, combustion duration shortens, indicated mean effective pressure and indicated thermal efficiency increase. For the cases of port fuel injection of n-butanol with direction injection gasoline and port fuel injection of gasoline with direction injection n-butanol at a fixed total energy released in a cycle, their indicated mean effective pressures are close. But their combustion processes are dependent on fuel injection approaches.

  15. Modeling analysis of urea direct injection on the NOx emission reduction of biodiesel fueled diesel engines

    International Nuclear Information System (INIS)

    An, H.; Yang, W.M.; Li, J.; Zhou, D.Z.

    2015-01-01

    Highlights: • The effects of urea direct injection on NO x emissions reduction was investigated. • Aqueous urea solution was proposed to be injected after the fuel injection process. • The optimized injection strategy achieved a reduction efficiency of 58%. • There were no severe impacts on the CO emissions and BSFC. - Abstract: In this paper, a numerical simulation study was conducted to explore the possibility of an alternative approach: direct aqueous urea solution injection on the reduction of NO x emissions of a biodiesel fueled diesel engine. Simulation studies were performed using the 3D CFD simulation software KIVA4 coupled with CHEMKIN II code for pure biodiesel combustion under realistic engine operating conditions of 2400 rpm and 100% load. The chemical behaviors of the NO x formation and urea/NO x interaction processes were modeled by a modified extended Zeldovich mechanism and urea/NO interaction sub-mechanism. To ensure an efficient NO x reduction process, various aqueous urea injection strategies in terms of post injection timing, injection angle, and injection rate and urea mass fraction were carefully examined. The simulation results revealed that among all the four post injection timings (10 °ATDC, 15 °ATDC, 20 °ATDC and 25 °ATDC) that were evaluated, 15 °ATDC post injection timing consistently demonstrated a lower NO emission level. The orientation of the aqueous urea injection was also shown to play a critical role in determining the NO x removal efficiency, and 50 degrees injection angle was determined to be the optimal injection orientation which gave the most NO x reduction. In addition, both the urea/water ratio and aqueous urea injection rate demonstrated important roles which affected the thermal decomposition of urea into ammonia and the subsequent NO x removal process, and it was suggested that 50% urea mass fraction and 40% injection rate presented the lowest NO emission levels. At last, with the optimized injection

  16. Prediction and Validation of Heat Release Direct Injection Diesel Engine Using Multi-Zone Model

    Science.gov (United States)

    Anang Nugroho, Bagus; Sugiarto, Bambang; Prawoto; Shalahuddin, Lukman

    2014-04-01

    The objective of this study is to develop simulation model which capable to predict heat release of diesel combustion accurately in efficient computation time. A multi-zone packet model has been applied to solve the combustion phenomena inside diesel cylinder. The model formulations are presented first and then the numerical results are validated on a single cylinder direct injection diesel engine at various engine speed and timing injections. The model were found to be promising to fulfill the objective above.

  17. Numerical investigation of CAI Combustion in the Opposed- Piston Engine with Direct and Indirect Water Injection

    Science.gov (United States)

    Pyszczek, R.; Mazuro, P.; Teodorczyk, A.

    2016-09-01

    This paper is focused on the CAI combustion control in a turbocharged 2-stroke Opposed-Piston (OP) engine. The barrel type OP engine arrangement is of particular interest for the authors because of its robust design, high mechanical efficiency and relatively easy incorporation of a Variable Compression Ratio (VCR). The other advantage of such design is that combustion chamber is formed between two moving pistons - there is no additional cylinder head to be cooled which directly results in an increased thermal efficiency. Furthermore, engine operation in a Controlled Auto-Ignition (CAI) mode at high compression ratios (CR) raises a possibility of reaching even higher efficiencies and very low emissions. In order to control CAI combustion such measures as VCR and water injection were considered for indirect ignition timing control. Numerical simulations of the scavenging and combustion processes were performed with the 3D CFD multipurpose AVL Fire solver. Numerous cases were calculated with different engine compression ratios and different amounts of directly and indirectly injected water. The influence of the VCR and water injection on the ignition timing and engine performance was determined and their application in the real engine was discussed.

  18. Laser-induced breakdown spectroscopy for lambda quantification in a direct-injection engine

    International Nuclear Information System (INIS)

    Buschbeck, M.; Büchler, F.; Halfmann, T.; Arndt, S.

    2012-01-01

    We apply laser-induced breakdown spectroscopy (LIBS) to determine local lambda values (i.e. the normalized air-fuel mass ratio) at the ignition location λ ip in a direct-injection single-cylinder optical research engine. The technique enables us to determine variations of λ ip for different fuel injection strategies, as well as correlations between variations in λ ip and the combustion dynamics. In particular we observe, that fluctuations in λ ip are not the major cause of cycle-to-cycle variations in the combustion process. Moreover, our experiments identify insufficient lean λ ip values as a source of misfires in lean combustions. In a combination of LIBS with laser-induced fluorescence (LIF), we obtain additionally information about the two-dimensional λ distribution. These results demonstrate the potential of LIBS to monitor λ values during mixture formation in gasoline engines. - Highlights: ► Determination of λ values by means of LIBS in an optical gasoline engine. ► Evaluation of λ fluctuations for different fuel injection strategies. ► Investigation of the effect of λ upon combustion dynamics. ► Combination of LIBS and LIF to obtain two-dimensional λ distributions.

  19. Soot and smoke emissions numerical evaluation for a direct injection (DI diesel engine

    Directory of Open Access Journals (Sweden)

    Radu Bogdan

    2017-01-01

    Full Text Available The reduction of Diesel internal combustion engines emissions is one of the major concerns of the engines manufacturers. Despite the fact that the efficiency of the gas post-treatment systems has been significantly improved, decreasing the smoke and the soot from the cylinder inside remains a main research goal. This work is proposing a theoretical study on these pollutants formation for different kinds of direct injection methods. By dividing the in-cylinder injection the heat release characteristic could be modified, leading to different temperature and pressure levels. Using exhaust gas recirculation (EGR the reduction of the gas temperatures might also be decreased, limiting NOx formation. To evaluate the level of the cylinder gas emissions formation a two-step procedure could be followed. First, by using a numerical calculation system the heat release characteristic can be highlighted concerning a Diesel engine with stratified injection; then, using an experimental relationship applying a large data base, the amount of the gas emissions can be subsequently provided. The authors propose some combinations between injection characteristics and EGR used fractions which could generate successfully results speaking in terms of NOx, soot and smoke formation.

  20. Effect of the Ethanol Injection Moment During Compression Stroke on the Combustion of Ethanol - Diesel Dual Direct Injection Engine

    Science.gov (United States)

    Liang, Yu; Zhou, Liying; Huang, Haomin; Xu, Mingfei; Guo, Mei; Chen, Xin

    2018-01-01

    A set of GDI system is installed on a F188 single-cylinder, air-cooled and direct injection diesel engine, which is used for ethanol injection, with the injection time controlled by the crank angle signal collected by AVL angle encoder. The injection of ethanol amounts to half of the thermal equivalent of an original diesel fuel. A 3D combustion model is established for the ethanol - diesel dual direct injection engine. Diesel was injected from the original fuel injection system, with a fuel supply advance angle of 20°CA. The ethanol was injected into the cylinder during compression process. Diesel injection began after the completion of ethanol injection. Ethanol injection starting point of 240°CA, 260°CA, 280°CA, 300°CA and 319.4°CA were simulated and analyzed. Due to the different timing of ethanol injection, the ignition of the ethanol mixture when diesel fires, results in non-uniform ignition distribution and flame propagation rate, since the distribution and concentration gradients of the ethanol mixture in the cylinder are different, thus affecting the combustion process. The results show that, when ethanol is injected at 319.4°CA, the combustion heat release rate and the pressure rise rate during the initial stage are the highest. Also, the maximum combustion pressure, with a relatively advance phase, is the highest. In case of later initial ethanol injection, the average temperature in the cylinder during the initial combustion period will have a faster rise. In case of initial injection at 319.4°CA, the average temperature in the cylinder is the highest, followed by 240°CA ethanol injection. In the post-combustion stage, the earlier ethanol injection will result in higher average temperature in the cylinder and more complete fuel combustion. The injection of ethanol at 319.4°CA produces earlier and highest NOX emissions.

  1. Asymptotic analysis soot model and experiment for a directed injection engine

    Science.gov (United States)

    Liu, Yongfeng; Pei, Pucheng; Xiong, Qinghui; Lu, Yong

    2012-09-01

    The existing soot models are either too complex and can not be applied to the internal combustion engine, or too simple to make calculation errors. Exploring the soot model becomes the pursuit of the goal of many researchers within the error range in the current computer speed. On the basis of the latest experimental results, TP (temperature phases) model is presented as a new soot model to carry out optimization calculation for a high-pressure common rail diesel engine. Temperature and excess air factor are the most important two parameters in this model. When zone temperature T0.6, only the soot precursors—polycyclic aromatic hydrocarbons(PAH) is created and there is no soot emission. When zone temperature T ⩾ 1 500 K and excess air factor Φinjection time, variation of rail pressure and variation of speed among TP models. The experimental results indicate that the TP model can carry out optimization and computational fluid dynamics can be a tool to calculate for a high-pressure common rail directed injection diesel engine. The TP model result is closer than the use of the original KIVA-3V results of soot model accuracy by about 50% and TP model gives a new method for engine researchers.

  2. Direct-injection strategies for a hydrogen-fueled engine : an optical and numerical investigation

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser, S.; Salazar, V. [Sandia National Labs, Albuquerque, NM (United States); Scarcelli, R.; Wallner, T. [Argonne National Lab, Argonne, IL (United States)

    2009-07-01

    Vehicles with hydrogen-fueled engines are competitive with systems based on fuel cells. There is a lack of fundamental knowledge about in-cylinder processes in hydrogen direct injection engines. This presentation discussed a study that used a variety of injector configurations to establish a broad database. A light-load conditions that can profit from stratification was investigated. Several results were presented, including the 5-hole nozzle produced an asymmetric jet pattern which may be good for late injection. Very lean regions in the wake of the transient jets were found to be similar to those found in diesel injection. The 13-hole nozzle demonstrated complete jet collapse, consistent with Schlieren imaging by Petersen. Stratification made efficiency sensitive to the targeting of the single-hole injector. Computational fluid dynamics with a commercially available code aimed to improve the process of design optimization. The simulation predicted less fuel dispersion than was experimentally measured. Details of the fuel penetration were captured. It was concluded that for the single-hole nozzle, the pre-spark fuel distribution is consistent with results from the fired engine. tabs., figs.

  3. Towards 40% efficiency with BMEP exceeding 30 bar in directly injected, turbocharged, spark ignition ethanol engines

    International Nuclear Information System (INIS)

    Boretti, Alberto

    2012-01-01

    Highlights: ► The main advantages of ethanol vs. gasoline are higher knock resistance and heat of vaporization. ► Direct injection and turbo charging are the key features of high efficiency and high power density ethanol engines. ► Advanced ethanol engines are enablers of vehicle fuel energy economy similar to Diesel engines. ► Waste bio mass ethanol may cut the nonrenewable energy costs of fossil fuels passenger cars by almost 90%. - Abstract: Current flexi fuel gasoline and ethanol engines have efficiencies generally lower than dedicated gasoline engines. Considering ethanol has a few advantages with reference to gasoline, namely the higher octane number and the larger heat of vaporization, the paper explores the potentials of dedicated pure ethanol engines using the most advanced techniques available for gasoline engines, specifically direct injection, turbo charging and variable valve actuation. Computations are performed with state-of-the-art, well validated, engine and vehicle performance simulations packages, generally accepted to produce accurate results when targeting major trends in engine developments. The higher compression ratio and the higher boost permitted by ethanol allows larger than gasoline top engine brake thermal efficiencies and peak power and torque, while the variable valve actuation produces smaller penalties in efficiency changing the load than in conventional throttle controlled engines.

  4. Experimental investigation of the effects of direct water injection parameters on engine performance in a six-stroke engine

    International Nuclear Information System (INIS)

    Arabaci, Emre; İçingür, Yakup; Solmaz, Hamit; Uyumaz, Ahmet; Yilmaz, Emre

    2015-01-01

    Highlights: • Exhaust gas temperature and specific fuel consumption decreased with six stroke engine. • Thermal efficiency increased with water injection. • NO emissions decreased with water injection as the temperature decreased at the end of cycle. • Injection timing should be advanced with the increase of engine speed. • HC and CO emissions decrease until 3000 rpm engine speed. - Abstract: In this study, the effects of water injection quantity and injection timing were investigated on engine performance and exhaust emissions in a six-stroke engine. For this purpose, a single cylinder, four-stroke gasoline engine was converted to six-stroke engine modifying a new cam mechanism and adapting the water injection system. The experiments were conducted at stoichometric air/fuel ratio (λ = 1) between 2250 and 3500 rpm engine speed at full load with liquid petroleum gas. Water injection was performed at three different stages as before top dead center, top dead center and after top dead center at constant injection duration and four different injection pressure 25, 50, 75 and 100 bar. The test results showed that exhaust gas temperature and specific fuel consumption decreased by about 7% and 9% respectively. In contrast, fuel consumption and power output increased 2% and 10% respectively with water injection. Thermal efficiency increased by about 8.72% with water injection. CO and HC emissions decreased 21.97% and 18.23% until 3000 rpm respectively. NO emissions decreased with water injection as the temperature decreased at the end of cycle. As a result, it was seen that engine performance improved when suitable injection timing and injected water quantity were selected due to effect of exhaust heat recovery with water injection

  5. Ducted combustion chamber for direct injection engines and method

    Science.gov (United States)

    Mueller, Charles

    2015-03-03

    An internal combustion engine includes an engine block having a cylinder bore and a cylinder head having a flame deck surface disposed at one end of the cylinder bore. A piston connected to a rotatable crankshaft and configured to reciprocate within the cylinder bore has a piston crown portion facing the flame deck surface such that a combustion chamber is defined within the cylinder bore and between the piston crown and the flame deck surface. A fuel injector having a nozzle tip disposed in fluid communication with the combustion chamber has at least one nozzle opening configured to inject a fuel jet into the combustion chamber along a fuel jet centerline. At least one duct defined in the combustion chamber between the piston crown and the flame deck surface has a generally rectangular cross section and extends in a radial direction relative to the cylinder bore substantially along the fuel jet centerline.

  6. Performance of single cylinder, direct injection Diesel engine using water fuel emulsions

    International Nuclear Information System (INIS)

    Abu-Zaid, M.

    2004-01-01

    A single cylinder Diesel engine study of water-in-Diesel emulsions was conducted to investigate the effect of water emulsification on the engine performance and gases exhaust temperature. Emulsified Diesel fuels of 0, 5, 10, 15 and 20 water/Diesel ratios by volume, were used in a single cylinder, direct injection Diesel engine, operating at 1200-3300 rpm. The results indicate that the addition of water in the form of emulsion improves combustion efficiency. The engine torque, power and brake thermal efficiency increase as the water percentage in the emulsion increases. The average increase in the brake thermal efficiency for 20% water emulsion is approximately 3.5% over the use of Diesel for the engine speed range studied. The proper brake specific fuel consumption and gases exhaust temperature decrease as the percentage of water in the emulsion increases

  7. Super Turbocharging the Direct Injection Diesel engine

    Science.gov (United States)

    Boretti, Albert

    2018-03-01

    The steady operation of a turbocharged diesel direct injection (TDI) engine featuring a variable speed ratio mechanism linking the turbocharger shaft to the crankshaft is modelled in the present study. Key parameters of the variable speed ratio mechanism are range of speed ratios, efficiency and inertia, in addition to the ability to control relative speed and flow of power. The device receives energy from, or delivers energy to, the crankshaft or the turbocharger. In addition to the pistons of the internal combustion engine (ICE), also the turbocharger thus contributes to the total mechanical power output of the engine. The energy supply from the crankshaft is mostly needed during sharp accelerations to avoid turbo-lag, and to boost torque at low speeds. At low speeds, the maximum torque is drastically improved, radically expanding the load range. Additionally, moving closer to the points of operation of a balanced turbocharger, it is also possible to improve both the efficiency η, defined as the ratio of the piston crankshaft power to the fuel flow power, and the total efficiency η*, defined as the ratio of piston crankshaft power augmented of the power from the turbocharger shaft to the fuel flow power, even if of a minimal extent. The energy supply to the crankshaft is possible mostly at high speeds and high loads, where otherwise the turbine could have been waste gated, and during decelerations. The use of the energy at the turbine otherwise waste gated translates in improvements of the total fuel conversion efficiency η* more than the efficiency η. Much smaller improvements are obtained for the maximum torque, yet again moving closer to the points of operation of a balanced turbocharger. Adopting a much larger turbocharger (target displacement x speed 30% larger than a conventional turbocharger), better torque outputs and fuel conversion efficiencies η* and η are possible at every speed vs. the engine with a smaller, balanced turbocharger. This result

  8. Baseline performance and emissions data for a single-cylinder, direct-injected diesel engine

    Science.gov (United States)

    Dezelick, R. A.; Mcfadden, J. J.; Ream, L. W.; Barrows, R. F.

    1983-01-01

    Comprehensive fuel consumption, mean effective cylinder pressure, and emission test results for a supercharged, single-cylinder, direct-injected, four-stroke-cycle, diesel test engine are documented. Inlet air-to-exhaust pressure ratios were varied from 1.25 to 3.35 in order to establish the potential effects of turbocharging techniques on engine performance. Inlet air temperatures and pressures were adjusted from 34 to 107 C and from 193 to 414 kPa to determine the effects on engine performance and emissions. Engine output ranged from 300 to 2100 kPa (brake mean effective pressure) in the speed range of 1000 to 3000 rpm. Gaseous and particulate emission rates were measured. Real-time values of engine friction and pumping loop losses were measured independently and compared with motored engine values.

  9. Rotary engine developments at Curtiss-Wright over the past 20 years and review of general aviation engine potential. [with direct chamber injection

    Science.gov (United States)

    Jones, C.

    1978-01-01

    The development of the rotary engine as a viable power plant capable of wide application is reviewed. Research results on the stratified charge engine with direct chamber injection are included. Emission control, reduced fuel consumption, and low noise level are among the factors discussed in terms of using the rotary engine in general aviation aircraft.

  10. The Effect of Ethanol-Diesel Blends on The Performance of A Direct Injection Diesel Engine

    OpenAIRE

    Arifin Nur; Yanuandri Putrasari; Iman Kartolaksono Reksowardojo

    2012-01-01

    The experiment was conducted on a conventional direct injection diesel engine. Performance test was carried out to evaluate the performance and emission characteristics of a conventional diesel engine that operates on ethanol-diesel blends. The test procedure was performed by coupling the diesel engine on the eddy current dynamometer. Fuel consumption was measured using the AVL Fuel Balance, and a hotwire anemometer was used to measure the air consumption. Some of the emission test devices we...

  11. Analysis of mixture formation of direct injection gasoline engine; Tonai funsha gasoline engine no kongoki keisei kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Kano, M; Saito, K; Basaki, M [Nippon Soken, Inc., Tokyo (Japan); Matsushita, S; Gono, T [Toyota Motor Corp., Aichi (Japan)

    1997-10-01

    On direct injection gasoline engine, in order to achieve good stratified combustion, the extremely advanced control of air-fuel mixture is required. For this purpose, the method of diagnosing the quality of the state of mixture formation in combustion chambers becomes necessary. In this research, the state of air-fuel mixture in the combustion chamber of a TOYOTA D-4 was analyzed in space and time by visualization, A/F multi-point measurement and A/F high response measurement, thus the effects that injection timing, swirl and fuel pressure exerted to mixture formation were elucidated. 3 refs., 17 figs., 1 tab.

  12. About the constructive and functional particularities of spark ignition engines with gasoline direct injection: experimental results

    Science.gov (United States)

    Niculae, M.; Ivan, F.; Neacsu, D.

    2017-08-01

    The paper aims to analyze and compare the environmental performances between a gasoline direct engine and a multi-point injection engine. There are analyzed the stages of emission formation during the New European Driving Cycle. The paper points out the dynamic, economic and environmental performances of spark ignition engines equipped with a GDI systems. Reason why, we believe the widespread implementation of this technology is today an immediate need.

  13. Hydrogen Gas as a Fuel in Direct Injection Diesel Engine

    Science.gov (United States)

    Dhanasekaran, Chinnathambi; Mohankumar, Gabriael

    2016-04-01

    Hydrogen is expected to be one of the most important fuels in the near future for solving the problem caused by the greenhouse gases, for protecting environment and saving conventional fuels. In this study, a dual fuel engine of hydrogen and diesel was investigated. Hydrogen was conceded through the intake port, and simultaneously air and diesel was pervaded into the cylinder. Using electronic gas injector and electronic control unit, the injection timing and duration varied. In this investigation, a single cylinder, KIRLOSKAR AV1, DI Diesel engine was used. Hydrogen injection timing was fixed at TDC and injection duration was timed for 30°, 60°, and 90° crank angles. The injection timing of diesel was fixed at 23° BTDC. When hydrogen is mixed with inlet air, emanation of HC, CO and CO2 decreased without any emission (exhaustion) of smoke while increasing the brake thermal efficiency.

  14. Factors affecting the development of sprays produced by multihole injectors for direct-injection engine applications

    OpenAIRE

    Van Romunde, R. Z.

    2011-01-01

    The spray form development from a state of the art multi-hole injector for gasoline direct injection internal combustion engines is examined to attempt to determine the thermo-fluid dynamics affecting the spray development. The current state of knowledge regarding spray break-up and the interactivity of the factors on spray form are detailed. The spray under investigation was injected into purposely designed quiescent chambers to decouple the effects of the fluid mechanics on s...

  15. Performance and efficiency evaluation and heat release study of a direct-injection stratified-charge rotary engine

    Science.gov (United States)

    Nguyen, H. L.; Addy, H. E.; Bond, T. H.; Lee, C. M.; Chun, K. S.

    1987-01-01

    A computer simulation which models engine performance of the Direct Injection Stratified Charge (DISC) rotary engines was used to study the effect of variations in engine design and operating parameters on engine performance and efficiency of an Outboard Marine Corporation (OMC) experimental rotary combustion engine. Engine pressure data were used in a heat release analysis to study the effects of heat transfer, leakage, and crevice flows. Predicted engine data were compared with experimental test data over a range of engine speeds and loads. An examination of methods to improve the performance of the rotary engine using advanced heat engine concepts such as faster combustion, reduced leakage, and turbocharging is also presented.

  16. Influence of Injector Location on Part-Load Performance Characteristics of Natural Gas Direct-Injection in a Spark Ignition Engine

    Energy Technology Data Exchange (ETDEWEB)

    Sevik, James [Argonne National Lab. (ANL), Argonne, IL (United States); Pamminger, Michael [Argonne National Lab. (ANL), Argonne, IL (United States); Wallner, Thomas [Argonne National Lab. (ANL), Argonne, IL (United States); Scarcelli, Riccardo [Argonne National Lab. (ANL), Argonne, IL (United States); Boyer, Brad [Ford Motor Co., Detroit, MI (United States); Wooldridge, Steven [Ford Motor Co., Detroit, MI (United States); Hall, Carrie [Illinois Inst. of Technology, Chicago, IL (United States); Miers, Scott [Michigan Technological Univ., Houghton, MI (United States)

    2016-04-05

    Interest in natural gas as an alternative fuel source to petroleum fuels for light-duty vehicle applications has increased due to its domestic availability and stable price compared to gasoline. With its higher hydrogen-to-carbon ratio, natural gas has the potential to reduce engine out carbon dioxide emissions, which has shown to be a strong greenhouse gas contributor. For part-load conditions, the lower flame speeds of natural gas can lead to an increased duration in the inflammation process with traditional port-injection. Direct-injection of natural gas can increase in-cylinder turbulence and has the potential to reduce problems typically associated with port-injection of natural gas, such as lower flame speeds and poor dilution tolerance. A study was designed and executed to investigate the effects of direct-injection of natural gas at part-load conditions. Steady-state tests were performed on a single-cylinder research engine representative of current gasoline direct-injection engines. Tests were performed with direct-injection in the central and side location. The start of injection was varied under stoichiometric conditions in order to study the effects on the mixture formation process. In addition, exhaust gas recirculation was introduced at select conditions in order to investigate the dilution tolerance. Relevant combustion metrics were then analyzed for each scenario. Experimental results suggest that regardless of the injector location, varying the start of injection has a strong impact on the mixture formation process. Delaying the start of injection from 300 to 120°CA BTDC can reduce the early flame development process by nearly 15°CA. While injecting into the cylinder after the intake valves have closed has shown to produce the fastest combustion process, this does not necessarily lead to the highest efficiency, due to increases in pumping and wall heat losses. When comparing the two injection configurations, the side location shows the best

  17. Exploring the limits of a down-sized ethanol direct injection spark ignited engine in different configurations in order to replace high-displacement gasoline engines

    International Nuclear Information System (INIS)

    Baêta, José Guilherme Coelho; Pontoppidan, Michael; Silva, Thiago R.V.

    2015-01-01

    Highlights: • The limits of a highly boosted down-sized ethanol engine was investigated. • 28% of fuel consumption reduction was achieved by means of an extreme down-sizing. • 53% of down-sizing was reached by means of cutting-edge technologies implementation. • Engine efficiency at partial load was also investigated. • A significant decrease in engine-out emissions was achieved. - Abstract: The paper presents a layout of a highly boosted Ethanol Direct Injected engine in order to explore the limits of down-sizing for replacing high-displacement gasoline engines, which represents a powerful means of reducing fuel consumption and engine-out emissions at reduced production costs. The substitution of high-displacement engines (2.4- or 3.0-l) by a down-sized turbocharged Ethanol Direct Injected engine is studied. This document describes the detailed layout of all engine hardware and in particular, the cylinder head structure including the optimized intake and exhaust manifolds as well as implemented direct injection injectors. The work continues with a presentation of the experimental data obtained at the engine test rig. A series of experimental data is also presented for the down-sized engine mounted in a car as a replacement for its original high-displacement engine. Substantial fuel consumption gains are obtained as well as values of engine torque for the down-sized, down-speeded prototype engine, which makes it possible to replace engines with much higher displacements. As a result the maximum obtained efficiency of the 1.4 l prototype engine with twin-stage compressor reaches a value of 3250 kPa brake pressure at 44% efficiency. The present work is a very new and different approach compared to previous published studies on ethanol and down-sized engines due to the fact that the Brazilian hydrated ethanol fuel (7% water content) has a major charge effect compared to North American and European Gasoline and alcohol fuels (consult Table 1). This means that

  18. Study of nozzle deposit formation mechanism for direct injection gasoline engines; Chokufun gasoline engine yo nozzle no deposit seisei kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Kinoshita, M; Saito, A [Toyota Central Research and Development Labs., Inc., Aichi (Japan); Matsushita, S [Toyota Motor Corp., Aichi (Japan); Shibata, H [Nippon Soken, Inc., Tokyo (Japan); Niwa, Y [Denso Corp., Aichi (Japan)

    1997-10-01

    Nozzles in fuel injectors for direct injection gasoline engines are exposed to high temperature combustion gases and soot. In such a rigorous environment, it is a fear that fuel flow rate changes in injectors by deposit formation on nozzles. Fundamental factors of nozzle deposit formation were investigated through injector bench tests and engine dynamometer tests. Deposit formation processes were observed by SEM through engine dynamometer tests. The investigation results reveal nozzle deposit formation mechanism and how to suppress the deposit. 4 refs., 8 figs., 3 tabs.

  19. Test results of pongamia pinnata methyl esters with direct injection diesel engine

    International Nuclear Information System (INIS)

    Bannikov, MG.; Chattha, J.A.; Khan, A.F.

    2011-01-01

    Pongamia Pinnata oil is considered as a potential source of biodiesel production in Pakistan. When selecting source for commercial production of biodiesel several criteria are used. One of them is that biodiesel or biodiesel/diesel fuel blends must provide satisfactory performance and emissions of the diesel engine without or with a little engine modification. In this research performance and emissions characteristics of a direct injection diesel engine running on Pongamia Pinnata methyl esters were discussed. Discussion was supported by an analysis of combustion characteristics derived from in-cylinder pressure data. Engine running on a neat biodiesel showed higher brake specific fuel consumption and lower brake fuel conversion efficiency at all loads, whereas emissions were improved except of carbon monoxide emission at high loads. Decrease in brake efficiency and reduction of nitrogen oxides emissions were attributed solely to the change in the rate of heat release. Deposits on fuel infector nozzle were observed when engine was running on the neat biodiesel. Based on test results conclusion was made that Pongamia biodiesel/diesel fuel blends can effectively be used as a diesel oil substitute. (author)

  20. Analyse de la sensibilité aux paramètres gazoles d'un moteur diesel d'automobile à injection directe Small Direct Injection Diesel Engine Sensitivity to the Diesel Fuel Characteristics

    Directory of Open Access Journals (Sweden)

    Montagne X.

    2006-12-01

    particules totales sont plutôt dépendantes de la viscosité et des fractions légères des carburants. Les émissions sonores sont étroitement liées à l'indice de cétane. Par ailleurs, l'ensemble des résultats acquis semble indiquer que les paramètres pilotant le délai d'auto-inflammation sont importants sur ce type de convertisseur. Il serait cependant nécessaire de disposer de mesures directes des caractéristiques des jets d'injection (taille des gouttelettes, pénétration du spray en fonction des différents carburants pour pouvoir quantifier l'effet des paramètres tels que la viscosité et la densité sur la partie physique du délai d'auto-inflammation. Among the technical solutions that can lead to energy converters with low pollutant emissions and low fuel consumption, diesel engines rank, by nature, in a good position. On this base, direct injection diesel engine has been developed and are now spreading in private passanger cars because of their performances, especially in terms of fuel consumption. However, this equipment requires an efficient injection system, electronically driven, needs EGR and an oxidation catalyst to improve the pollutant emissions and the noise level. Thus, it is a major concern to be able to assess precisely the sensitivity to fuel characteristics of direct injection engines as to take the best advantage of this technology. With a set of fuels formulated to cover a large range of chemical nature, viscosity, cetane number and density, an Audi direct injection engine (1Z model was run at the test bench. The impact of the fuel characteristics on pollutant emissions, regulated or unregulated (PAH, aldehydes, and on noise levels was assessed either under standard tuning conditions, either by changing the EGR rate and the injection timing. The results obtained at the end of this program point out the main criteria that have an influence on emissions. They also allow a comparison between direct injection engines and their homologues

  1. Estimation of instantaneous heat transfer coefficients for a direct-injection stratified-charge rotary engine

    Science.gov (United States)

    Lee, C. M.; Addy, H. E.; Bond, T. H.; Chun, K. S.; Lu, C. Y.

    1987-01-01

    The main objective of this report was to derive equations to estimate heat transfer coefficients in both the combustion chamber and coolant pasage of a rotary engine. This was accomplished by making detailed temperature and pressure measurements in a direct-injection stratified-charge rotary engine under a range of conditions. For each sppecific measurement point, the local physical properties of the fluids were calculated. Then an empirical correlation of the coefficients was derived by using a multiple regression program. This correlation expresses the Nusselt number as a function of the Prandtl number and Reynolds number.

  2. Possibilities of Simultaneous In-Cylinder Reduction of Soot and NOx Emissions for Diesel Engines with Direct Injection

    OpenAIRE

    Wagner, U.; Eckert, P.; Spicher, U.

    2008-01-01

    Up to now, diesel engines with direct fuel injection are the propulsion systems with the highest efficiency for mobile applications. Future targets in reducing CO2 -emissions with regard to global warming effects can be met with the help of these engines. A major disadvantage of diesel engines is the high soot and nitrogen oxide emissions which cannot be reduced completely with only engine measures today. The present paper describes two different possibilities for the sim...

  3. Dual-fuelling of a direct-injection automotive diesel engine by diesel and compressed natural gas

    International Nuclear Information System (INIS)

    Pirouzpanah, V.; Mohammadi Kosha, A.; Mosseibi, A.; Moshirabadi, J.; Gangi, A.; Moghadaspour, M.

    2000-01-01

    Application of Compressed Natural Gas in diesel engines has always been important, especially in the field of automotive engineering. This is due to easy accessibility, better mixing quality and good combustion characteristics of the Compressed Natural Gas fuel. In this study the application of Compressed Natural Gas fuel along with diesel oil in a heavy duty direct-injection automotive diesel engine is experimentally investigated. In order to convert a diesel engine into a diesel-gas one, the so called m ixed diesel-gas a pproach has been used and for this purpose a carbureted Compressed Natural Gas fuel system has been designed and manufactured. For controlling quantity of Compressed Natural Gas, the gas valve is linked to the diesel fuel injection system by means of a set of rods. Then, the dual-fuel system is adjusted so that, at full load conditions, the quantity of diesel fuel is reduced to 20% and 80% of its equivalent energy is substituted by Compressed Natural Gas fuel. Also injection pressure of pilot jet is increased by 11.4%. Performance and emission tests are conducted under variation of load and speed on both diesel and diesel-gas engines. Results show that, with equal power and torque, the diesel-gas engine has the potential to improve overall engine performance and emission. For example, at rated power and speed, fuel economy increases by 5.48%, the amount of smoke decreases by 78%, amount of CO decreases by 64.3% and mean exhaust gas temperature decreases by 6.4%

  4. About methods to reduce emissions of turbo charged engine gasoline direct injection

    Science.gov (United States)

    Neacsu, D.; Ivan, F.; Niculae, M.

    2017-08-01

    The paper aims to analyse and explain new methods applied on gasoline direct injection to reduce gas emissions and greenhouse effect. There are analysed the composition of emission inside the engine and which are the most harmful emission for the environment. Will be analysed the methods and systems which have a contribution to decrease emissions produced by the mixture of air and fuel. The paper contains details about after treatment systems which are designed to decrease gas emissions without any other negative consequence on the environment.

  5. Effect of fumigation methanol and ethanol on the gaseous and particulate emissions of a direct-injection diesel engine

    Science.gov (United States)

    Zhang, Z. H.; Tsang, K. S.; Cheung, C. S.; Chan, T. L.; Yao, C. D.

    2011-02-01

    Experiments were conducted on a four-cylinder direct-injection diesel engine with methanol or ethanol injected into the air intake of each cylinder, to compare their effect on the engine performance, gaseous emissions and particulate emissions of the engine under five engine loads at the maximum torque speed of 1800 rev/min. The methanol or ethanol was injected to top up 10% and 20% of the engine loads under different engine operating conditions. The experimental results show that both fumigation methanol and fumigation ethanol decrease the brake thermal efficiency (BTE) at low engine load but improves it at high engine load; however the fumigation methanol has higher influence on the BTE. Compared with Euro V diesel fuel, fumigation methanol or ethanol could lead to reduction of both NOx and particulate mass and number emissions of the diesel engine, with fumigation methanol being more effective than fumigation ethanol in particulate reduction. The NOx and particulate reduction is more effective with increasing level of fumigation. However, in general, fumigation fuels increase the HC, CO and NO 2 emissions, with fumigation methanol leading to higher increase of these pollutants. Compared with ethanol, the fumigation methanol has stronger influence on the in-cylinder gas temperature, the air/fuel ratio, the combustion processes and hence the emissions of the engine.

  6. Injectable biomaterials for adipose tissue engineering

    International Nuclear Information System (INIS)

    Young, D A; Christman, K L

    2012-01-01

    Adipose tissue engineering has recently gained significant attention from materials scientists as a result of the exponential growth of soft tissue filler procedures being performed within the clinic. While several injectable materials are currently being marketed for filling subcutaneous voids, they often face limited longevity due to rapid resorption. Their inability to encourage natural adipose formation or ingrowth necessitates repeated injections for a prolonged effect and thus classifies them as temporary fillers. As a result, a significant need for injectable materials that not only act as fillers but also promote in vivo adipogenesis is beginning to be realized. This paper will discuss the advantages and disadvantages of commercially available soft tissue fillers. It will then summarize the current state of research using injectable synthetic materials, biopolymers and extracellular matrix-derived materials for adipose tissue engineering. Furthermore, the successful attributes observed across each of these materials will be outlined along with a discussion of the current difficulties and future directions for adipose tissue engineering. (paper)

  7. A study of a direct-injection stratified-charge rotary engine for motor vehicle application

    Science.gov (United States)

    Kagawa, Ryoji; Okazaki, Syunki; Somyo, Nobuhiro; Akagi, Yuji

    1993-03-01

    A study of a direct-injection stratified-charge system (DISC), as applied to a rotary engine (RE) for motor vehicle usage, was undertaken. The goals of this study were improved fuel consumption and reduced exhaust emissions. These goals were thought feasible due to the high thermal efficiency associated with the DISC-RE. This was the first application of this technology to a motor vehicle engine. Stable ignition and ideal stratification systems were developed by means of numerical calculations, air-fuel mixture measurements, and actual engine tests. The use of DISC resulted in significantly improved fuel consumption and reduced exhaust emissions. The use of an exhaust gas recirculating system was studied and found to be beneficial in NOx reduction.

  8. The effect of insulated combustion chamber surfaces on direct-injected diesel engine performance, emissions, and combustion

    Science.gov (United States)

    Dickey, Daniel W.; Vinyard, Shannon; Keribar, Rifat

    1988-01-01

    The combustion chamber of a single-cylinder, direct-injected diesel engine was insulated with ceramic coatings to determine the effect of low heat rejection (LHR) operation on engine performance, emissions, and combustion. In comparison to the baseline cooled engine, the LHR engine had lower thermal efficiency, with higher smoke, particulate, and full load carbon monoxide emissions. The unburned hydrocarbon emissions were reduced across the load range. The nitrous oxide emissions increased at some part-load conditions and were reduced slightly at full loads. The poor LHR engine performance was attributed to degraded combustion characterized by less premixed burning, lower heat release rates, and longer combustion duration compared to the baseline cooled engine.

  9. Liquid sprays and flow studies in the direct-injection diesel engine under motored conditions

    Science.gov (United States)

    Nguyen, Hung Lee; Carpenter, Mark H.; Ramos, Juan I.; Schock, Harold J.; Stegeman, James D.

    1988-01-01

    A two dimensional, implicit finite difference method of the control volume variety, a two equation model of turbulence, and a discrete droplet model were used to study the flow field, turbulence levels, fuel penetration, vaporization, and mixing in diesel engine environments. The model was also used to study the effects of engine speed, injection angle, spray cone angle, droplet distribution, and intake swirl angle on the flow field, spray penetration and vaporization, and turbulence in motored two-stroke diesel engines. It is shown that there are optimum conditions for injection, which depend on droplet distribution, swirl, spray cone angle, and injection angle. The optimum conditions result in good spray penetration and vaporization and in good fuel mixing. The calculation presented clearly indicates that internal combustion engine models can be used to assess, at least qualitatively, the effects of injection characteristics and engine operating conditions on the flow field and on the spray penetration and vaporization in diesel engines.

  10. Common Rail Direct Injection Mode of CI Engine Operation with Different Injection Strategies - A Method to Reduce Smoke and NOx Emissions Simultaneously

    Directory of Open Access Journals (Sweden)

    S. V. Khandal

    2018-03-01

    Full Text Available Compression ignition (CI engines are most efficient and robust prime movers used in transportation, power generation applications but suffer from the problems of higher level of exhaust smoke and NOx tailpipe emissions with increased use of fossil fuels. Alternative fuel that replaces diesel and at the same time that result in lower smoke and NOx emissions is presently needed. Therefore the main aim of this experimental study is to lower the smoke and NOx emissions and to use non edible oils that replace the diesel. For this locally available honge biodiesel (BHO and cotton seed biodiesel (BCO were selected as alternative fuels to power CI engine operated in common rail direct injection (CRDI mode. In the first part, optimum fuel injection timing (IT and injection pressure (IP for maximum engine brake thermal efficiency (BTE was obtained. In the second part, performance, combustion and emission characteristics of the CRDI engine was studied with two different fuel injectors having 6 and 7 holes each having 0.2 mm orifice diameter. The CRDI engine results obtained were compared with the baseline date reported. The combustion chamber (CC used for the study was toroidal re-entrant (TRCC. The experimental tests showed that BHO and BCO fuelled CRDI engine showed overall improved performance with 7 hole injector when engine was operated at optimized fuel IT of 10° before top dead centre (bTDC and IP of 900 bar. The smoke emission reduced by 20% to 26% and NOx reduced by 16% to 20% in diesel and biodiesel powered CRDI engine as compared to conventional CI mode besides replacing diesel by biodiesel fuel (BDF.

  11. Fuel-air mixing and distribution in a direct-injection stratified-charge rotary engine

    Science.gov (United States)

    Abraham, J.; Bracco, F. V.

    1989-01-01

    A three-dimensional model for flows and combustion in reciprocating and rotary engines is applied to a direct-injection stratified-charge rotary engine to identify the main parameters that control its burning rate. It is concluded that the orientation of the six sprays of the main injector with respect to the air stream is important to enhance vaporization and the production of flammable mixture. In particular, no spray should be in the wake of any other spray. It was predicted that if such a condition is respected, the indicated efficiency would increase by some 6 percent at higher loads and 2 percent at lower loads. The computations led to the design of a new injector tip that has since yielded slightly better efficiency gains than predicted.

  12. Application of an EGR system in a direct injection diesel engine to reduce NOx emissions

    Science.gov (United States)

    De Serio, D.; De Oliveira, A.; Sodré, J. R.

    2016-09-01

    This work presents the application of an exhaust gas recirculation (EGR) system in a direct injection diesel engine operating with diesel oil containing 7% biodiesel (B7). EGR rates of up to 10% were applied with the primary aim to reduce oxides of nitrogen (NOx) emissions. The experiments were conducted in a 44 kW diesel power generator to evaluate engine performance and emissions for different load settings. The use of EGR caused a peak pressure reduction during the combustion process and a decrease in thermal efficiency, mainly at high engine loads. A reduction of NOx emissions of up to 26% was achieved, though penalizing carbon monoxide (CO) and total hydrocarbons (THC) emissions.

  13. Lube-oil dilution of gasoline direct-injection engines with ethanol fuels; Schmieroelverduennung von direkteinspritzenden Ottomotoren unter Kaltstartrandbedingungen

    Energy Technology Data Exchange (ETDEWEB)

    Kuepper, Carsten; Pischinger, Stefan [RWTH Aachen Univ. (Germany). Lehrstuhl fuer Verbrennungskraftmaschinen (VKA); Artmann, Chrsitina; Rabl, Hans-Peter [Hochschule Regensburg (Germany). Labor fuer Verbrennungsmotoren und Abgasnachbehandlung

    2013-09-15

    Ethanol fuel mixtures account for the majority of biofuels used worldwide. However, their properties make these fuels more difficult to use in cold conditions and especially when starting a cold engine. As part of the FVV research project 'Lubricant Dilution with Ethanol Fuels under Cold Start Conditions', the Institute for Combustion Engines (VKA) at RWTH Aachen University and the Combustion Engines and Emission Control Laboratory at Regensburg University of Applied Sciences have investigated the influence of the ethanol content in fuels on the dilution of the lubricating oil in modern direct-injection gasoline engines. (orig.)

  14. Effect of intake swirl on the performance of single cylinder direct injection diesel engine

    Science.gov (United States)

    Sharma, Vinod Kumar; Mohan, Man; Mouli, Chandra

    2017-11-01

    In the present work, the effect of inlet manifold geometry and swirl intensity on the direct injection (DI) diesel engine performance was investigated experimentally. Modifications in inlet manifold geometry have been suggested to achieve optimized swirl for the better mixing of fuel with air. The intake swirl intensities of modified cylinder head were measured in swirl test rig at different valve lifts. Later, the overall performance of 435 CC DI diesel engine was measured using modified cylinder head. In addition, the performance of engine was compared for both modified and old cylinder head. For same operating conditions, the brake power and brake specific fuel consumption was improved by 6% and 7% respectively with modified cylinder head compared to old cylinder head. The maximum brake power of 9 HP was achieved for modified cylinder head. The results revealed that the intake swirl has great influence on engine performance.

  15. Experimental investigation and combustion analysis of a direct injection dual-fuel diesel-natural gas engine

    Energy Technology Data Exchange (ETDEWEB)

    Carlucci, A.P.; De Risi, A.; Laforgia, D.; Naccarato, F. [Department of Engineering for Innovation, University of Salento, CREA, via per Arnesano, 73100 Lecce (Italy)

    2008-02-15

    A single-cylinder diesel engine has been converted into a dual-fuel engine to operate with natural gas together with a pilot injection of diesel fuel used to ignite the CNG-air charge. The CNG was injected into the intake manifold via a gas injector on purpose designed for this application. The main performance of the gas injector, such as flow coefficient, instantaneous mass flow rate, delay time between electrical signal and opening of the injector, have been characterized by testing the injector in a constant-volume optical vessel. The CNG jet structure has also been characterized by means of shadowgraphy technique. The engine, operating in dual-fuel mode, has been tested on a wide range of operating conditions spanning different values of engine load and speed. For all the tested operating conditions, the effect of CNG and diesel fuel injection pressure, together with the amount of fuel injected during the pilot injection, were analyzed on the combustion development and, as a consequence, on the engine performance, in terms of specific emission levels and fuel consumption. (author)

  16. Optimization experiment of gas oil direct injection valve for CNG dual fuel diesel engine

    Energy Technology Data Exchange (ETDEWEB)

    Kim, B.Y. [Chonnam National University Graduate School, Jeonju (Korea); Park, C. K. [Chonnam National University, Jeonju (Korea)

    1999-04-01

    In this study, we studied for a conversion from diesel engine to natural gas dual fuel engine. For this experimental, we tested about the injection quantity characteristics of pilot valve with the plunger diameter at the retraction volume and investigated to the engine performance and exhaust emissions with the nozzle hole number and injection nozzle diameter. As a result, when the plunger diameter is 7.5 mm at the retraction volume, 25 mm{sup 3}/st, the injection quantity characteristics develop. Also, when a nozzle type is 4*{phi} 0.24, total hydrocarbon(THC) emission reduce at low equivalence ratio. (author). 5 refs., 10 figs., 2 tabs.

  17. Numerical investigation to the dual-fuel spray combustion process in an ethanol direct injection plus gasoline port injection (EDI + GPI) engine

    International Nuclear Information System (INIS)

    Huang, Yuhan; Hong, Guang; Huang, Ronghua

    2015-01-01

    Highlights: • A 5D PDF table was used to model the dual-fuel turbulence–chemistry interactions. • The cooling effect of ethanol direct injection (EDI) was examined. • The higher flame speed of ethanol in EDI + GPI increased the thermal efficiency. • The partially premixed combustion in EDI + GPI reduced the combustion temperature. • Ethanol’s low evaporation rate in low temperature led to incomplete combustion. - Abstract: Ethanol direct injection plus gasoline port injection (EDI + GPI) is a new technology to make the use of ethanol fuel more effective and efficient in spark ignition engines. Multi-dimensional computational fluid dynamics modelling was conducted on an EDI + GPI engine in both single and dual fuelled conditions. The in-cylinder flow field was solved in the realizable k−ε turbulence model with detailed engine geometry. The temporal and spatial distributions of the liquid and vapour fuels were simulated with the spray breakup and evaporation models. The combustion process was modelled with the partially premixed combustion concept in which both mixture fraction and progress variable were solved. The three-dimensional and five-dimensional presumed Probability Density Function (PDF) look-up tables were used to model the single-fraction-mixture and two-fraction-mixture turbulence–chemistry interactions respectively. The model was verified by comparing the numerical and experimental results of spray pattern and cylinder pressure. The simulation results showed that the combustion process of EDI + GPI dual-fuelled condition was partially premixed combustion because of the low evaporation rate of ethanol spray in low temperature environment before combustion. Compared with GPI only, the higher flame speed of ethanol fuel contributed to the greater pressure rise rate and maximum cylinder pressure in EDI + GPI condition, which consequently resulted in higher power output and thermal efficiency. The lower adiabatic flame temperature of

  18. Definition and implementation of internal model control laws for a direct injection engine; Definition et mise en oeuvre de lois de commande a modele interne pour un moteur thermique a injection directe d'essence

    Energy Technology Data Exchange (ETDEWEB)

    Grousson, F.

    2000-10-03

    This study has been achieved in order to improve the direct injection engine control, by using internal model control strategies. Its aim is to optimise the engine performance and to decrease the polluting emissions through a better dynamic control. The use of internal model controls brings robustness in order to face the engine parameter disparity and allows great improvements in the control calibration thanks to a shorter tuning time. The first part gives the outlines of thermic engine operating and focuses on modeling with the final control in view. The second part tackles the implementation of regulation algorithms. Firstly, the air path control uses the state feedback linearization mixed with the predictive control. Secondly, the torque control of the driver's requests is performed with a static inversion using the Jacobian matrix. Finally, a simplified predictive control makes it possible to solve idle speed regulation problems. The last part is devoted to real time and fast proto-typing tests. The main simulation results have been validated through experimental tests on a direct injection car. (author)

  19. Estimation of operational parameters for a direct injection turbocharged spark ignition engine by using regression analysis and artificial neural network

    Directory of Open Access Journals (Sweden)

    Tosun Erdi

    2017-01-01

    Full Text Available This study was aimed at estimating the variation of several engine control parameters within the rotational speed-load map, using regression analysis and artificial neural network techniques. Duration of injection, specific fuel consumption, exhaust gas at turbine inlet, and within the catalytic converter brick were chosen as the output parameters for the models, while engine speed and brake mean effective pressure were selected as independent variables for prediction. Measurements were performed on a turbocharged direct injection spark ignition engine fueled with gasoline. A three-layer feed-forward structure and back-propagation algorithm was used for training the artificial neural network. It was concluded that this technique is capable of predicting engine parameters with better accuracy than linear and non-linear regression techniques.

  20. Modelling soot formation from wall films in a gasoline direct injection engine using a detailed population balance model

    International Nuclear Information System (INIS)

    Wang, Buyu; Mosbach, Sebastian; Schmutzhard, Sebastian; Shuai, Shijin; Huang, Yaqing; Kraft, Markus

    2016-01-01

    Highlights: • Soot formation from a wall film in a GDI engine is simulated. • Spray impingement and wall film evaporation models are added to SRM Engine Suite. • Soot is modelled using a highly detailed population balance model. • Particle size distributions are measured experimentally. • Evolution of wall region is shown in equivalence ratio-temperature diagrams. - Abstract: In this study, soot formation in a Gasoline Direct Injection (GDI) engine is simulated using a Stochastic Reactor Model (SRM Engine Suite) which contains a detailed population balance soot model capable of describing particle morphology and chemical composition. In order to describe the soot formation originating from the wall film, the SRM Engine Suite is extended to include spray impingement and wall film evaporation models. The cylinder is divided into a wall and a bulk zone to resolve the equivalence ratio and temperature distributions of the mixture near the wall. The combustion chamber wall is assumed to exchange heat directly only with the wall zone. The turbulent mixing within each zone and between the two zones are simulated with different mixing models. The effects of key parameters on the temperature and equivalence ratio in the two zones are investigated. The mixing rate between the wall and bulk zone has a significant effect on the wall zone, whilst the mixing rate in the wall zone only has a negligible impact on the temperature and equivalence ratio below a certain threshold. Experimental data are obtained from a four-cylinder, gasoline-fuelled direct injection spark ignition engine operated stoichiometrically. An injection timing sweep, ranging from 120 CAD BTDC to 330 CAD BTDC, is conducted in order to investigate the effect of spray impingement on soot formation. The earliest injection case (330 CAD BTDC), which produces significantly higher levels of particle emissions than any other case, is simulated by the current model. It is found that the in-cylinder pressure

  1. Natural gas in a D. I. diesel engine. A comparison of two different ways. [Direct injection diesel enginer

    Energy Technology Data Exchange (ETDEWEB)

    Jun-ming, Qu; Sorenson, S.C.; Kofoed, E.

    1987-01-01

    A D.I. diesel engine was modified for natural gas operation with pilot injection and with spark ignition so that a comparative analysis of these two different ways of using natural gas could be made. The results of the experiments indicate that for a diesel engine, it is possible that the operating characteristics of a straight natural gas engine are comparable with those of a diesel/gas engine at the same compression ratio and speed. For a dual fuel engine with pilot injection the best diesel/gas ratio by energy content is approximately 20/80 at full load operation. For straight natural gas engine with spark ignition, quality governed natural gas operation has good efficiency but poor NOx emissions. This problem could be improved through throttle controlled operation. These two different ways of using natural gas are best suited to stationary engines.

  2. AN EXPERIMENTAL NOX REDUCTION POTENTIAL INVESTIGATION OF THE PARTIAL HCCI APPLICATION, ON A HIGH PRESSURE FUEL INJECTION EQUIPPED DIESEL ENGINE BY IMPLEMENTING FUMIGATION OF GASOLINE PORT INJECTION

    OpenAIRE

    ERGENÇ, Alp Tekin; YÜKSEK, Levent; ÖZENER, Orkun; IŞIN, Övün

    2016-01-01

    This work investigates the effects of partial HCCI (Homogeneous charge compression ignition) application on today's modern diesel engine tail pipe NOx emissions. Gasoline fumigation is supplied via a port fuel injection system located in the intake port of DI(Direct injection) diesel engine to maintain partial HCCI conditions and also diesel fuel injected directly into the combustion chamber before TDC(Top dead center). A single cylinder direct injection diesel research engine equipped w...

  3. Effects of port fuel injection (PFI) of n-butanol and EGR on combustion and emissions of a direct injection diesel engine

    International Nuclear Information System (INIS)

    Chen, Zheng; Liu, Jingping; Wu, Zhenkuo; Lee, Chiafon

    2013-01-01

    Highlights: • A DI diesel engine with PFI of n-butanol in combination with EGR is investigated. • Butanol concentration and EGR have a coupled impact on combustion process. • A combination of butanol PFI and EGR can break through tradeoff between NOx and soot. • DI diesel with butanol PFI has lower ITE than DI of diesel–butanol blends. - Abstract: An experimental investigation was conducted on a direct injection (DI) diesel engine with exhaust gas recirculation (EGR), coupled with port fuel injection (PFI) of n-butanol. Effects of butanol concentration and EGR rate on combustion, efficiency, and emissions of the tested engine were evaluated, and also compared to a DI mode of diesel–butanol blended fuel. The results show butanol concentration and EGR rate have a coupled impact on combustion process. Under low EGR rate condition, both the peak cylinder pressure and the peak heat release rate increase with increased butanol concentration, but no visible influence was found on the ignition delay. Under high EGR rate condition, however, the peak cylinder pressure and the peak heat release rate both decrease with increased butanol concentration, accompanied by longer ignition delay and longer combustion duration. As regard to the regulated emissions, HC and CO emissions increase with increased butanol concentration, causing higher indicated specific fuel consumption (ISFC) and lower indicated thermal efficiency (ITE). It is also noted that butanol PFI in combination with EGR can change the trade-off relationship between NOx and soot, and simultaneously reduce both into a very low level. Compared with the DI mode of diesel–butanol blended fuel, however, the DI diesel engine with butanol PFI has higher HC and CO emissions and lower ITE. Therefore, future research should be focused on overcoming the identified shortcomings by an improved injection strategy of butanol PFI

  4. Prediction of emissions and exhaust temperature for direct injection diesel engine with emulsified fuel using ANN

    OpenAIRE

    KÖKKÜLÜNK, Görkem; AKDOĞAN, Erhan; AYHAN, Vezir

    2014-01-01

    Exhaust gases have many effects on human beings and the environment. Therefore, they must be kept under control. The International Convention for the Prevention of Pollution from Ships (MARPOL), which is concerned with the prevention of marine pollution, limits the emissions according to the regulations. In Emission Control Area (ECA) regions, which are determined by MARPOL as ECAs, the emission rates should be controlled. Direct injection (DI) diesel engines are commonly used as a prop...

  5. Identifying parameter windows for sulfur removal by direct limestone injection in the rich zone of staged heat engine combustors

    International Nuclear Information System (INIS)

    Colaluca, M.A.

    1990-01-01

    Recent experimental evidence suggests the possibility of sulfur cleanup by direct injection at gas temperatures that do not thermodynamically favor the absorption of sulfur by the limestone. The purpose of this paper is to analytically investigate possible mechanistic explanations of this observed sulfur capture with the goal of evaluating the potential for limestone injection sulfur capture in direct coal fired gas turbine and diesel engine (heat engines) combustion applications. The method was to use current available data on the physical properties of limestone, and the rates of the pertinent reactions, and to develop mathematical models of the processes experienced by the sorbent particles. The models were then used to predict extent of capture at the high-pressure, high-temperature, short residence time conditions of interest. The goal was to first investigate capture in a single-pulse reactor (combustion bomb) and then to extrapolate these results to advanced coal-fired heat engine combustion environments. Model predictions were in good agreement with observed sulfur capture in cold wall combustion bomb studies and suggest that efficient sulfur capture (in excess of 80 percent calcium utilization) may b e possible when limestone sorbents are injected into high-temperature combustion products, even when the gas temperatures exceed the thermodynamically favored temperature window by several hundred kelvins. This behavior is possible because particle temperatures are moderated and held at levels that favor sulfur capture due to the strongly endothermic calcination reaction

  6. Experimental investigations of a single cylinder genset engine with common rail fuel injection system

    Directory of Open Access Journals (Sweden)

    Gupta Paras

    2014-01-01

    Full Text Available Performance and emissions characteristics of compression ignition (CI engines are strongly dependent on quality of fuel injection. In an attempt to improve engine combustion, engine performance and reduce the exhaust emissions from a single cylinder constant speed genset engine, a common rail direct injection (CRDI fuel injection system was deployed and its injection timings were optimized. Results showed that 34°CA BTDC start of injection (SOI timings result in lowest brake specific fuel consumption (BSFC and smoke opacity. Advanced injection timings showed higher cylinder peak pressure, pressure rise rate, and heat release rate due to relatively longer ignition delay experienced.

  7. Regressed relations for forced convection heat transfer in a direct injection stratified charge rotary engine

    Science.gov (United States)

    Lee, Chi M.; Schock, Harold J.

    1988-01-01

    Currently, the heat transfer equation used in the rotary combustion engine (RCE) simulation model is taken from piston engine studies. These relations have been empirically developed by the experimental input coming from piston engines whose geometry differs considerably from that of the RCE. The objective of this work was to derive equations to estimate heat transfer coefficients in the combustion chamber of an RCE. This was accomplished by making detailed temperature and pressure measurements in a direct injection stratified charge (DISC) RCE under a range of conditions. For each specific measurement point, the local gas velocity was assumed equal to the local rotor tip speed. Local physical properties of the fluids were then calculated. Two types of correlation equations were derived and are described in this paper. The first correlation expresses the Nusselt number as a function of the Prandtl number, Reynolds number, and characteristic temperature ratio; the second correlation expresses the forced convection heat transfer coefficient as a function of fluid temperature, pressure and velocity.

  8. The new Mercedes-Benz V6 petrol engine with direct injection; Der neue V6-Ottomotor mit Direkteinspritzung von Mercedes-Benz

    Energy Technology Data Exchange (ETDEWEB)

    Waltner, Anton; Lueckert, Peter; Breitbach, Hermann; Doll, Gerhard; Herwig, Helmut; Kemmler, Roland; Weckenmann, Hartmut [Daimler AG, Stuttgart (Germany)

    2010-07-01

    With the new 6-cylinder engine, Mercedes-Benz has succeeded in implementing a design which, in addition to providing outstanding performance values along with the highest degree of comfort, also appropriately addresses environmental issues and economic viability. The new 60 V-angle and the extremely lightweight construction in the engine area provide an excellent degree of comfort. With third-generation direct injection (DEO3) in conjunction with multi-spark ignition, it was possible to develop new modes of operation thus opening up new areas of the characteristics map with fuel-optimised lean combustion. The brake specific fuel consumption values set new benchmarks for the combustion engine. Together with stop/start technology, shift point adjustment and the systematic reduction of rolling resistance, improvements in fuel consumption up to 20% are possible. All together, this engine design represents an outstanding engine line-up in all target vehicle model series from Mercedes-Benz. Sustainability for the future is also guaranteed through the advantageous injection technology and modularity. (orig.)

  9. Numerical studies of spray breakup in a gasoline direct injection (GDI engine

    Directory of Open Access Journals (Sweden)

    Jafarmadar Samad

    2011-01-01

    Full Text Available The objective of this study is to investigate Spray Breakup process of sprays injected from single and two-hole nozzles for gasoline direct Injection (GDI engines by using three dimensional CFD code. Spray characteristics were examined for spray tip penetration and other characteristics including: the vapor phase concentration distribution and droplet spatial distribution, which were acquired using the computational fluid dynamics (CFD simulation. Results showed that as the hole-axis-angle (γ of the two-hole nozzle decreased, the droplet coalescence increased and vapor mass decreased. The spray with cone angle (θ0 5 deg for single hole nozzle has the longest spray tip penetration and the spray with the γ of 30 deg and spray cone angle θ0=30 deg for two hole nozzles had the shortest one. Also, when the spray cone angle (θ0 and hole-axis-angle (γ increased from 5 to 30 deg, the Sauter mean diameter (SMD decreased for both single-hole and two-hole nozzles used in this study. For a single-hole nozzle, when spray cone angle increased from 5 to 30 deg, the vaporization rate very much because of low level of coalescence. The result of model for tip penetration is good agreement with the corresponding experimental data in the literatures.

  10. Toyota's innovative concept for a SI direct fuel injection system

    Energy Technology Data Exchange (ETDEWEB)

    Matsumura, E.; Kanda, M.; Hattori, F. [Toyota Motor Corporation, Shizuoka (Japan)

    2013-08-01

    To reduce environmental footprint of vehicle, demands have been intensifying for gasoline engines with lower fuel consumption, improved power performance, and lower emissions. The adoption of direct injection technology is rapidly expanding because it is an efficient way to achieve these targets. Originally, gasoline direct injection engines were designed to allow stratified lean combustion, which has a significant fuel consumption reduction effect. However, as exhaust gas emission regulations have become more stringent, the combustion strategy of most gasoline direct injection engines was changed to homogeneous stoichiometric combustion. Stratified lean combustion can nevertheless be used during catalyst heat up phase to fasten it and reduce pollutant emissions. In addition, exhaust gas recirculation (EGR), widely used in Diesel combustion, can also be used in gasoline engine to further reduce fuel consumption by reducing fuel requirement to maintain stoichiometric combustion. Regulations covering the emission of particulate matter (PM), which is an issue of direct injection, have also been strengthened, such as by the introduction of particle number restrictions in Europe. Based on this background, this article introduces the new Toyota direct injection (D-4S) concept that was developed to respond to such requirements. In this concept, combustion speed and air-fuel mixture homogeneity were improved by active usage of spray jets to strengthen the in-cylinder flow. The PM number and oil dilution were significantly reduced by usage of a thin fan-shaped spray formed by a slit nozzle. In addition, this developed slit nozzle has high potential to avoid deposit build-up. Moreover, fast catalyst warming up performance was secured to achieve a low level of emissions compatible with the super ultra low emission vehicle (SULEV) standards in North America. (orig.)

  11. Combustion characteristics of a charcoal slurry in a direct injection diesel engine and the impact on the injection system performance

    International Nuclear Information System (INIS)

    Soloiu, Valentin; Lewis, Jeffery; Yoshihara, Yoshinobu; Nishiwaki, Kazuie

    2011-01-01

    the charcoal is thought to have a paramount role in helping the diffusion type combustion and diminishing the particulate matter formation. As the load was increased, the amount of time it took to notice a decline in engine efficiency decreased. This was due to the injector sticking open which was seen by a sharp increase in the exhaust temperature. The internal flow into the injector had the tendency to form deposits on the injector's seat that were critical to the functionality of the injector. In order to alleviate this problem, a reduced charcoal particle size together with a new injector design were produced resulting in stable engine efficiency at 50% load for a period of 90 min without injector sticking. Even with improvements, the needle's seat into the injector body showed an accelerated wear 4-8 times faster than that in normal operation with diesel fuel and this cannot be sustained for long operational cycles. The investigations have proven that the new charcoal-diesel slurry can produce adequate sprays and burn with very good results in a direct injection diesel engine. The critical aspect of operation is the internal flow into the injector with the tendency to form deposits and wear in the injector. -- Highlights: → Investigations have proven the slurry fuel produces adequate sprays and burns with promising results in a diesel engine. → Pyrolysis of wood was used for the production of charcoal, which was successfully emulsified with diesel oil resulting in low viscosity slurry fuel. → Less smoke produced using the slurry fuel, and the NO x emissions of slurry fuel were improved after injection timing optimization. → Reduced charcoal particle size and new injector design produced stable engine efficiency without injector sticking.

  12. Direct Injection Compression Ignition Diesel Automotive Technology Education GATE Program

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Carl L

    2006-09-25

    The underlying goal of this prqject was to provide multi-disciplinary engineering training for graduate students in the area of internal combustion engines, specifically in direct injection compression ignition engines. The program was designed to educate highly qualified engineers and scientists that will seek to overcome teclmological barriers preventing the development and production of cost-effective high-efficiency vehicles for the U.S. market. Fu1iher, these highly qualified engineers and scientists will foster an educational process to train a future workforce of automotive engineering professionals who are knowledgeable about and have experience in developing and commercializing critical advanced automotive teclmologies. Eight objectives were defmed to accomplish this goal: 1. Develop an interdisciplinary internal co1nbustion engine curriculum emphasizing direct injected combustion ignited diesel engines. 2. Encourage and promote interdisciplinary interaction of the faculty. 3. Offer a Ph.D. degree in internal combustion engines based upon an interdisciplinary cuniculum. 4. Promote strong interaction with indusuy, develop a sense of responsibility with industry and pursue a self sustaining program. 5. Establish collaborative arrangements and network universities active in internal combustion engine study. 6. Further Enhance a First Class educational facility. 7. Establish 'off-campus' M.S. and Ph.D. engine programs of study at various indusuial sites. 8. Extend and Enhance the Graduate Experience.

  13. Etudes théoriques et expérimentales de la combustion dans les moteurs Diesel d'automobiles à injection directe et à préchambre Theoretical and Experimental Research on Combustion in Diesel Automotive Engines with Direct Injection and a Prechamber

    Directory of Open Access Journals (Sweden)

    Douaud A.

    2006-11-01

    Full Text Available Certaines techniques récemment développées pour la modélisation mathématique et les investigations expérimentales sur moteur Diesel sont présentées. On insiste sur l'importance de la validation croisée entre calcul et mesure. Taux d'injection, aérodynamique interne, développement du spray sont analysés en relation avec la géométrie des chambres de combustion. Des exemples, portant principalement sur des considérations de rendement énergétiques et d'émissions polluantes sont présentés à la fois sur le moteur Diesel à préchambre et le moteur Diesel à injection directe. Various techniques developed recently for the mathematical modeling and experimental investigating of diesel engines are described. Emphasis is placed on the importance of crosschecking between computing and measuring. The injection rate, internal aerodynamics and spray development are analyzed in relation to the geometry of combustion chambers. Examples mainly concerning matters of energy efficiency and pollutant emissions are given for diesel engines both with a prechamber and with direct injection.

  14. Experimental facility and methodology for systematic studies of cold startability in direct injection Diesel engines

    Science.gov (United States)

    Pastor, J. V.; García-Oliver, J. M.; Pastor, J. M.; Ramírez-Hernández, J. G.

    2009-09-01

    Cold start at low temperatures in current direct injection (DI) Diesel engines is a problem which has not yet been properly solved and it becomes particularly critical with the current trend to reduce the engine compression ratio. Although it is clear that there are some key factors whose control leads to a proper cold start process, their individual relevance and relationships are not clearly understood. Thus, efforts on optimization of the cold start process are mainly based on a trial-and-error procedure in climatic chambers at low ambient temperature, with serious limitations in terms of measurement reliability during such a transient process, low repeatability and experimental cost. This paper presents a novel approach for an experimental facility capable of simulating real engine cold start, at room temperature and under well-controlled low speed and low temperature conditions. It is based on an optical single cylinder engine adapted to reproduce in-cylinder conditions representative of those of a real engine during start at cold ambient temperatures (of the order of -20 °C). Such conditions must be realistic, controlled and repeatable in order to perform systematic studies in the borderline between ignition success and misfiring. An analysis methodology, combining optical techniques and heat release analysis of individual cycles, has been applied.

  15. Experimental facility and methodology for systematic studies of cold startability in direct injection Diesel engines

    International Nuclear Information System (INIS)

    Pastor, J V; García-Oliver, J M; Pastor, J M; Ramírez-Hernández, J G

    2009-01-01

    Cold start at low temperatures in current direct injection (DI) Diesel engines is a problem which has not yet been properly solved and it becomes particularly critical with the current trend to reduce the engine compression ratio. Although it is clear that there are some key factors whose control leads to a proper cold start process, their individual relevance and relationships are not clearly understood. Thus, efforts on optimization of the cold start process are mainly based on a trial-and-error procedure in climatic chambers at low ambient temperature, with serious limitations in terms of measurement reliability during such a transient process, low repeatability and experimental cost. This paper presents a novel approach for an experimental facility capable of simulating real engine cold start, at room temperature and under well-controlled low speed and low temperature conditions. It is based on an optical single cylinder engine adapted to reproduce in-cylinder conditions representative of those of a real engine during start at cold ambient temperatures (of the order of −20 °C). Such conditions must be realistic, controlled and repeatable in order to perform systematic studies in the borderline between ignition success and misfiring. An analysis methodology, combining optical techniques and heat release analysis of individual cycles, has been applied

  16. 3-D steady state thermomechanical analysis of a piston of a direct injection diesel engine

    International Nuclear Information System (INIS)

    Abid, M.; Bannikov, M.G.; Ali, H.

    2005-01-01

    Piston of internal combustion engine is subjected to the coupled action of the thermal and the mechanical loads. Piston distortion due to temperature nonuniformities has a significant impact on the piston component of the engine friction. In regions of high heat flux, thermal stresses can reach levels that would cause fatigue cracking. Any change of engine design and/or operating conditions resulting in an increased heat flux through the piston may cause engine performance deterioration and even engine failure. This work presents a three-dimensional finite element analysis of a piston of a high power direct injection diesel engine. The goal of such analysis was the prediction of the piston behavior in conditions of the increased brake mean effective pressure and engine speed. Thermal and mechanical loads required for analysis were obtained from the engine cycle simulation. Thermal boundary conditions were determined in the form of the cycle averaged temperature of combustion chamber content and cycle averaged spatially distributed heat transfer coefficients. Mechanical load was represented by the combined gas pressure and inertia forces. Using ANSYS software temperature and stress distributions within the piston body as well as piston deformation were obtained. Analysis was performed for separate as well as combined load. It was shown that contribution of mechanical load is insignificant and can be neglected. Main emphasis is given to scuffing and strength analysis of the piston. Results obtained at various thermal loads are discussed. (author)

  17. Influence of injection pressures till to 1,000 bar on the carburetion in a spark ignition engine with direct injection; Einfluss von Einspritzdruecken bis 1000 bar auf die Gemischbildung in einem Ottomotor mit Direkteinspritzung

    Energy Technology Data Exchange (ETDEWEB)

    Buri, Stefan; Schumann, Florian; Kubach, Heiko; Spicher, Ulrich [Karlsruher Institut fuer Technologie (KIT) (DE). Inst. fuer Kolbenmaschinen (IFKM); Kneifel, Alexander [MTU Friedrichshafen GmbH (Germany)

    2011-07-01

    This paper presents the results of optical investigations of the impact of injection pressures of up to 1000 bar on mixture formation in a spray-guided direct injection engine. The maximum load in stratified operation of an engine with such a spray-guided combustion system is limited by the achievable quality of the mixture. In particular, when using multi hole injectors, the limit of stratified operation is reached rather early, due to comparatively low flow rates and thus insufficient stratification. One measure to increase the flow rate is to increase the injection pressure. The goal of this measure is to generate a more compact stratification, leading to combustion at richer air fuel ratios. This enables reductions of burning duration, hydrocarbon- and particulate emissions. The fundamental impact of increasing the injection pressure from 200 up to 1000 bar on mixture formation was investigated by using LIF- and Mie-scattering in a pressure chamber. Following that, the mixture formation was investigated under real conditions in a single cylinder engine by visualizing the injection process using Mie-scattering. Finally the results of engine operation are compared with those from the pressure chamber. (orig.)

  18. Effect of injection timing on combustion and performance of a direct injection diesel engine running on Jatropha methyl ester

    Energy Technology Data Exchange (ETDEWEB)

    Jindal, S. [Mechanical Engineering Department, College of Technology & Engineering, Maharana Pratap University of Agriculture and Technology, Udaipur 313001 (India)

    2011-07-01

    The present study aims at evaluation of effect of injection timing on the combustion, performance and emissions of a small power diesel engine, commonly used for agriculture purpose, running on pure biodiesel, prepared from Jatropha (Jatropha curcas) vegetable oil. The effect of varying injection timing was evaluated in terms of thermal efficiency, specific fuel consumption, power and mean effective pressure, exhaust temperature, cylinder pressure, rate of pressure rise and the heat release rate. It was found that retarding the injection timing by 3 degrees enhances the thermal efficiency by about 8 percent.

  19. Performance evaluation of common rail direct injection (CRDI engine fuelled with Uppage Oil Methyl Ester (UOME

    Directory of Open Access Journals (Sweden)

    D.N. Basavarajappa

    2015-02-01

    Full Text Available For economic and social development of any country energy is one of the most essential requirements. Continuously increasing price of crude petroleum fuels in the present days coupled with alarming emissions and stringent emission regulations has led to growing attention towards use of alternative fuels like vegetable oils, alcoholic and gaseous fuels for diesel engine applications. Use of such fuels can ease the burden on the economy by curtailing the fuel imports. Diesel engines are highly efficient and the main problems associated with them is their high smoke and NOx emissions.  Hence there is an urgent need to promote the use of alternative fuels in place of high speed diesel (HSD as substitute. India has a large agriculture base that can be used as a feed stock to obtain newer fuel which is renewable and sustainable. Accordingly Uppage oil methyl ester (UOME biodiesel was selected as an alternative fuel. Use of biodiesels in diesel engines fitted with mechanical fuel injection systems has limitation on the injector opening pressure (300 bar. CRDI system can overcome this drawback by injecting fuel at very high pressures (1500-2500 bar and is most suitable for biodiesel fuels which are high viscous. This paper presents the performance and emission characteristics of a CRDI diesel engine fuelled with UOME biodiesel at different injection timings and injection pressures. From the experimental evidence it was revealed that UOME biodiesel yielded overall better performance with reduced emissions at retarded injection timing of -10° BTDC in CRDI mode of engine operation.

  20. Performance evaluation of common rail direct injection (CRDI engine fuelled with Uppage Oil Methyl Ester (UOME

    Directory of Open Access Journals (Sweden)

    D.N. Basavarajappa

    2015-02-01

    Full Text Available For economic and social development of any country energy is one of the most essential requirements. Continuously increasing price of crude petroleum fuels in the present days coupled with alarming emissions and stringent emission regulations has led to growing attention towards use of alternative fuels like vegetable oils, alcoholic and gaseous fuels for diesel engine applications. Use of such fuels can ease the burden on the economy by curtailing the fuel imports. Diesel engines are highly efficient and the main problems associated with them is their high smoke and NOx emissions. Hence there is an urgent need to promote the use of alternative fuels in place of high speed diesel (HSD as substitute. India has a large agriculture base that can be used as a feed stock to obtain newer fuel which is renewable and sustainable. Accordingly Uppage oil methyl ester (UOME biodiesel was selected as an alternative fuel. Use of biodiesels in diesel engines fitted with mechanical fuel injection systems has limitation on the injector opening pressure (300 bar. CRDI system can overcome this drawback by injecting fuel at very high pressures (1500-2500 bar and is most suitable for biodiesel fuels which are high viscous. This paper presents the performance and emission characteristics of a CRDI diesel engine fuelled with UOME biodiesel at different injection timings and injection pressures. From the experimental evidence it was revealed that UOME biodiesel yielded overall better performance with reduced emissions at retarded injection timing of -10° BTDC in CRDI mode of engine operation.

  1. Assessing Rates of Global Warming Emissions from Port- Fuel Injection and Gasoline Direct Injection Engines in Light-Duty Passenger Vehicles

    Science.gov (United States)

    Short, D.; , D., Vi; Durbin, T.; Karavalakis, G.; Asa-Awuku, A. A.

    2013-12-01

    Passenger vehicles are known emitters of climate warming pollutants. CO2 from automobile emissions are an anthropogenic greenhouse gas (GHG) and a large contributor to global warming. Worldwide, CO2 emissions from passenger vehicles are responsible for 11% of the total CO2 emissions inventory. Black Carbon (BC), another common vehicular emission, may be the second largest contributor to global warming (after CO2). Currently, 52% of BC emissions in the U.S are from the transportation sector, with ~10% originating from passenger vehicles. The share of pollutants from passenger gasoline vehicles is becoming larger due to the reduction of BC from diesel vehicles. Currently, the majority of gasoline passenger vehicles in the United States have port- fuel injection (PFI) engines. Gasoline direct injection (GDI) engines have increased fuel economy compared to the PFI engine. GDI vehicles are predicted to dominate the U.S. passenger vehicle market in the coming years. The method of gasoline injection into the combustion chamber is the primary difference between these two technologies, which can significantly impact primary emissions from light-duty vehicles (LDV). Our study will measure LDV climate warming emissions and assess the impact on climate due to the change in U.S vehicle technologies. Vehicles were tested on a light- duty chassis dynamometer for emissions of CO2, methane (CH4), and BC. These emissions were measured on F3ederal and California transient test cycles and at steady-state speeds. Vehicles used a gasoline blend of 10% by volume ethanol (E10). E10 fuel is now found in 95% of gasoline stations in the U.S. Data is presented from one GDI and one PFI vehicle. The 2012 Kia Optima utilizes GDI technology and has a large market share of the total GDI vehicles produced in the U.S. In addition, The 2012 Toyota Camry, equipped with a PFI engine, was the most popular vehicle model sold in the U.S. in 2012. Methane emissions were ~50% lower for the GDI technology

  2. Experimental investigation of timed manifold injection of acetylene in direct injection diesel engine in dual fuel mode

    International Nuclear Information System (INIS)

    Lakshmanan, T.; Nagarajan, G.

    2010-01-01

    The increase in demand and decrease in availability of fossil fuels with more stringent emission norms have led to research in finding an alternative fuel for internal combustion (IC) engines. Among the alternative fuels, gaseous fuels find a great potential. The gaseous fuel taken up for the present study is acetylene, which possesses excellent combustion properties. Preignition is the major problem with this fuel. In the present study, timed manifold injection technique is adopted to induct the fuel into the IC engine. A four-stroke, 4.4 kW diesel engine is selected, with slight modification in intake manifold for holding the gas injector, which is controlled by an electronic control unit (ECU). By using an ECU, an optimized injection timing of 10 o after top dead center and 90 o crank angle duration are arrived. At this condition, experiments were conducted for the various gas flow rates of 110 g/s, 180 g/s and 240 g/s. The performance was nearer to diesel at full load. Oxides of nitrogen, hydrocarbon and carbon monoxide emission decreased due to lean operation with marginal increase in smoke emission. To conclude, a safe operation of acetylene replacement up to 24% was possible with reduction in emission parameters.

  3. Particulate matter emission modelling based on soot and SOF from direct injection diesel engines

    International Nuclear Information System (INIS)

    Tan, P.Q.; Hu, Z.Y.; Deng, K.Y.; Lu, J.X.; Lou, D.M.; Wan, G.

    2007-01-01

    Particulate matter (PM) emission is one of the major pollutants from diesel engines, and it is harmful for human health and influences the atmospheric visibility. In investigations for reducing PM emission, a simulation model for PM emission is a useful tool. In this paper, a phenomenological, composition based PM model of direct injection (DI) diesel engines has been proposed and formulated to simulate PM emission. The PM emission model is based on a quasi-dimensional multi-zone combustion model using the formation mechanisms of the two main compositions of PM: soot and soluble organic fraction (SOF). First, the quasi-dimensional multi-zone combustion model is given. Then, two models for soot and SOF emissions are established, respectively, and after that, the two models are integrated into a single PM emission model. The soot emission model is given by the difference between a primary formation model and an oxidation model of soot. The soot primary formation model is the Hiroyasu soot formation model, and the Nagle and Strickland-Constable model is adopted for soot oxidation. The SOF emission model is based on an unburned hydrocarbons (HC) emission model, and the HC emission model is given by the difference between a HC primary formation model and a HC oxidation model. The HC primary formation model considers fuel injected and mixed beyond the lean combustion limit during ignition delay and fuel effusing from the nozzle sac volume at low pressure and low velocity. In order to validate the PM emission model, experiments were performed on a six cylinder, turbocharged and intercooled DI diesel engine. The simulation results show good agreement with the experimental data, which indicates the validity of the PM emission model. The calculation results show that the distinctions between PM and soot formation rates are mainly in the early combustion stage. The SOF formation has an important influence on the PM formation at lower loads, and soot formation dominates the

  4. Modeling the effects of auxiliary gas injection and fuel injection rate shape on diesel engine combustion and emissions

    Science.gov (United States)

    Mather, Daniel Kelly

    1998-11-01

    The effect of auxiliary gas injection and fuel injection rate-shaping on diesel engine combustion and emissions was studied using KIVA a multidimensional computational fluid dynamics code. Auxiliary gas injection (AGI) is the injection of a gas, in addition to the fuel injection, directly into the combustion chamber of a diesel engine. The objective of AGI is to influence the diesel combustion via mixing to reduce emissions of pollutants (soot and NO x). In this study, the accuracy of modeling high speed gas jets on very coarse computational grids was addressed. KIVA was found to inaccurately resolve the jet flows near walls. The cause of this inaccuracy was traced to the RNG k - ɛ turbulence model with the law-of-the-wall boundary condition used by KIVA. By prescribing the lengthscale near the nozzle exit, excellent agreement between computed and theoretical jet penetration was attained for a transient gas jet into a quiescent chamber at various operating conditions. The effect of AGI on diesel engine combustion and emissions was studied by incorporating the coarse grid gas jet model into a detailed multidimensional simulation of a Caterpillar 3401 heavy-duty diesel engine. The effects of AGI timing, composition, amount, orientation, and location were investigated. The effects of AGI and split fuel injection were also investigated. AGI was found to be effective at reducing soot emissions by increasing mixing within the combustion chamber. AGI of inert gas was found to be effective at reducing emissions of NOx by depressing the peak combustion temperatures. Finally, comparison of AGI simulations with experiments were conducted for a TACOM-LABECO engine. The results showed that AGI improved soot oxidation throughout the engine cycle. Simulation of fuel injection rate-shaping investigated the effects of three injection velocity profiles typical of unit-injector type, high-pressure common-rail type, and accumulator-type fuel injectors in the Caterpillar 3401 heavy

  5. Radial lean direct injection burner

    Science.gov (United States)

    Khan, Abdul Rafey; Kraemer, Gilbert Otto; Stevenson, Christian Xavier

    2012-09-04

    A burner for use in a gas turbine engine includes a burner tube having an inlet end and an outlet end; a plurality of air passages extending axially in the burner tube configured to convey air flows from the inlet end to the outlet end; a plurality of fuel passages extending axially along the burner tube and spaced around the plurality of air passage configured to convey fuel from the inlet end to the outlet end; and a radial air swirler provided at the outlet end configured to direct the air flows radially toward the outlet end and impart swirl to the air flows. The radial air swirler includes a plurality of vanes to direct and swirl the air flows and an end plate. The end plate includes a plurality of fuel injection holes to inject the fuel radially into the swirling air flows. A method of mixing air and fuel in a burner of a gas turbine is also provided. The burner includes a burner tube including an inlet end, an outlet end, a plurality of axial air passages, and a plurality of axial fuel passages. The method includes introducing an air flow into the air passages at the inlet end; introducing a fuel into fuel passages; swirling the air flow at the outlet end; and radially injecting the fuel into the swirling air flow.

  6. Future technology of the spark-ignition engine: spray-guided direct injection with piezo injector; Die Zukunftstechnologie des Ottomotors: Strahlgefuehrte Direkteinspritzung mit Piezo-Injektor

    Energy Technology Data Exchange (ETDEWEB)

    Waltner, A.; Lueckert, P.; Schaupp, U.; Rau, E.; Kemmler, R.; Weller, R. [DaimlerChrysler AG, Stuttgart (Germany)

    2006-07-01

    The completely new-style second-generation direct-injection for spark-ignition engines from Mercedes-Benz offers clear improvements in fuel consumption, power and emission levels. Faced with the necessity of further reducing fuel consumption, primarily in spark-ignition engines, the Mercedes-Benz combustion system represents a significant leap in technology. It was possible to noticeably expand the mapping range in which stratified operation can be used compared with the first generation. This significant improvement in efficiency results in more useable energy and a substantial reduction in consumption in city traffic, and also on cross-country and highway trips at roughly constant speeds. These benefits make themselves felt not only in the test cycle, but also in the real-world consumption achieved by the customer. Development proceeded from the base aspirated engine on the principle of the modular expansion of technology. Since production development of this combustion system was not possible using the hydraulic and ignition components available on the market, a new outward-opening piezo fuel injector had to be developed for production readiness, along with a 200-bar high-pressure fuel system, which is being introduced here for the first time world-wide. The injection spray stability and excellent mixture preparation that it achieves produce an optimally combustible mixture at the spark plug. The potential of multiple injection, along with stability in stratified operation, brings further benefits and possibilities for direct injection in fuel consumption and emissions. (orig.)

  7. Investigation of the effect of heated ethanol fuel on combustion and emissions of an ethanol direct injection plus gasoline port injection (EDI + GPI) engine

    International Nuclear Information System (INIS)

    Huang, Yuhan; Hong, Guang

    2016-01-01

    Highlights: • Effect of EDI heating on the EDI + GPI engine performance was investigated. • CO and HC were significantly reduced and NO was slightly increased by EDI heating. • IMEP and combustion speed were slightly reduced by EDI heating. • EDI heating is effective to address the evaporation and over-cooling issues of EDI + GPI engine. - Abstract: Ethanol direct injection plus gasoline port injection (EDI + GPI) is a new technology to utilise ethanol fuel more efficiently and flexibly in spark ignition engines. One issue needs to be addressed in the development of EDI + GPI is the ethanol fuel’s low vapour pressure and large latent heat which slow down the ethanol’s evaporation and result in the mixture unready for combustion by the time of spark ignition and the consequent increase of CO and HC emissions. Heating the ethanol fuel to be directly injected (EDI heating) has been proposed to address this issue. This paper reports the investigation of the effect of EDI heating on the combustion and emissions of a research engine equipped with EDI + GPI. The results showed that EDI heating effectively reduced the CO and HC emissions of the engine due to the increase of evaporation rate and reduced fuel impingement and local over-cooling. The reduction of CO and HC became more significant with the increase of ethanol ratio. When the temperature of the ethanol fuel was increased by 40 °C, the CO and HC were reduced by as much as 43% and 51% respectively in EDI only condition at the original spark timing of 15 CAD BTDC, and 15% and 47% respectively at the minimum spark advance for best torque (MBT) timing of 19 CAD BTDC. On the other hand, the NO emission was slightly increased, but still much smaller than that in GPI only condition due to the strong cooling effect and low combustion temperature of EDI. The IMEP and combustion speed were slightly reduced by EDI heating due to the decrease of injector fuel flow rate and spray collapse of flash-boiling. The

  8. The Effect of Ethanol-Diesel Blends on The Performance of A Direct Injection Diesel Engine

    Directory of Open Access Journals (Sweden)

    Arifin Nur

    2012-07-01

    Full Text Available The experiment was conducted on a conventional direct injection diesel engine. Performance test was carried out to evaluate the performance and emission characteristics of a conventional diesel engine that operates on ethanol-diesel blends. The test procedure was performed by coupling the diesel engine on the eddy current dynamometer. Fuel consumption was measured using the AVL Fuel Balance, and a hotwire anemometer was used to measure the air consumption. Some of the emission test devices were mounted on the exhaust pipe. The test of fuel variations started from 100% diesel fuel (D100 to 2.5% (DE2.5, 5% (DE5, 7.5% (DE7.5, and 10% (DE10 ethanol additions. Performance test was conducted at 1500 rpm with load variations from 0 to 60 Nm by increasing the load on each level by 10 Nm. The addition of 5% ethanol to diesel (DE5 increased the average pressure of combustion chamber indication to 48% as well as reduced the specific fuel consumption to 9.5%. There were better exhaust emission characteristics at this mixture ratio than diesel engine which used pure diesel fuel (D100, the reduction of CO to 37%, HC to 44% and opacity to 15.9%.

  9. Preliminary study on the control of direct injection diesel engine for better fuel flexibility and emissions control. Pt. 1 and 2

    Energy Technology Data Exchange (ETDEWEB)

    Egnell, R.; Kassem, N.; Bohlin, T.

    1985-01-01

    This report summarizes the results of a preliminary study on turbocharged direct injection diesel engines. Part I reviews the qualitative dynamic aspects of turbocharged diesel engine and the factors that affect its transient behaviour. It gives a brief account of the model structure and the interrelationships between the different components of the model as well as the different types of engine models and the methods of simulation. The transient response of a turbocharged engine under changing load, speed, and ambient conditions are discussed. Methods to improve the transient response, thus reducing fuel consumption and smoke emissions are briefly reviewed. Finally, both conventional and advanced control strategies are discussed with emphasis on the control of fuel injection (Delta-control), injection time (Alfa-control), and exhaust gas recirculation (EGR-control). Part II (in Swedish) consists of a literature survey on hardware components such as sensors, actuators, and injection systems that are, or expect to be, available with reasonable commercial costs. The objective of this survey is to provide the grounds on which to decide if these components satisfy the requirements of electronic control systems. Part III (in Swedish) discusses the transient response measurements obtained from two sets of experiments conducted on a six-cylinder motor working under varying conditions of load and speed. The objective of the first set of experiments was to quantify the difference in ignition delay between the transient and steady state operating conditions. The second set of experiments were aimed to provide a basis on which the engine efficiency obtained under transient conditions can be compared to that obtained from a single-cylinder motor working under steady state conditions.

  10. Performance of an Otto cycle motor with natural gas direct injection; Desempenho de um motor ciclo Otto com injecao direta de gas natural

    Energy Technology Data Exchange (ETDEWEB)

    Barbosa, Cleiton Rubens Formiga

    1997-07-01

    A Otto cycle engine with natural gas direct injection, during the inlet stroke, was submitted to runs with full power in a Foucaut dynamometer. The results obtained show a increase in the volumetric efficiency of the engine with natural gas direct injection when compared with natural gas injection applied in the inlet manifold, upstream of the throttle butterfly. In the conversion to natural gas direct injection, the technical characteristics were not changed. A kit for natural gas direct injection, with electronic management was located on the cylinder head of the test engine. Maintaining the pressure constant in the natural gas fuel line, using a reduction valve, the mass of fuel injected into the cylinder was regulated, varying the opening time of the solenoid valve fuel injector. Engine performance data is compared, emphasizing the factors that contribute to this increase in relative volumetric efficiency. Modifications are made to maximize the power of the engine with natural gas direct injection. (author)

  11. Optimization of the combustion system of a medium duty direct injection diesel engine by combining CFD modeling with experimental validation

    International Nuclear Information System (INIS)

    Benajes, Jesus; Novella, Ricardo; Pastor, Jose Manuel; Hernández-López, Alberto; Hasegawa, Manabu; Tsuji, Naohide; Emi, Masahiko; Uehara, Isshoh; Martorell, Jordi; Alonso, Marcos

    2016-01-01

    Highlights: • A DOE-based optimization of the combustion system of a CI engine has been performed. • Improving efficiency controlling emissions needs optimizing bowl design and settings. • Swirl-supported with re-entrant bowl combustion system is required after optimizing. • Computationally optimized combustion system has been validated by engine tests. - Abstract: The research in the field of internal combustion engines is currently driven by the needs of decreasing fuel consumption and CO_2 emissions, while fulfilling the increasingly stringent pollutant emissions regulations. In this framework, this research work focuses on describing a methodology for optimizing the combustion system of Compression Ignition (CI) engines, by combining Computational Fluid Dynamics (CFD) modeling, and the statistical Design of Experiments (DOE) technique known as Response Surface Method (RSM). As a key aspect, in addition to the definition of the optimum set of values for the input parameters, this methodology is extremely useful to gain knowledge on the cause/effect relationships between the input and output parameters under investigation. This methodology is applied in two sequential studies to the optimization of the combustion system of a 4-cylinder 4-stroke Medium Duty Direct Injection (DI) CI engine, minimizing the fuel consumption while fulfilling the emission limits in terms of NO_x and soot. The first study targeted four optimization parameters related to the engine hardware including piston bowl geometry, injector nozzle configuration and mean swirl number (MSN) induced by the intake manifold design. After the analysis of the results, the second study extended to six parameters, limiting the optimization of the engine hardware to the bowl geometry, but including the key air management and injection settings. For both studies, the simulation plans were defined following a Central Composite Design (CCD), providing 25 and 77 simulations respectively. The results

  12. Characteristics of Early Flame Development in a Direct-Injection Spark-Ignition CNG Engine Fitted with a Variable Swirl Control Valve

    Directory of Open Access Journals (Sweden)

    Abd Rashid Abd Aziz

    2017-07-01

    Full Text Available An experimental study was conducted to investigate the effect of the structure of the induction flow on the characteristics of early flames in a lean-stratified and lean-homogeneous charge combustion of compressed natural gas (CNG fuel in a direct injection (DI engine at different engine speeds. The engine speed was varied at 1500 rpm, 1800 rpm and 2100 rpm, and the ignition timing was set at a 38.5° crank angle (CA after top dead center (TDC for all conditions. The engine was operated in a partial-load mode and a homogeneous air/fuel charge was achieved by injecting the fuel early (before the intake valve closure, while late injection during the compression stroke was used to produce a stratified charge. Different induction flow structures were obtained by adjusting the swirl control valves (SCV. Using an endoscopic intensified CCD (ICCD camera, flame images were captured and analyzed. Code was developed to analyze the level of distortion of the flame and its wrinkledness, displacement and position relative to the spark center, as well as the flame growth rate. The results showed a higher flame growth rate with the flame kernel in the homogeneous charge, compared to the stratified combustion case. In the stratified charge combustion scenario, the 10° SCV closure (medium-tumble resulted in a higher early flame growth rate, whereas a homogeneous charge combustion (characterized by strong swirl resulted in the highest rate of flame growth.

  13. Experimental Studies of Diestrol-Micro Emulsion Fuel in a Direct Injection Compression Ignition Engine under Varying Injection Pressures and Timings

    Science.gov (United States)

    Kannan, Gopal Radhakrishnan

    2018-02-01

    The research work on biodiesel becomes more attractive in the context of limited availability of petroleum fuels and rapid increase of harmful emissions from diesel engine using conventional fossil fuels. The present investigation has dealt with the influence of biodiesel-diesel-ethanol (diestrol) water micro emulsion fuel (B60D20E20M) on the performance, emission and combustion characteristics of a diesel engine under different injection pressure and timing. The results revealed that the maximum brake thermal efficiency of 32.4% was observed at an injection pressure of 260 bar and injection timing of 25.5°bTDC. In comparison with diesel, micro emulsion fuel showed reduction in carbon monoxide (CO) and total hydrocarbon (THC) by 40 and 24%, respectively. Further, micro emulsion fuel decreased nitric oxide (NO) emission and smoke emission by 7 and 20.7%, while the carbon dioxide (CO2) emission is similar to that of diesel.

  14. Modification of piston bowl geometry and injection strategy, and investigation of EGR composition for a DME-burning direct injection engine

    Directory of Open Access Journals (Sweden)

    Kianoosh Shojae

    2017-01-01

    Full Text Available The amount of pollutant gases in the atmosphere has reached a critical state due to an increase in industrial development and the rapid growth of automobile industries that use fossil fuels. The combustion of fossil fuels produces harmful gases such as carbon dioxide, nitrogen monoxide (NO, soot, particulate matter (PM, etc. The use of Dimethyl Ether (DME biofuel in diesel engines or other combustion processes have been highly regarded by researchers. Studies show that the use of pure DME in automotive engines will be possible in the near future. The present work evaluated the environmental and performance effects of changing the injection strategy (time and temperature, piston bowl geometry, and exhaust gas recirculation (EGR composition for a DME-burning engine. The modification of piston bowl parameters and engine simulation were numerically performed by using AVL fire CFD code. For model validation, the calculated mean pressure and rate of heat released (RHR were compared to the experimental data and the results showed a good agreement (under a 70% load and 1200-rpm engine speed. It was found that retarding injection timing (reduction in in-cylinder temperature, consequently caused a reduction in NO emissions and increased soot formation, reciprocally; this occurred because of a reduction in temperature and a lower soot oxidation in the combustion chamber. It became clear that 3 deg before top dead center (BTDC was the appropriate injection timing for the DME-burning heavy duty diesel engine running under 1200 rpm. Also, the parametrical modification of the piston bowl geometry and the simultaneous decrease of Tm (piston bowl depth and R3 (bowl inner radius lengths were associated with lower exhaust NO emissions. For the perfect utilization of DME fuel in an HD diesel engine, the suggested proper lengths of Tm and R3 were 0.008 and 0.0079 m, respectively. Furthermore, various EGR compositions for the reduction of exhaust NO were investigated

  15. A Combined Experimental and Computational Fluid Dynamics Investigation of Particulate Matter Emissions from a Wall-Guided Gasoline Direct Injection Engine

    Directory of Open Access Journals (Sweden)

    Davide D. Sciortino

    2017-09-01

    Full Text Available The latest generation of high-efficiency gasoline direct injection (GDI engines continues to be a significant source of dangerous ultra-fine particulate matter (PM emissions. The forthcoming advent in the 2017–2020 timeframe of the real driving emission (RDE standards affords little time for the identification of viable solutions. The present research work aims to contribute towards a much-needed improved understanding of the process of PM formation in theoretically-homogeneous stoichiometric spark-ignition combustion. Experimental measurements of engine-out PM have been taken from a wall-guided GDI engine operated at part-load; through parallel computational fluid dynamics (CFD simulations of the test-engine, the process of mixture preparation was investigated. About 80% of the total particle number is emitted on average in the 5–50 nm range, with the vast majority being below the regulated lower limit of 23 nm. The results suggest that both improved charge homogeneity and lower peak combustion temperature contribute to lower particle number density (PNDen and larger particle size, as engine speed and load increase. The effect of engine load is stronger and results from greater injection pressure through better fuel droplet atomisation. Increases in pre-combustion homogeneity of 6% are associated with one order of magnitude reductions of PNDen. A simplified two-equation functional model was developed, which returns satisfactory qualitative predictions of PNDen as a function of basic engine control variables.

  16. Experimental characterization of cooled EGR in a gasoline direct injection engine for reducing fuel consumption and nitrogen oxide emission

    Science.gov (United States)

    Park, Sang-Ki; Lee, Jungkoo; Kim, Kyungcheol; Park, Seongho; Kim, Hyung-Man

    2015-11-01

    The emphasis on increasing fuel economy and reducing emissions is increasing. Attention has turned to how the performance of a gasoline direct injection (GDI) engine can be improved to achieve lower fuel consumption and NOx emission. Therefore, positive effects can reduce fuel consumption and NOx emission as well as knock suppression. The cooled exhaust gas recirculation (EGR) ranges within the characteristic map are characterized from the experimental results at various speeds and brake mean effective pressures in a GDI engine. The results show that the application of cooled EGR system brought in 3.63 % reduction as for the fuel consumption and 4.34 % as for NOx emission.

  17. Performance and exhaust emission characteristics of direct-injection Diesel engine when operating on shale oil

    International Nuclear Information System (INIS)

    Labeckas, Gvidonas; Slavinskas, Stasys

    2005-01-01

    This article presents the comparative bench testing results of a naturally aspirated, four stroke, four cylinder, water cooled, direct injection Diesel engine when running on Diesel fuel and shale oil that is produced in Estonia from local oil shale. The purpose of this research is to investigate the possibility of practical usage of the shale oil as the alternative fuel for a high speed Diesel engine as well as to evaluate the combustion efficiency, brake specific fuel consumption, emission composition changes and the smoke opacity of the exhausts. Test results show that when fuelling a fully loaded engine with shale oil, the brake specific fuel consumption at the maximum torque and rated power is correspondingly higher by 12.3% and 20.4%. However, the brake thermal efficiencies do not differ widely and their maximum values remain equal to 0.36-0.37 for Diesel fuel and 0.32-0.33 for shale oil. The total nitrogen oxide emissions from the shale oil at engine partial loads remain considerably lower although when running at the maximum torque and rated power, the NO x emissions become correspondingly higher by 21.8% and 27.6%. The smoke opacity of the fully loaded engine at a wide range of speeds is lower by 30-35%, whereas the carbon monoxide and unburned hydrocarbon emissions in the exhausts at moderate and full load regimes do not undergo significant changes

  18. Performance and Economics of Catalytic Glow Plugs and Shields in Direct Injection Natural Gas Engines for the Next Generation Natural Gas Vehicle Program: Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Mello, J. P.; Bezaire, D.; Sriramulu, S.; Weber, R.

    2003-08-01

    Subcontractor report details work done by TIAX and Westport to test and perform cost analysis for catalytic glow plugs and shields for direct-injection natural gas engines for the Next Generation Natural Gas Vehicle Program.

  19. Delphi's new direct acting common rail injection system; Das neue Direct Acting Common Rail System von Delphi

    Energy Technology Data Exchange (ETDEWEB)

    Schoeppe, Detlev; Zuelch, Stefan; Geurts, Derk; Gris, Christian; Jorach, Rainer W. [Delphi Diesel Systems, Europe (United Kingdom)

    2009-07-01

    With the serial start of the Direct Acting Common Rail injection system with 2.000 bar Delphi Diesel Systems could supplement its product portfolio with a valuable component. In Delphi's directly propelled Common Rail injector, the Injection needle directly is set in operation with the help of a piezo-ceramic actuator instead of only controlling this with a conventional servo-hydraulic circuit indirectly. This enables a fast opening and closing of the nozzle needle possible independently from the rail pressure. The process of injection is controllable accurately at any time with the again developed two-stage needle movement amplifier. The additionally in the injector integrated fuel storage works as a 'Rail in the Injector' and improves the quality particularly during multiple injection. The injector completely works leakage-free and thereby helps to reach the future CO{sub 2} targets. The use of piezo-actuators as driving force behind the directly working injector leads to a set of requirements to the electronics. A control electronics was developed in order to head optimally the Direct Acting Injector. The sum of all advantages of the Direct Acting of CR systems enables lowest emissions with simultaneously small fuel consumption while new dimensions are reached with power density and engine torque. The authors of the contribution under consideration report on the construction, on the work principle of the Direct Acting CR system and on its performance characteristics as a basis for the premium diesel engine.

  20. Diesel Engine Convert to Port Injection CNG Engine Using Gaseous Injector Nozzle Multi Holes Geometries Improvement: A Review

    OpenAIRE

    Semin; Abdul R. Ismail; Rosli A. Bakar

    2009-01-01

    The objective of this study was to review the previous research in the development of gaseous fuel injector for port injection CNG engine converted from diesel engine. Problem statement: The regular development of internal combustion engines change direction to answer the two most important problems determining the development trends of engines technology and in particular, their combustion systems. They were environmental protection against emission and noise, shortage of hydrocarbon fuels, ...

  1. Radial oil injection applied to main engine bearings: evaluation of injection control rules

    DEFF Research Database (Denmark)

    Estupiñan, EA; Santos, Ilmar

    2012-01-01

    , the dynamic behaviour of the main bearing of a medium-size engine is theoretically analysed when the engine operates with controllable radial oil injection and four different injection control rules. The theoretical investigation is based on a single-cylinder combustion engine model. The performance......The performance of main bearings in a combustion engine affects key functions such as durability, noise and vibration. Thus, with the aim of reducing friction losses and vibrations between the crankshaft and the bearings, the work reported here evaluates different strategies for applying...... controllable radial oil injection to main crankshaft journal bearings. In an actively lubricated bearing, conventional hydrodynamic lubrication is combined with controllable hydrostatic lubrication, where the oil injection pressures can be modified depending on the operational conditions. In this study...

  2. Three-dimensional analysis of internal flow characteristics in the injection nozzle tip of direct-injection diesel engines; Sanjigen suchi kaiseki ni yoru DI diesel kikan no nenryo funsha nozzle nai ryudo tokusei no kaimei

    Energy Technology Data Exchange (ETDEWEB)

    Ogawa, H; Matsui, Y; Kimura, S [Nissan Motor Co. Ltd. Tokyo (Japan)

    1997-10-01

    To reduce the exhaust emissions and fuel consumption of direct-injection diesel engines, it is essential to optimize the fuel injection equipment closely related to combustion and emission characteristics. In this study, three-dimensional computation has been applied to investigate the effects of the injection nozzle specifications (e.g., sac volume, round shape at the inlet of the nozzle hole) and needle tip deviation on internal flow characteristics. The computational results revealed that the effects of the nozzle specifications and needle tip deviation with a smaller needle lift on internal flow characteristics and a general approach to optimize the injection nozzle specifications were obtained. 3 refs., 10 figs., 1 tab.

  3. Influence of alumina oxide nanoparticles on the performance and emissions in a methyl ester of neem oil fuelled direct injection diesel engine

    Directory of Open Access Journals (Sweden)

    Balaji Gnanasikamani

    2017-01-01

    Full Text Available The experimental investigation of the influence of Al2O3 nanoadditive on performance and emissions in a methyl ester of neem oil fueled direct injection Diesel engine is reported in this paper. The Al2O3 nanoparticles are mixed in various proportions (100 to 300 ppm with methyl ester of neem oil. The performance and emissions are tested in a single cylinder computerized, 4-stroke, stationary, water-cooled Diesel engine of 3.5 kW rated power. Results show that the nanoadditive is effective in increasing the performance and controlling the NO emissions of methyl ester of neem oil fueled Diesel engines.

  4. Ignition assist systems for direct-injected, diesel cycle, medium-duty alternative fuel engines: Final report phase 1

    Energy Technology Data Exchange (ETDEWEB)

    Chan, A.K.

    2000-02-23

    This report is a summary of the results of Phase 1 of this contract. The objective was to evaluate the potential of assist technologies for direct-injected alternative fuel engines vs. glow plug ignition assist. The goal was to demonstrate the feasibility of an ignition system life of 10,000 hours and a system cost of less than 50% of the glow plug system, while meeting or exceeding the engine thermal efficiency obtained with the glow plug system. There were three tasks in Phase 1. Under Task 1, a comprehensive review of feasible ignition options for DING engines was completed. The most promising options are: (1) AC and the ''SmartFire'' spark, which are both long-duration, low-power (LDLP) spark systems; (2) the short-duration, high-power (SDHP) spark system; (3) the micropilot injection ignition; and (4) the stratified charge plasma ignition. Efforts concentrated on investigating the AC spark, SmartFire spark, and short-duration/high-power spark systems. Using proprietary pricing information, the authors predicted that the commercial costs for the AC spark, the short-duration/high-power spark and SmartFire spark systems will be comparable (if not less) to the glow plug system. Task 2 involved designing and performing bench tests to determine the criteria for the ignition system and the prototype spark plug for Task 3. The two most important design criteria are the high voltage output requirement of the ignition system and the minimum electrical insulation requirement for the spark plug. Under Task 3, all the necessary hardware for the one-cylinder engine test was designed. The hardware includes modified 3126 cylinder heads, specially designed prototype spark plugs, ignition system electronics, and parts for the system installation. Two 3126 cylinder heads and the SmartFire ignition system were procured, and testing will begin in Phase 2 of this subcontract.

  5. Effect of Fuel Composition on Particulate Matter Emissions from a Gasoline Direct Injection Engine

    Science.gov (United States)

    Smallwood, Bryden Alexander

    The effects of fuel composition on reducing PM emissions were investigated using a Ford Focus wall-guided gasoline direct injection engine (GDI). Initial results with a 65% isooctane and 35% toluene blend showed significant reductions in PM emissions. Further experiments determined that this decrease was due to a lack of light-end components in that fuel blend. Tests with pentane content lower than 15% were found to have PN concentrations 96% lower than tests with 20% pentane content. This indicates that there is a shift in mode of soot production. Pentane significantly increases the vapour pressure of the fuel blend, potentially resulting in surface boiling, less homogeneous mixtures, or decreased fuel rebound from the piston. PM mass measurements and PN Index values both showed strong correlations with the PN concentration emissions. In the gaseous exhaust, THC, pentane, and 1,3 butadiene showed strong correlations with the PM emissions.

  6. Effect of fuel injection pressure and injection timing of Karanja biodiesel blends on fuel spray, engine performance, emissions and combustion characteristics

    International Nuclear Information System (INIS)

    Agarwal, Avinash Kumar; Dhar, Atul; Gupta, Jai Gopal; Kim, Woong Il; Choi, Kibong; Lee, Chang Sik; Park, Sungwook

    2015-01-01

    Highlights: • Effect of FIP on microscopic spray characteristics. • Effect of FIP and SOI timing on CRDI engine performance, emissions and combustion. • Fuel injection duration shortened, peak injection rate increased with increasing FIP. • SMD (D 32 ) and AMD (D 10 ) of fuel droplets decreased for lower biodiesel blends. • Increase in biodiesel blend ratio and FIP, fuel injection duration decreased. - Abstract: In this investigation, effect of 10%, 20% and 50% Karanja biodiesel blends on injection rate, atomization, engine performance, emissions and combustion characteristics of common rail direct injection (CRDI) type fuel injection system were evaluated in a single cylinder research engine at 300, 500, 750 and 1000 bar fuel injection pressures at different start of injection timings and constant engine speed of 1500 rpm. The duration of fuel injection slightly decreased with increasing blend ratio of biodiesel (Karanja Oil Methyl Ester: KOME) and significantly decreased with increasing fuel injection pressure. The injection rate profile and Sauter mean diameter (D 32 ) of the fuel droplets are influenced by the injection pressure. Increasing fuel injection pressure generally improves the thermal efficiency of the test fuels. Sauter mean diameter (D 32 ) and arithmetic mean diameter (D 10 ) decreased with decreasing Karanja biodiesel content in the blend and significantly increased for higher blends due to relatively higher fuel density and viscosity. Maximum thermal efficiency was observed at the same injection timing for biodiesel blends and mineral diesel. Lower Karanja biodiesel blends (up to 20%) showed lower brake specific hydrocarbon (BSHC) and carbon monoxide (BSCO) emissions in comparison to mineral diesel. For lower Karanja biodiesel blends, combustion duration was shorter than mineral diesel however at higher fuel injection pressures, combustion duration of 50% blend was longer than mineral diesel. Up to 10% Karanja biodiesel blends in a CRDI

  7. Effect of palm methyl ester-diesel blends performance and emission of a single-cylinder direct-injection diesel engine

    Science.gov (United States)

    Said, Mazlan; Aziz, Azhar Abdul; Said, Mohd Farid Muhamad

    2012-06-01

    The purpose of this study is to investigate engine performance and exhaust emission when using several blends of neat palm oil methyl ester (POME) with conventional diesel (D2) in a small direct injection diesel engine, and to compare the outcomes to that of the D2 fuel. Engine performances, exhaust emissions, and some other important parameters were observed as a function of engine load and speed. In addition, the effect of modifying compression ratio was also carried out in this study. From the engine experimental work, neat and blended fuels behaved comparably to diesel (D2) in terms of fuel consumption, thermal efficiency and rate of heat released. Smoke density showed better results than that emitted by D2, operating under similar conditions due to the presence of inherited oxygen and lower sulphur content in the biofuel and its blends. The emissions of CO, CO2, and HC were also lower using blended mixtures and in its neat form. However, NOx concentrations were found to be slight higher for POME and its blends and this was largely due to higher viscosity of POME and possibly the presence of nitrogen in the palm methyl ester. General observation indicates that biofuel blends can be use without many difficulties in this type of engine but for optimized operation minor modifications to the engine and its auxiliaries are required.

  8. Direct vessel inclined injection system for reduction of emergency core coolant direct bypass in advanced reactors

    International Nuclear Information System (INIS)

    Yoon, Sang H.; Lee, Jong G.; Suh, Kune Y.

    2006-01-01

    Multidimensional thermal hydraulics in the APR1400 (Advanced Power Reactor 1400 MWe) downcomer during a large-break loss-of-coolant accident (LBLOCA) plays a pivotal role in determining the capability of the safety injection system. APR1400 adopts the direct vessel injection (DVI) method for more effective core penetration of the emergency core cooling (ECC) water than the cold leg injection (CLI) method in the OPR1000 (Optimized Power Reactor 1000 MWe). The DVI method turned out to be prone to occasionally lack in efficacious delivery of ECC to the reactor core during the reflood phase of a LBLOCA, however. This study intends to demonstrate a direct vessel inclined injection (DVII) method, one of various ideas with which to maximize the ECC core penetration and to minimize the direct bypass through the break during the reflood phase of a LBLOCA. The 1/7 scaled down THETA (Transient Hydrodynamics Engineering Test Apparatus) tests show that a vertical inclined nozzle angle of the DVII system increases the downward momentum of the injected ECC water by reducing the degree of impingement on the reactor downcomer, whereby lessening the extent of the direct bypass through the break. The proposed method may be combined with other innovative measures with which to ensure an enough thermal margin in the core during the course of a LBLOCA in APR1400

  9. Optimization of operating conditions in the early direct injection premixed charge compression ignition regime

    NARCIS (Netherlands)

    Boot, M.D.; Luijten, C.C.M.; Rijk, E.P.; Albrecht, B.A.; Baert, R.S.G.

    2009-01-01

    Early Direct Injection Premixed Charge Compression Ignition (EDI PCCI) is a widely researched combustion concept, which promises soot and CO2 emission levels of a spark-ignition (SI) and compression-ignition (CI) engine, respectively. Application of this concept to a conventional CI engine using a

  10. COMBUSTION ANALYSIS OF ALGAL OIL METHYL ESTER IN A DIRECT INJECTION COMPRESSION IGNITION ENGINE

    Directory of Open Access Journals (Sweden)

    HARIRAM V.

    2013-02-01

    Full Text Available Algal oil methyl ester was derived from microalgae (Spirulina sp. The microalga was cultivated in BG 11 media composition in a photobioreactor. Upon harvesting, the biomass was filtered and dried. The algal oil was obtained by a two step solvent extraction method using hexane and ether solvent. Cyclohexane was added to biomass to expel the remaining algal oil. By this method 92% of algal oil is obtained. Transesterification process was carried out to produce AOME by adding sodium hydroxide and methanol. The AOME was blended with straight diesel in 5%, 10% and 15% blend ratio. Combustion parameters were analyzed on a Kirloskar single cylinder direct injection compression ignition engine. The cylinder pressure characteristics, the rate of pressure rise, heat release analysis, performance and emissions were studied for straight diesel and the blends of AOME’s. AOME 15% blend exhibits significant variation in cylinder pressure and rate of heat release.

  11. Preliminary study on the combustion and emission in a direct injection LPG spark ignition engine

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Seungmook; Lee, Seokhwan [Korea Institute of Machinery and Materials (Korea, Republic of)

    2010-07-01

    In the energy sector, with the implementation of stringent regulations on combustion emissions and the depletion of conventional fuels, there is an important need for low carbon fuel and advanced engine technology. Korea is the country with the most LPG vehicles in the world and the aim of this study, performed by the Korea Institute of Machinery and Materials, is to compare the performance of LPG direct injection spark ignition (DISI) with gasoline DISI. Heat release analyses were conducted to determine the combustion characteristics of both systems and experiments were performed to determine gaseous and nanoparticle emissions. Results showed that LPG provides a better thermal efficiency than gasoline and that THC, NOx, and particulate emissions were lower for LPG than for gasoline. This study demonstrated that LPG DISI can provide better combustion efficiency and lower emissions than gasoline DISI.

  12. Preliminary study on the control of direct injection diesel engine for better fuel flexibility and emissions control. Pt. 3

    Energy Technology Data Exchange (ETDEWEB)

    Egnell, R.; Kassem, N.; Bohlin, T.

    1985-01-01

    This report summarizes the results of a preliminary study on turbocharged direct injection diesel engines. The objectives and scope of this study are: 1. To explore the potential of using electronic control systems based on dynamic models of the engine in order to reduce fuel consumption, while maintaining good driveability. 2. To analyze the transient response of a turbocharged diesel engine based on experimental data collected from one of SAAB-SCANIA's test cells. 3. To survey the hardware components that would satisfy the requirements of the electronic control systems mentioned above. Part III discusses the transient response measurements obtained from two sets of experiments conducted on a six-cylinder motor working under varying conditions of load and speed. The objective of the first set of experiments was to quantify the difference in ignition delay between the transient and steady state operating conditions. The second set of experiments were aimed to provide a basis on which the engine efficiency obtained under transient conditions can be compared to that obtained from a single-cylinder motor working under steady state conditions.

  13. Experimental investigation of gasoline fumigation in a single cylinder direct injection (DI) diesel engine

    International Nuclear Information System (INIS)

    Sahin, Z.; Durgun, O.; Bayram, C.

    2008-01-01

    In the presented study, the effects of gasoline fumigation have been investigated experimentally in a single cylinder direct injection (DI) diesel engine. Gasoline has been introduced into the inlet air flow using an elementary carburetor and no other modification on the engine has been done. The effects of 2%, 4%, 6%, 8% and 10% (by vol.) gasoline fumigation have been investigated experimentally at the speeds of (900-1600) (rpm) and at the selected compression ratios of (18-23). From the experimental results it is determined that by application of gasoline fumigation effective power output increases at the levels of 4-9%, effective efficiency increases by approximately 1.5-4% and specific fuel consumption decreases by approximately 1.5-4%. It is also determined that 4-6% fumigation ratio range is the most favorable percentage interval of gasoline at the selected compression ratios for this engine. Because cost of gasoline is higher than diesel fuel in Turkey as well as in many of the other countries and the decrease ratio of specific fuel consumption is low, gasoline fumigation is not economic for this engine. In the presented study, heat balance tests have also been performed for 18 and 21 compression ratios. The heat balance has been investigated experimentally in respect of effective power, heat rejected to the cooling water, heat lost through exhaust, and other losses (unaccounted-for losses). Heat lost through exhaust decreases until 4-6% gasoline fumigation ratios and after these fumigation ratios it starts to increase because of increasing exhaust gas temperature. Heat rejected to the cooling water decreases at low fumigation ratios, but at high fumigation ratios it increases. Other losses generally exhibit an increasing tendency at low fumigation ratios

  14. Experimental study on fuel economies and emissions of direct-injection premixed combustion engine fueled with gasoline/diesel blends

    International Nuclear Information System (INIS)

    Du, Jiakun; Sun, Wanchen; Guo, Liang; Xiao, Senlin; Tan, Manzhi; Li, Guoliang; Fan, Luyan

    2015-01-01

    Highlights: • A compound combustion concept was proposed and investigated. • Premixed combustion near the top dead center was investigated using blended fuels. • Increasing gasoline blend ratio was found to enhance the mixture preparation. • Too much addition of gasoline decreases indicated thermal efficiency. • Gasoline/diesel blends may be a promising alternative for premixed combustion. - Abstract: The effects of gasoline/diesel blended fuel composed of diesel fuel with gasoline as additives in volume basis, on combustion, fuel economies and exhaust emissions were experimentally investigated. Tests were carried out based on a turbocharged Common-rail Direct Injection engine at a constant engine speed of 1800 r/min and different loads of 3.2 bar, 5.1 bar Indicated Mean Effective Pressure. Additionally, the effect of combustion phasing and Exhaust Gas Recirculation were evaluated experimentally for various fuels. The results indicated that with the fraction of gasoline increasing in blends, the ignition delay was prolonged and the combustion phasing was retarded with the common injection timing. This led to a significant increase of premixed burning phase, which was in favor of smoke reduction; although, too much gasoline might be adverse to fuel consumption. An optimum combustion phasing was identified, leading to a higher thermal efficiency and better premixed combustion with blended fuels. A combined application of Exhaust Gas Recirculation and blended fuel with a high gasoline fraction was confirmed effective in reducing the oxides of nitrogen and smoke emissions simultaneously at the optimum combustion phasing without giving significant penalty of fuel consumption. A compound combustion mode with its emission lower than the conventional Compression Ignition engines, and efficiency higher than the typical Spark Ignition engines, could be achieved with a cooperative control of Exhaust Gas Recirculation and combustion phasing of the gasoline

  15. Biodiesel production from inedible animal tallow and an experimental investigation of its use as alternative fuel in a direct injection diesel engine

    International Nuclear Information System (INIS)

    Oener, Cengiz; Altun, Sehmus

    2009-01-01

    In this study, a substitute fuel for diesel engines was produced from inedible animal tallow and its usability was investigated as pure biodiesel and its blends with petroleum diesel fuel in a diesel engine. Tallow methyl ester as biodiesel fuel was prepared by base-catalyzed transesterification of the fat with methanol in the presence of NaOH as catalyst. Fuel properties of methyl ester, diesel fuel and blends of them (5%, 20% and 50% by volume) were determined. Viscosity and density of fatty acid methyl ester have been found to meet ASTM D6751 and EN 14214 specifications. Viscosity and density of tallow methyl esters are found to be very close to that of diesel. The calorific value of biodiesel is found to be slightly lower than that of diesel. An experimental study was carried out in order to investigate of its usability as alternative fuel of tallow methyl ester in a direct injection diesel engine. It was observed that the addition of biodiesel to the diesel fuel decreases the effective efficiency of engine and increases the specific fuel consumption. This is due to the lower heating value of biodiesel compared to diesel fuel. However, the effective engine power was comparable by biodiesel compared with diesel fuel. Emissions of carbon monoxide (CO), oxides of nitrogen (NO x ), sulphur dioxide (SO 2 ) and smoke opacity were reduced around 15%, 38.5%, 72.7% and 56.8%, respectively, in case of tallow methyl esters (B100) compared to diesel fuel. Besides, the lowest CO, NO x emissions and the highest exhaust temperature were obtained for B20 among all other fuels. The reductions in exhaust emissions made tallow methyl esters and its blends, especially B20 a suitable alternative fuel for diesel and thus could help in controlling air pollution. Based on this study, animal tallow methyl esters and its blends with petroleum diesel fuel can be used a substitute for diesel in direct injection diesel engines without any engine modification. (author)

  16. Improving the performance of a compression ignition engine by directing flow of inlet air

    Science.gov (United States)

    Kemper, Carlton

    1946-01-01

    The object of this report is to present the results of tests performed by the National Advisory Committee for Aeronautics to determine the effect on engine performance of directing the flow of the inlet air to a 5-inch by 7-inch cylinder, solid injection, compression ignition engine, After a few preliminary tests, comparative runs were made at a speed of 1500 r.p.m. with and without directed air flow. It was found that directing the flow of the inlet air toward the fuel injection valve gave steadier engine operation, and an appreciable increase in power, and decreased fuel consumption. The results indicate the possibility of improving the performance of a given type of combustion chamber without changing its shape and with no change in valve timing. They would also seem to prove that directional turbulence, set up before the inlet valve of a four-stroke cycle engine, continues in the engine cylinder throughout the compression stroke.

  17. Development of High Efficiency and Low Emission Low Temperature Combustion Diesel Engine with Direct EGR Injection

    Science.gov (United States)

    Ho, R. J.; Kumaran, P.; Yusoff, M. Z.

    2016-03-01

    Focus on energy and environmental sustainability policy has put automotive research & development directed to developing high efficiency and low pollutant power train. Diffused flame controlled diesel combustion has reach its limitation and has driven R&D to explore other modes of combustions. Known effective mode of combustion to reduce emission are Low temperature combustion (LTC) and homogeneous charge combustion ignition by suppressing Nitrogen Oxide(NOx) and Particulate Matter (PM) formation. The key control to meet this requirement are chemical composition and distribution of fuel and gas during a combustion process. Most research to accomplish this goal is done by manipulating injected mass flow rate and varying indirect EGR through intake manifold. This research paper shows viable alternative direct combustion control via co-axial direct EGR injection with fuel injection process. A simulation study with OpenFOAM is conducted by varying EGR injection velocity and direct EGR injector diameter performed with under two conditions with non-combustion and combustion. n-heptane (C7H16) is used as surrogate fuel together with 57 species 290 semi-detailed chemical kinetic model developed by Chalmers University is used for combustion simulation. Simulation result indicates viability of co-axial EGR injection as a method for low temperature combustion control.

  18. The new 3.5L V6 gasoline engine adopting the innovative stoichiometric direct injection system D-4S; Der neue 3.5L V6 Benzinmotor mit dem innovativen stoechiometrischen Direkteinspritzsystem D-4S

    Energy Technology Data Exchange (ETDEWEB)

    Tsuji, N.; Sugiyama, M.; Abe, S. [Toyota Motor Corp. (Japan)

    2006-07-01

    A new 3.5L V6 engine was introduced for the new Lexus sedan vehicles, GS350 and IS350 in Japan in August 2005. In 2006, this engine will be adapted to the power source of the new hybrid rear wheel driven vehicle GS450h. This new engine uses a newly developed stoichiometric direct injection system with two fuel injectors in each cylinder (this system is called D-4S: direct injection 4-stroke gasoline engine system superior version). One is a direct injection injector generating a dual-vertical-fan-shaped spray with wide dispersion, while the other is a port injector. This new fuel injection system can maximize the DI advantage for full-load performance. Simultaneously the optimisation of the intake and exhaust system and the increase of stiffness of the moving parts such as the timing chain system and the valve train system enable a specific power of 67kW/L and 234kW at 6400r/min to be achieved, placing it near the top of all naturally aspirated production gasoline engines in the world. Additionally, employing the dual-VVTi system (intake and exhaust VVT system) and the long dual exhaust pipe, an excellent maximum torque of 380Nm at 4800r/min was achieved while keeping 90 percent of maximum torque for a wide engine speed range from 2000r/min to 6500r/min. (orig.)

  19. Influence of injection timing on the exhaust emissions of a dual-fuel CI engine

    Energy Technology Data Exchange (ETDEWEB)

    Sayin, Cenk [Department of Mechanical Education, Marmara University, 34722 Istanbul (Turkey); Uslu, Kadir [Department of Automotive Education, Fatih Vocational High School, 54100 Sakarya (Turkey); Canakci, Mustafa [Department of Mechanical Education, Kocaeli University, 41380 Kocaeli (Turkey); Alternative Fuels R and D Center, Kocaeli University, 41040 Kocaeli (Turkey)

    2008-06-15

    Environmental concerns and limited amount of petroleum fuels have caused interests in the development of alternative fuels for internal combustion (IC) engines. As an alternative, biodegradable, and renewable fuel, ethanol is receiving increasing attention. Therefore, in this study, influence of injection timing on the exhaust emission of a single cylinder, four stroke, direct injection, naturally aspirated diesel engine has been experimentally investigated using ethanol blended diesel fuel from 0% to 15% with an increment of 5%. The engine has an original injection timing 27 CA BTDC. The tests were performed at five different injection timings (21 , 24 , 27 , 30 , and 33 CA BTDC) by changing the thickness of advance shim. The experimental test results showed that NO{sub x} and CO{sub 2} emissions increased as CO and HC emissions decreased with increasing amount of ethanol in the fuel mixture. When compared to the results of original injection timing, at the retarded injection timings (21 and 24 CA BTDC), NO{sub x} and CO{sub 2} emissions increased, and unburned HC and CO emissions decreased for all test conditions. On the other hand, with the advanced injection timings (30 and 33 CA BTDC), HC and CO emissions diminished, and NO{sub x} and CO{sub 2} emissions boosted for all test conditions. (author)

  20. A Comparative Study of Engine Performance and Exhaust Emissions Characteristics of Linseed Oil Biodiesel Blends with Diesel Fuel in a Direct Injection Diesel Engine

    Science.gov (United States)

    Salvi, B. L.; Jindal, S.

    2013-01-01

    This paper is aimed at study of the performance and emissions characteristics of direct injection diesel engine fueled with linseed oil biodiesel blends and diesel fuel. The comparison was done with base fuel as diesel and linseed oil biodiesel blends. The experiments were conducted with various blends of linseed biodiesel at different engine loads. It was found that comparable mass fraction burnt, better rate of pressure rise and BMEP, improved indicated thermal efficiency (8-11 %) and lower specific fuel consumption (3.5-6 %) were obtained with LB10 blend at full load. The emissions of CO, un-burnt hydrocarbon and smoke were less as compared to base fuel, but with slight increase in the emission of NOx. Since, linseed biodiesel is renewable in nature, so practically negligible CO2 is added to the environment. The linseed biodiesel can be one of the renewable alternative fuels for transportation vehicles and blend LB10 is preferable for better efficiency.

  1. Quantitative analysis of the near-wall mixture formation process in a passenger car direct-injection diesel engine by using linear raman spectroscopy.

    Science.gov (United States)

    Taschek, Marco; Egermann, Jan; Schwarz, Sabrina; Leipertz, Alfred

    2005-11-01

    Optimum fuel preparation and mixture formation are core issues in the development of modern direct-injection (DI) Diesel engines, as these are crucial for defining the border conditions for the subsequent combustion and pollutant formation process. The local fuel/air ratio can be seen as one of the key parameters for this optimization process, as it allows the characterization and comparison of the mixture formation quality. For what is the first time to the best of our knowledge, linear Raman spectroscopy is used to detect the fuel/air ratio and its change along a line of a few millimeters directly and nonintrusively inside the combustion bowl of a DI Diesel engine. By a careful optimization of the measurement setup, the weak Raman signals could be separated successfully from disturbing interferences. A simultaneous measurement of the densities of air and fuel was possible along a line of about 10 mm length, allowing a time- and space-resolved measurement of the local fuel/air ratio. This could be performed in a nonreacting atmosphere as well as during fired operating conditions. The positioning of the measurement volume next to the interaction point of one of the spray jets with the wall of the combustion bowl allowed a near-wall analysis of the mixture formation process for a six-hole nozzle under varying injection and engine conditions. The results clearly show the influence of the nozzle geometry and preinjection on the mixing process. In contrast, modulation of the intake air temperature merely led to minor changes of the fuel concentration in the measurement volume.

  2. Comparison of the effect of biodiesel-diesel and ethanol-diesel on the gaseous emission of a direct-injection diesel engine

    Science.gov (United States)

    Di, Yage; Cheung, C. S.; Huang, Zuohua

    Experiments were conducted on a 4-cylinder direct-injection diesel engine using ultralow sulfur diesel blended with biodiesel and ethanol to investigate the gaseous emissions of the engine under five engine loads at the maximum torque engine speed of 1800 rev min -1. Four biodiesel blended fuels and four ethanol blended fuels with oxygen concentrations of 2%, 4%, 6% and 8% were used. With the increase of oxygen content in the blended fuels, the brake thermal efficiency improves slightly. For the diesel-biodiesel fuels, the brake specific HC and CO emissions decrease while the brake specific NO x and NO 2 emissions increase. The emissions of formaldehyde, 1,3-butadiene, toluene, xylene and overall BTX (benzene, toluene, xylene) in general decrease, however, acetaldehyde and benzene emissions increase. For the diesel-ethanol fuels, the brake specific HC and CO emissions increase significantly at low engine load, NO x emission decreases at low engine load but increases at high engine load. The emissions of benzene and BTX vary with engine load and ethanol content. Similar to the biodiesel-diesel fuels, the formaldehyde, 1,3-butadiene, toluene and xylene emissions decrease while the acetaldehyde and NO 2 emissions increase. Despite having the same oxygen contents in the blended fuels, there are significant differences in the gaseous emissions between the biodiesel-diesel blends and the ethanol-diesel blends.

  3. Computational study of the effect of different injection angle on heavy duty diesel engine combustion

    Directory of Open Access Journals (Sweden)

    Ranjbar Ali Akbar

    2009-01-01

    Full Text Available Diesel engines exhausting gaseous emission and particulate matter have long been regarded as one of the major air pollution sources, particularly in metropolitan areas, and have been a source of serious public concern for a long time. The choosing various injection strategies is not only motivated by cost reduction but is also one of the potentially effective techniques to reduce exhaust emission from diesel engines. The purpose of this study is to investigate the effect of different injection angles on a heavy duty diesel engine and emission characteristics. The varieties of injection angle were simulated and the emissions like soot and NO is calculated. The comparison between the different injection strategies was also investigated. A combustion chamber for three injection strategies (injection direction with angles of α=67.5, 70, and 72.5 degree was simulated. The comparative study involving rate of heat release, in-cylinder temperature, in-cylinder pressure, NO and soot emissions were also reported for different injection strategies. The case of α=70 is optimum because in this manner the emissions are lower in almost most of crank angle than two other cases and the in-cylinder pressure, which is a representation of engine power, is higher than in the case of α=67.5 and just a little lower than in the case of α=72.5.

  4. Influence of Compression Ratio on High Load Performance and Knock Behavior for Gasoline Port-Fuel Injection, Natural Gas Direct Injection and Blended Operation in a Spark Ignition Engine

    Energy Technology Data Exchange (ETDEWEB)

    Pamminger, Michael; Sevik, James; Scarcelli, Riccardo; Wallner, Thomas; Hall, Carrie

    2017-03-28

    Natural Gas (NG) is an alternative fuel which has attracted a lot of attention recently, in particular in the US due to shale gas availability. The higher hydrogen-to-carbon (H/C) ratio, compared to gasoline, allows for decreasing carbon dioxide emissions throughout the entire engine map. Furthermore, the high knock resistance of NG allows increasing the efficiency at high engine loads compared to fuels with lower knock resistance. NG direct injection (DI) allows for fuel to be added after intake valve closing (IVC) resulting in an increase in power density compared to an injection before IVC. Steady-state engine tests were performed on a single-cylinder research engine equipped with gasoline (E10) port-fuel injection (PFI) and NG DI to allow for in-cylinder blending of both fuels. Knock investigations were performed at two discrete compression ratios (CR), 10.5 and 12.5. Operating conditions span mid-load, wide-open-throttle and boosted conditions, depending on the knock response of the fuel blend. Blended operation was performed using E10 gasoline and NG. An additional gasoline type fuel (E85) with higher knock resistance than E10 was used as a high-octane reference fuel, since the octane rating of E10-NG fuel blends is unknown. Spark timing was varied at different loads under stoichiometric conditions in order to study the knock response as well as the effects on performance and efficiency. As anticipated, results suggest that the knock resistance can be increased significantly by increasing the NG amount. Comparing the engine operation with the least knock resistant fuel, E10 PFI, and the fuel blend with the highest knock resistance, 75% NG DI, shows an increase in indicated mean effective pressure of about 9 bar at CR 12.5. The usage of reference fuels with known knock characteristics allowed an assessment of knock characteristic of intermediate E10-NG blend levels. Mathematical correlations were developed allowing characterizing the occurrence of knocking

  5. Diesel Combustion and Emission Using High Boost and High Injection Pressure in a Single Cylinder Engine

    Science.gov (United States)

    Aoyagi, Yuzo; Kunishima, Eiji; Asaumi, Yasuo; Aihara, Yoshiaki; Odaka, Matsuo; Goto, Yuichi

    Heavy-duty diesel engines have adopted numerous technologies for clean emissions and low fuel consumption. Some are direct fuel injection combined with high injection pressure and adequate in-cylinder air motion, turbo-intercooler systems, and strong steel pistons. Using these technologies, diesel engines have achieved an extremely low CO2 emission as a prime mover. However, heavy-duty diesel engines with even lower NOx and PM emission levels are anticipated. This study achieved high-boost and lean diesel combustion using a single cylinder engine that provides good engine performance and clean exhaust emission. The experiment was done under conditions of intake air quantity up to five times that of a naturally aspirated (NA) engine and 200MPa injection pressure. The adopted pressure booster is an external supercharger that can control intake air temperature. In this engine, the maximum cylinder pressure was increased and new technologies were adopted, including a monotherm piston for endurance of Pmax =30MPa. Moreover, every engine part is newly designed. As the boost pressure increases, the rate of heat release resembles the injection rate and becomes sharper. The combustion and brake thermal efficiency are improved. This high boost and lean diesel combustion creates little smoke; ISCO and ISTHC without the ISNOx increase. It also yields good thermal efficiency.

  6. Investigation of low emission combustors using hydrogen lean direct injection

    Directory of Open Access Journals (Sweden)

    Robert ISAC

    2011-09-01

    Full Text Available One of the key technology challenges for the use of hydrogen in gas turbine engines is the performance of the combustion system, in particular the fuel injectors. Tests were conducted to measure the nitrogen oxide (NOx emissions and combustion performance at inlet conditions of 588 to 811 K, 0.4 to 1.4 MPa, and equivalence ratios up to 0.48. All the injectors were based on Lean Direct Injection (LDI technology with multiple injection points and quick mixing. One challenge to hydrogen-based premixing combustion systems is flashback since hydrogen has a reaction rate over 7 times that of Jet-A.

  7. Physicochemical characterization of particulate emissions from a compression ignition engine employing two injection technologies and three fuels.

    Science.gov (United States)

    Surawski, N C; Miljevic, B; Ayoko, G A; Roberts, B A; Elbagir, S; Fairfull-Smith, K E; Bottle, S E; Ristovski, Z D

    2011-07-01

    Alternative fuels and injection technologies are a necessary component of particulate emission reduction strategies for compression ignition engines. Consequently, this study undertakes a physicochemical characterization of diesel particulate matter (DPM) for engines equipped with alternative injection technologies (direct injection and common rail) and alternative fuels (ultra low sulfur diesel, a 20% biodiesel blend, and a synthetic diesel). Particle physical properties were addressed by measuring particle number size distributions, and particle chemical properties were addressed by measuring polycyclic aromatic hydrocarbons (PAHs) and reactive oxygen species (ROS). Particle volatility was determined by passing the polydisperse size distribution through a thermodenuder set to 300 °C. The results from this study, conducted over a four point test cycle, showed that both fuel type and injection technology have an impact on particle emissions, but injection technology was the more important factor. Significant particle number emission (54%-84%) reductions were achieved at half load operation (1% increase-43% decrease at full load) with the common rail injection system; however, the particles had a significantly higher PAH fraction (by a factor of 2 to 4) and ROS concentrations (by a factor of 6 to 16) both expressed on a test-cycle averaged basis. The results of this study have significant implications for the health effects of DPM emissions from both direct injection and common rail engines utilizing various alternative fuels.

  8. An injection limiting thrustor control device for internal combustion engines

    International Nuclear Information System (INIS)

    Givaudan, B.

    1993-01-01

    The aim of this device is the automatic limitation, without any command circuit, of the injection in large diesel engines (16 or 20 cylinders) during a compressed air assisted start-up. The thrustor is driven directly by the compressed air. The limitation may be extended and regulated by the means of valves. Application to start-up of diesel generating sets for nuclear power plants

  9. NO-diagnostics in the combustion chamber of a gasoline direct-injection engine with spray-guided combustion process in a four-cylinder transparent engine; NO-Diagnostik im Brennraum eines direkteinspritzenden Ottomotors mit strahlgefuehrtem Brennverfahren an einem Vierzylinder-Transparentmotor

    Energy Technology Data Exchange (ETDEWEB)

    Suck, G.; Jakobs, J. [Volkswagen AG - Konzernforschung, Wolfsburg (Germany); Nicklitzsch, S. [IAV GmbH - Versuch Ottomotoren, Chemnitz (Germany); Bessler, W.G.; Hofmann, M.; Schulz, C. [PCI, Universitaet Heidelberg (Germany)

    2004-07-01

    For further reduction of fuel consumption in modern gasoline direct-injection engines, the Volkswagen Group Research is investigating the spray-guided combustion process. To benefit from fuel economy achieved by this combustion process in the sustained development of the Volkswagen FSI {sup registered} -technology, minimizing the engine-out NO{sub x}-emissions is necessary. In this proceeding, we report on the application of several measurement techniques, which include NO-LIF, in-cylinder gas sampling and fast CLD. The aim is the identification of major factors which effect NO-formation in a spray-guided combustion process. Double-injection during the compression stroke allows the generation of double-stratification of the air-fuel mixture cloud. A fuel-rich core with good ignition characteristics is surrounded by a fuel-lean gas mixture. These conditions show that NO-emissions can significantly be reduced while maintaining the good fuel economy. Spray-guided direct-injection allows the expansion of the operation-map area with stratified operation in comparison to recent serial production gasoline DI engines with wall-guided or air-guided combustion processes. It is, however, only possible to benefit from this advantage under realistic conditions of an operating automobile application when the engine-out NO{sub x}-flux is below a limit given by the storage capacity of the catalyst. NO{sub x} exhaust aftertreatment with storage catalysts requires regeneration cycles with fuel-air equivalent ratios {phi} > 1, which effectively increase fuel consumption. (orig.)

  10. Investigation of the Impact of Fuel Properties on Particulate Number Emission of a Modern Gasoline Direct Injection Engine

    Energy Technology Data Exchange (ETDEWEB)

    McCormick, Robert L [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Fioroni, Gina [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Fatouraie, Mohammad [Robert Bosch LLC; Frommherz, Mario [Robert Bosch LLC; Mosburger, Michael [Robert Bosch LLC; Chapman, Elana [General Motors LLC; Li, Sharon [General Motors LLC

    2018-04-03

    Gasoline Direct Injection (GDI) has become the preferred technology for spark-ignition engines resulting in greater specific power output and lower fuel consumption, and consequently reduction in CO2 emission. However, GDI engines face a substantial challenge in meeting new and future emission limits, especially the stringent particle number (PN) emissions recently introduced in Europe and China. Studies have shown that the fuel used by a vehicle has a significant impact on engine out emissions. In this study, nine fuels with varying chemical composition and physical properties were tested on a modern turbo-charged side-mounted GDI engine with design changes to reduce particulate emissions. The fuels tested included four fuels meeting US certification requirements; two fuels meeting European certification requirements; and one fuel meeting China 6 certification requirements being proposed at the time of this work. Two risk safeguard fuels (RSG), representing the properties of worst case market fuels in Europe and China, were also included. The particle number concentration of the solid particulates was measured in the engine-out exhaust flow at steady state engine operations with load and speed sweeps, and semi-transient load steps. The test results showed a factor of 6 PN emission difference among all certification fuels tested. Combined with detailed fuel analyses, this study evaluated important factors (such as oxygenates, carbon chain length and thermo-physical properties) that cause PN emissions which were not included in PMI index. A linear regression was performed to develop a PN predictive model which showed improved fitting quality than using PMI.

  11. Effect of Hydrogen and Hydrogen Enriched Compressed Natural Gas Induction on the Performance of Rubber Seed Oil Methy Ester Fuelled Common Rail Direct Injection (CRDi Dual Fuel Engines

    Directory of Open Access Journals (Sweden)

    Mallikarjun Bhovi

    2017-06-01

    Full Text Available Renewable fuels are in biodegradable nature and they tender good energy security and foreign exchange savings. In addition they address environmental concerns and socio-economic issues. The present work presents the experimental investigations carried out on the utilization of such renewable fuel combinations for diesel engine applications. For this a single-cylinder four-stroke water cooled direct injection (DI compression ignition (CI engine provided with CMFIS (Conventional Mechanical Fuel Injection System was rightfully converted to operate with CRDi injection systems enabling high pressure injection of Rubber seed oil methyl ester (RuOME in the dual fuel mode with induction of varied gas flow rates of hydrogen and hydrogen enriched CNG (HCNG gas combinations. Experimental investigations showed a considerable improvement in dual fuel engine performance with acceptable brake thermal efficiency and reduced emissions of smoke, hydrocarbon (HC, carbon monoxide (CO and slightly increased nitric oxide (NOx emission levels for increased hydrogen and HCNG flow rates. Further CRDi facilitated dual fuel engine showed improved engine performance compared to CMFIS as the former enabled high pressure (900 bar injection of the RuOME and closer to TDC (Top Dead Centre as well. Combustion parameters such as ignition delay, combustion duration, pressure-crank angle and heat release rates were analyzed and compared with baseline data generated. Combustion analysis showed that the rapid rate of burning of hydrogen and HCNG along with air mixtures increased due to presence of hydrogen in total and in partial combination with CNG which further resulted into higher cylinder pressures and energy release rates. However, sustained research that can provide feasible engine technology operating on such fuels in dual fuel operation can pave the way for continued fossil fuel usage.

  12. Effect of fuel injection timing and intake pressure on the performance of a DI diesel engine - A parametric study using CFD

    International Nuclear Information System (INIS)

    Jayashankara, B.; Ganesan, V.

    2010-01-01

    This paper presents the computational fluid dynamics (CFD) modeling to study the effect of fuel injection timing and intake pressure (naturally aspirated as well as supercharged condition) on the performance of a direct injection (DI) diesel engine. The performance characteristics of the engine are investigated under transient conditions. A single cylinder direct injection diesel engine with two directed intake ports whose outlet is tangential to the wall of the cylinder and two exhaust ports has been taken up for the study. Effect of injection timing (start of injection 16, 12 and 8 CAD bTDC) and intake pressure (1.01, 1.21 and 1.71 bar) on the performance of the engine has been investigated for an engine speed of 1000 rpm. CFD predicted results during both suction and compression strokes under motoring conditions have been validated with experimental results available in the literature. Magnusson's eddy break-up model is used for combustion simulation. Predicted performance and emission characteristics such as pressure, temperature, heat release, NO x , and soot are presented and discussed. The predicted values reveal that retarding the injection timing results in increase in-cylinder pressure, temperature, heat release rate, cumulative heat release and NO x emissions. Decreasing trend is observed by advancing the injection timing. In case of soot emission the increasing trend is observed up to certain crank angle then reverse trend is seen. The supercharged with inter-cooled cases show lower peak heat release rate and maximum cumulative heat release, shorter ignition delay, higher NO x and lower soot emissions.

  13. Investigation of the effects of steam injection on performance and NO emissions of a diesel engine running with ethanol–diesel blend

    International Nuclear Information System (INIS)

    Gonca, Guven

    2014-01-01

    Highlights: • A combustion simulation is conducted by using two-zone combustion model. • Effect of steam injection into engine fueled ethanol–diesel blend are investigated. • It is shown that this method improves performance and diminish NO emissions. - Abstract: The use of ethanol–diesel blends in diesel engines without any modifications negatively affects the engine performance and NOx emissions. However, steam injection method decreases NOx emissions and improves the engine performance. In this study, steam injection method is applied into a single cylinder, four-stroke, direct injection, naturally aspirated diesel engine fueled with ethanol–diesel blend in order improve the performance and NOx emissions by using two-zone combustion model for 15% ethanol addition and 20% steam ratios at full load condition. The results obtained are compared with conventional diesel engine (D), steam injected diesel engine (D + S20), diesel engine fueled with ethanol–diesel blend (E15) and steam injected diesel engine fueled with ethanol–diesel blend (E15 + S20) in terms of performance and NO emissions. The results showed that as NO emissions considerably decrease the performance significantly increases with steam injection method

  14. Influence of injection timing on DI diesel engine characteristics fueled with waste transformer oil

    Directory of Open Access Journals (Sweden)

    S. Prasanna Raj Yadav

    2015-12-01

    Full Text Available This research work targets on the effective utilization of WTO (waste transformer oil in a diesel engine, which would rather reduce environmental problems caused by disposing of it in the open land. The waste transformer oil was compared with the conventional diesel fuel and found that it can also be used as fuel in compression ignition engines since the WTO is also a derivative of crude oil. In this present work, the WTO has been subjected to traditional base-catalyzed trans-esterification process in order to reduce the high viscosity of the WTO which helps to effectively utilize WTO as a fuel in DI diesel engine. The objective of the work is to study the influence of injection timing on the performance, emission and combustion characteristics of a single cylinder, four stroke, direct injection diesel engine using TWTO (trans-esterified waste transformer oil as a fuel. Experiments were performed at four injection timings (23°, 22°, 21°, and 20° bTDC. The results indicate that the retarded injection timing of 20° bTDC resulted in decreased oxides of nitrogen, carbon monoxide and unburned hydrocarbon by 11.57%, 17.24%, and 10% respectively while the brake thermal efficiency and smoke increased under all the load conditions when compared to that of standard injection timing.

  15. Theoretical investigation of heat balance in direct injection (DI) diesel engines for neat diesel fuel and gasoline fumigation

    International Nuclear Information System (INIS)

    Durgun, O.; Sahin, Z.

    2009-01-01

    The main purpose of the presented study is to evaluate energy balance theoretically in direct injection (DI) diesel engines at different conditions. To analyze energy balance, a zero-dimensional multi-zone thermodynamic model has been developed and used. In this thermodynamic model, zero-dimensional intake and exhaust approximations given by Durgun, zero-dimensional compression and expansion model given by Heywood and quasi-dimensional phenomenological combustion model developed by Shahed and then improved Ottikkutti have been used and developed with new approximations and assumptions. By using the developed model, complete diesel engine cycle, engine performance parameters and exhaust emissions can be determined easily. Also, by using this model energy balance can be analyzed for neat diesel fuel and for light fuel fumigation easily. In the presented study, heat balance has been investigated theoretically for three different engines and various numerical applications have been conducted. In the numerical applications two different turbocharged DI diesel engines and a naturally aspirated DI diesel engine have been used. From these numerical applications, it is determined that, what portion of available fuel energy is converted to useful work, what amount of fuel energy is lost by exhaust gases or lost by heat transfer. In addition, heat balance has been analyzed for gasoline fumigation and some numerical results have been given. Brake effective power and brake specific fuel consumption increase and brake effective efficiency decreases for gasoline fumigation for turbocharged diesel engines used in numerical applications. Combustion duration increases with increasing fumigation ratio and thus heat transfer to the walls increases. Because exhaust temperature increases, exhaust losses also increases for fumigation case

  16. Comparison of Airway Responses Induced in a Mouse Model by the Gas and Particulate Fractions of Gasoline Direct Injection Engine Exhaust

    Directory of Open Access Journals (Sweden)

    Caitlin L. Maikawa

    2018-03-01

    Full Text Available Diesel exhaust has been associated with asthma, but its response to other engine emissions is not clear. The increasing prevalence of vehicles with gasoline direct injection (GDI engines motivated this study, and the objective was to evaluate pulmonary responses induced by acute exposure to GDI engine exhaust in an allergic asthma murine model. Mice were sensitized with an allergen to induce airway hyperresponsiveness or treated with saline (non-allergic group. Animals were challenged for 2-h to exhaust from a laboratory GDI engine operated at conditions equivalent to a highway cruise. Exhaust was filtered to assess responses induced by the particulate and gas fractions. Short-term exposure to particulate matter from GDI engine exhaust induced upregulation of genes related to polycyclic aromatic hydrocarbon (PAH metabolism (Cyp1b1 and inflammation (TNFα in the lungs of non-allergic mice. High molecular weight PAHs dominated the particulate fraction of the exhaust, and this response was therefore likely attributable to the presence of these PAHs. The particle fraction of GDI engine exhaust further contributed to enhanced methacholine responsiveness in the central and peripheral tissues in animals with airway hyperresponsiveness. As GDI engines gain prevalence in the vehicle fleet, understanding the health impacts of their emissions becomes increasingly important.

  17. Comparison of Airway Responses Induced in a Mouse Model by the Gas and Particulate Fractions of Gasoline Direct Injection Engine Exhaust.

    Science.gov (United States)

    Maikawa, Caitlin L; Zimmerman, Naomi; Ramos, Manuel; Shah, Mittal; Wallace, James S; Pollitt, Krystal J Godri

    2018-03-01

    Diesel exhaust has been associated with asthma, but its response to other engine emissions is not clear. The increasing prevalence of vehicles with gasoline direct injection (GDI) engines motivated this study, and the objective was to evaluate pulmonary responses induced by acute exposure to GDI engine exhaust in an allergic asthma murine model. Mice were sensitized with an allergen to induce airway hyperresponsiveness or treated with saline (non-allergic group). Animals were challenged for 2-h to exhaust from a laboratory GDI engine operated at conditions equivalent to a highway cruise. Exhaust was filtered to assess responses induced by the particulate and gas fractions. Short-term exposure to particulate matter from GDI engine exhaust induced upregulation of genes related to polycyclic aromatic hydrocarbon (PAH) metabolism ( Cyp1b1 ) and inflammation ( TNFα ) in the lungs of non-allergic mice. High molecular weight PAHs dominated the particulate fraction of the exhaust, and this response was therefore likely attributable to the presence of these PAHs. The particle fraction of GDI engine exhaust further contributed to enhanced methacholine responsiveness in the central and peripheral tissues in animals with airway hyperresponsiveness. As GDI engines gain prevalence in the vehicle fleet, understanding the health impacts of their emissions becomes increasingly important.

  18. A Comparative Study on Energy and Exergy Analyses of a CI Engine Performed with Different Multiple Injection Strategies at Part Load: Effect of Injection Pressure

    Directory of Open Access Journals (Sweden)

    Muammer Özkan

    2015-01-01

    Full Text Available In this study, a four stroke four cylinder direct injection CI engine was run using three different injection pressures. In all measurements, the fuel quantity per cycle, the pre injection and main injection timing, the boost pressure and the engine speed were kept constant. The motor tests were performed under 130, 140 and 150 MPa rail pressure. During the theoretical part of the study, combustion, emission, energy and exergy analysis were made using the test results. An increase in the injection pressure increases combustion efficiency. The results show that combustion efficiency is not enough by itself, because the increase in the power need of the injection pump, decreases the thermal efficiency. The increase in the combustion temperature, increases the cooling loss and decreases the exergetic efficiency. In addition, the NOx emissions increased by 12% and soot emissions decreased 44% via increasing injection pressure by 17%. The thermal and exergetic efficiencies are found inversely proportional with injection pressure. Exergy destruction is found independent of the injection pressure and its value is obtained as ~6%.

  19. Effect of injection timing on the exhaust emissions of a diesel engine using diesel-methanol blends

    Energy Technology Data Exchange (ETDEWEB)

    Sayin, Cenk; Gumus, Metin [Department of Mechanical Education, Marmara University, 34722 Istanbul (Turkey); Ilhan, Murat [Raytheon Training International GmbH, GM Academy, 34843 Istanbul (Turkey); Canakci, Mustafa [Department of Mechanical Education, Kocaeli University, 41380 Kocaeli (Turkey)]|[Alternative Fuels R and D Center, Kocaeli University, 41040 Kocaeli (Turkey)

    2009-05-15

    Environmental concerns and limited resource of petroleum fuels have caused interests in the development of alternative fuels for internal combustion (IC) engines. For diesel engines, alcohols are receiving increasing attention because they are oxygenated and renewable fuels. Therefore, in this study, the effect of injection timing on the exhaust emissions of a single cylinder, naturally aspirated, four-stroke, direct injection diesel engine has been experimentally investigated by using methanol-blended diesel fuel from 0% to 15% with an increment of 5%. The tests were conducted for three different injection timings (15 , 20 and 25 CA BTDC) at four different engine loads (5 Nm, 10 Nm, 15 Nm, 20 Nm) at 2200 rpm. The experimental test results showed that Bsfc, NO{sub x} and CO{sub 2} emissions increased as BTE, smoke opacity, CO and UHC emissions decreased with increasing amount of methanol in the fuel mixture. When compared the results to those of original injection timing, NO{sub x} and CO{sub 2} emissions decreased, smoke opacity, UHC and CO emissions increased for the retarded injection timing (15 CA BTDC). On the other hand, with the advanced injection timing (25 CA BTDC), decreasing smoke opacity, UHC and CO emissions diminished, and NO{sub x} and CO{sub 2} emissions boosted at all test conditions. In terms of Bsfc and BTE, retarded and advanced injection timings gave negative results for all fuel blends in all engine loads. (author)

  20. Effects of fuel and air mixing on WOT output in direct injection gasoline engine; Chokufun gasoline kikan ni okeru nenryo to kuki no kongo to shutsuryoku seino

    Energy Technology Data Exchange (ETDEWEB)

    Noda, T; Iriya, Y; Naito, K; Mitsumoto, H; Iiyama, A [Nissan Motor Co. Ltd., Tokyo (Japan)

    1997-10-01

    The effects of in-cylinder charge motion and the characteristics of the fuel spray and piston crown shape on WOT output in a direct injection gasoline engine are investigated. The fuel and air mixing process in a cylinder is analyzed by computer simulation and LIF method visualization. As a result, the technical factors to achieve enough mixing in a DI gasoline engine equipped with bowl in piston optimized for stratified combustion are clarified. 7 refs., 9 figs., 1 tab.

  1. The new Mercedes-Benz V8 petrol engine with direct injection and turbocharging; Der neue V8-Ottomotor mit Direkteinspritzung und Turboaufladung von Mercedes-Benz

    Energy Technology Data Exchange (ETDEWEB)

    Doll, Gerhard; Lueckert, Peter; Weckenmann, Hartmut; Kemmler, Roland; Waltner, Anton; Herwig, Helmut [Daimler AG, Stuttgart (Germany)

    2010-07-01

    The new Mercedes-Benz 4,6l bi-turbo engine M 278 was generated as a member of a new high performed engine family of v6 and v8-engines, replacing the very successful 5.5l predecessor engine M 273. This engine is part of a modular conception and offers an exclusive driving performance as well as a fuel economy that up to now was more typical for 6-cylinder engines. It is based on a high-graded technology portfolio that contains direct injection of the 3rd generation, the Mercedes-Benz start-stop-system. heat management and pressure-controlled oil circulation as fundamental devices. Compared with the even today very successful predecessor, power was increased by 12%, torque by 32% and the fuel consumption was reduced by more than 10%. The sustainability of this engine is ensured because of the modular concept. (orig.)

  2. A numerical study of the effects of injection rate shape on combustion and emission of diesel engines

    Directory of Open Access Journals (Sweden)

    He Zhixia

    2014-01-01

    Full Text Available The spray characteristics including spray droplet sizes, droplet distribution, spray tip penetration length and spray diffusion angle directly affects the mixture process of fuel and oxygen and then plays an important role for the improvement of combustion and emission performance of diesel engines. Different injection rate shapes may induce different spray characteristics and then further affect the subsequent combustion and emission performance of diesel engines. In this paper, the spray and combustion processes based on four different injection rate shapes with constant injection duration and injected fuel mass were simulated in the software of AVL FIRE. The numerical models were validated through comparing the results from the simulation with those from experiment. It was found that the dynamic of diesel engines with the new proposed hump shape of injection rate and the original saddle shape is better than that with the injection rate of rectangle and triangle shape, but the emission of NOX is higher. And the soot emission is lowest during the late injection period for the new hump-shape injection rate because of a higher oxidation rate with a better mixture between fuel and air under the high injection pressure.

  3. BMW V8 gasoline engine with turbocharging, direct injection and fully variable valve gear; V8-Ottomotor von BMW mit zwei Turboladern, Direkteinspritzung und vollvariablem Ventiltrieb

    Energy Technology Data Exchange (ETDEWEB)

    Schopp, Johann; Duengen, Rainer; Fach, Heiko [BMW Group, Muenchen (Germany); Schuenemann, Erik

    2013-01-15

    In July 2012, BMW has launched its new V8 gasoline engine with so-called TwinPower Turbo technology, including turbocharging, direct injection and fully variable valve gear Valvetronic. The main objectives were to achieve a significant reduction in fuel consumption and a moderate increase in power output, to derive a 4.0-l engine-capacity version, as well as to ensure high process commonality with the new BMW M5 engine simultaneously developed by BMW M GmbH which uses a virtually identical basic engine. It was first deployed simultaneously in the new 6 Series Gran Coupe, the 5 Series Gran Turismo, the 6 Series and the revised 7 Series. (orig.)

  4. A novel transient wall heat transfer approach for the start-up of SI engines with gasoline direct injection

    Science.gov (United States)

    Lejsek, David; Kulzer, André; Hammer, Jürgen

    2010-11-01

    The introduction of CO2-reduction technologies like Start-Stop or the Hybrid-Powertrain and the worldwide stringent emission legislation require a detailed optimization of the engine start-up. The combustion concept development as well as the calibration of the engine control unit makes an explicit thermodynamic analysis of the combustion process during the start-up necessary. Initially, the well-known thermodynamic analysis of in-cylinder pressure at stationary condition was transmitted to the highly non-stationary engine start-up. For this running mode of the engine the current models for calculation of the transient wall heat fluxes were found to be misleading. With a fraction of nearly 45% of the burned fuel energy, the wall heat is very important for the calculation of energy balance and for the combustion process analysis. Based on the measurements of transient wall heat transfer densities during the start-up presented in a former work (Lejsek and Kulzer in Investigations on the transient wall heat transfer at start-up for SI engines with gasoline direct injection. SAE Paper), the paper describes the development of adaptations to the known correlations by Woschni (MTZ 31:491, 1970), Hohenberg (Experimentelle Erfassung der Wandwärme von Kolbenmotoren. TU Graz, Habil., 1980) and Bargende (Ein Gleichungsansatz zur Berechnung der instationären Wandwärmeverluste im Hochdruckteil von Ottomotoren. TH Darmstadt, PhD-Thesis, 1991) for the application during engine start-up. To demonstrate the high accuracy of the model, the results of the cyclic resolved thermodynamic analysis using the presented novel approaches were compared with the results of the measurements. It is shown, that the novel heat flux models for the engine start-up process gives a cyclic resolved thermodynamic analysis to optimize the engine start-up pretty efficient.

  5. Injection and Combustion of RME with Water Emulsions in a Diesel Engine

    Directory of Open Access Journals (Sweden)

    J. Cisek

    2010-01-01

    Full Text Available This paper presents ways of using the fully-digitised triggerable AVL VideoScope 513D video system for analysing the injection and combustion inside a diesel engine cylinder fuelled by RME with water emulsions.The research objects were: standard diesel fuel, rapeseed methyl ester (RME and RME – water emulsions. With the aid of a helical flow reactor, stable emulsions with the water fraction up to 30 % weight were obtained, using an additive to prevent the water from separating out of the emulsion.An investigation was made of the effect of the emulsions on exhaust gas emissions (NOX, CO and HC, particulate matter emissions, smoke and the fuel consumption of a one-cylinder HD diesel engine with direct injection. Additionally, the maximum cylinder pressure rise was calculated from the indicator diagram. The test engine was operated at a constant speed of 1 600 rpm and 4 bar BMEP load conditions. The fuel injection and combustion processes were observed and analysed using endoscopes and a digital camera. The temperature distribution in the combustion chamber was analysed quantitatively using the two-colour method. The injection and combustion phenomena were described and compared.A way to reduce NOX formation in the combustion chamber of diesel engines by adding water in the combustion zone was presented. Evaporating water efficiently lowers the peak flame temperature and the temperature in the post-flame zone. For diesel engines, there is an exponential relationship between NOX emissions and peak combustion temperatures. The energy needed to vaporize the water results in lower peak temperatures of the combusted gases, with a consequent reduction in nitrogen oxide formation. The experimental results show up to 50 % NOX emission reduction with the use of 30% water in an RME emulsion, with unchanged engine performance.

  6. On Cyclic Variability in a Residual Effected HCCI Engine with Direct Gasoline Injection during Negative Valve Overlap

    Directory of Open Access Journals (Sweden)

    Jacek Hunicz

    2014-01-01

    Full Text Available This study contributes towards describing the nature of cycle-by-cycle variability in homogeneous charge compression ignition (HCCI engines. Experimental measurements were performed using a single cylinder research engine operated in the negative valve overlap (NVO mode and fuelled with direct gasoline injection. Both stoichiometric and lean mixtures were applied in order to distinguish between different exhaust-fuel reactions during the NVO period and their propagation into the main event combustion. The experimental results show that the mode of cycle-by-cycle variability depends on the NVO phenomena. Under stoichiometric mixture conditions, neither variability in the main event indicated mean effective pressure (IMEP nor the combustion timing was affected by the NVO phenomena; however, long period oscillations in IMEP were observed. In contrast, for lean mixture, where fuel oxidation during the NVO period took place, distinctive correlations between NVO phenomena and the main event combustion parameters were observed. A wavelet analysis revealed the presence of both long-term and short-term oscillations in IMEP, in accordance with the extent of NVO phenomena. Characteristic patterns in IMEP were recognized using an in-house algorithm.

  7. PERFORMANCE AND EMISSION STUDIES ON DI-DIESEL ENGINE FUELED WITH PONGAMIA METHYL ESTER INJECTION AND METHANOL CARBURETION

    Directory of Open Access Journals (Sweden)

    HARIBABU, N.

    2010-03-01

    Full Text Available The target of the present study is to clarify ignition characteristics, combustion process and knock limit of methanol premixture in a dual fuel diesel engine, and also to improve the trade-off between NOx and smoke markedly without deteriorating the high engine performance. Experiment was conducted to evaluate the performance and emission characteristics of direct injection diesel engine operating in duel fuel mode using Pongamia methyl ester injection and methanol carburetion. Methanol is introduced into the engine at different throttle openings along with intake air stream by a carburetor which is arranged at bifurcated air inlet. Pongamia methyl ester fuel was supplied to the engine by conventional fuel injection. The experimental results show that exhaust gas temperatures are moderate and there is better reduction of NOx, HC, CO and CO2 at methanol mass flow rate of 16.2 mg/s. Smoke level was observed to be low and comparable. Improved thermal efficiency of the engine was observed.

  8. Emission, efficiency, and influence in a diesel n-butanol dual-injection engine

    International Nuclear Information System (INIS)

    Zhu, Yanchun; Chen, Zheng; Liu, Jingping

    2014-01-01

    Highlights: • Dual-injection combustion for diesel n-butanol dual-fuel is investigated. • Higher EGR rate results in lower NOx and ITE, but higher smoke, HC and CO. • Larger butanol fraction results in lower smoke and ITE, but higher NOx, HC and CO. • Advanced injection can decrease smoke, HC and CO, and increase ITE. • Coupling of butanol fraction, EGR and injection timing makes for a better performance. - Abstract: In this work, a dual-injection combustion mode for diesel n-butanol dual-fuel, combined direct injection (DI) of diesel with port fuel injection (PFI) of n-butanol, was introduced. Effects of n-butanol fraction, EGR rate and injection timing on this mode were studied on a modified single-cylinder diesel engine at the speed of 1400 r/min and the IMEP of 1.0 MPa. The results indicate that with increased EGR rate, NOx emissions reduce, but smoke emissions increase. As n-butanol fraction is increased, smoke emissions decrease with a small increase in NOx. However, higher HC and CO emissions, higher indicated specific fuel consumption (ISFC) and lower indicated thermal efficiency (ITE) have to be paid with increased n-butanol fraction, especially at high EGR condition. Advancing diesel injection timing suitably has the capacity of mitigating those costs and further decreasing smoke emissions with a small penalty in NOx emissions. Coupling of large butanol fraction, high EGR rate, and advanced injection suitably contributes to a better balance between emissions and efficiency in the diesel n-butanol dual-injection engine

  9. Transformation of a car diesel engine with direct injection and common rail into a dual fuel engine; Trasformazione di un motore automobilistico diesel ad iniezione diretta dotato di common rail in un motore dual fuel

    Energy Technology Data Exchange (ETDEWEB)

    De Risi, A.; Laforgia, D. [Lecce Univ. (Italy). Dipt. di Scienza dei Materiali

    1999-08-01

    The reduced polluting emissions make natural gas a quite interesting alternative fuel for automotive applications. Therefore a car diesel engine has been transformed into a dual fuel engine with pilot injection via the common rail injection system used to ignite the methane-air charge. Standard injection pumps show a certain instability at low flow rates and high engine speed. On the opposite the new common rail system allows to ignite the fuel in all conditions with an amount of gas oil less than 8% of the entire energy required by the engine was enough to ignite the fuel. Furthermore, a power increase has been obtained, with an overall efficiency equal to or even higher than a conventional engine. The article deals with a series of test carried out on 1929 cm{sup 3} direct injection turbo-charged engine and presents the preliminary results. [Italian] La riduzione delle emissioni inquinanti rende il metano un combustibile alternativo piuttosto interessante per applicazioni automobilistiche. Per quasta ragione e' stata realizzata la trasformazione di un motore automobilitico diesel ad iniezione diretta in un motore dual fuel con iniezione pilota prodotta da un sistema common rail. L'adozione del sistema common rail consente l'accensione in ogni condizione con una quantita' di combustibile inferiore all'8% dell'intera energia richiesta alla potenza nominale del motore risolvendo i problemi di instabilita' che una pompa normale presenta a basse portate e ad alta velocita'. In alcuni casi e' stato sufficiente il 3% dell'energia totale richiesta dal motore per accendere la carica. Inoltre si e' ottenuto un aumento della potenza con un'efficienza globale analoga a qualla del motore tradizionale o addirittura migliore. Si riportano i risultati di una campagna di prove condotta su un motore sovralimentato ad iniezione diretta (1929 cm{sup 3}).

  10. Fuel injection apparatus for internal combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Fujisawa, H; Kobayashi, H; Nagata, S

    1975-01-07

    A fuel injection apparatus for a rapid cut of fuel supply to internal combustion engines during deceleration is described. The fuel cut is achieved by an electromagnetic switch. The number of engine revolutions are determined by the movement of cam shafts, and one of the cam shafts is made of electroconductive and nonconductive materials which generate an intermittent electrical signal to the magnetic switch. The device can cut the fuel in any deceleration condition, therefore it is more advantageous than fuel injection utilizing the intake load variation which can operate only under certain deceleration conditions.

  11. Advanced Gasoline Turbocharged Direction Injection (GTDI) Engine Development

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, Terrance [Ford Motor Co., Dearborn, MI (United States)

    2015-12-31

    This program was undertaken in response to US Department of Energy Solicitation DE-FOA-0000079, resulting in a cooperative agreement with Ford and MTU to demonstrate improvement of fuel efficiency in a vehicle equipped with an advanced GTDI engine. Ford Motor Company has invested significantly in GTDI engine technology as a cost effective, high volume, fuel economy solution, marketed globally as EcoBoost technology. Ford envisions additional fuel economy improvement in the medium and long term by further advancing EcoBoost technology. The approach for the project was to engineer a comprehensive suite of gasoline engine systems technologies to achieve the project objectives, and to progressively demonstrate the objectives via concept analysis / computer modeling, single-cylinder and multi-cylinder engine testing on engine dynamometer, and vehicle level testing on chassis rolls.

  12. 3-D simulation of soot formation in a direct-injection diesel engine based on a comprehensive chemical mechanism and method of moments

    Science.gov (United States)

    Zhong, Bei-Jing; Dang, Shuai; Song, Ya-Na; Gong, Jing-Song

    2012-02-01

    Here, we propose both a comprehensive chemical mechanism and a reduced mechanism for a three-dimensional combustion simulation, describing the formation of polycyclic aromatic hydrocarbons (PAHs), in a direct-injection diesel engine. A soot model based on the reduced mechanism and a method of moments is also presented. The turbulent diffusion flame and PAH formation in the diesel engine were modelled using the reduced mechanism based on the detailed mechanism using a fixed wall temperature as a boundary condition. The spatial distribution of PAH concentrations and the characteristic parameters for soot formation in the engine cylinder were obtained by coupling a detailed chemical kinetic model with the three-dimensional computational fluid dynamic (CFD) model. Comparison of the simulated results with limited experimental data shows that the chemical mechanisms and soot model are realistic and correctly describe the basic physics of diesel combustion but require further development to improve their accuracy.

  13. Experimental and theoretical study on spray behaviors of modified bio-ethanol fuel employing direct injection system

    Directory of Open Access Journals (Sweden)

    Ghahremani Amirreza

    2017-01-01

    Full Text Available One of the key solutions to improve engine performance and reduce exhaust emissions of internal combustion engines is direct injection of bio-fuels. A new modified bio-ethanol is produced to be substituted by fossil fuels in gasoline direct injection engines. The key advantages of modified bio-ethanol fuel as an alternative fuel are higher octane number and oxygen content, a long-chain hydro-carbon fuel, and lower emissions compared to fossil fuels. In the present study spray properties of a modified bio-ethanol and its atomization behaviors have been studied experimentally and theoretically. Based on atomization physics of droplets dimensional analysis has been performed to develop a new non-dimensional number namely atomization index. This number determines the atomization level of the spray. Applying quasi-steady jet theory, air entrainment and fuel-air mixing studies have been performed. The spray atomization behaviors such as atomization index number, Ohnesorge number, and Sauter mean diameter have been investigated employing atomization model. The influences of injection and ambient conditions on spray properties of different blends of modified bio-ethanol and gasoline fuels have been investigated performing high-speed visualization technique. Results indicate that decreasing the difference of injection and ambient pressures increases spray cone angle and projected area, and decreases spray tip penetration length. As expected, increasing injection pressure improves atomization behaviors of the spray. Increasing percentage of modified bio-ethanol in the blend, increases spray tip penetration and decreases the projected area as well.

  14. An experimental study of fuel injection strategies in CAI gasoline engine

    Energy Technology Data Exchange (ETDEWEB)

    Hunicz, J.; Kordos, P. [Department of Combustion Engines and Transport, Lublin University of Technology, Nadbystrzycka 36, 20-618 Lublin (Poland)

    2011-01-15

    Combustion of gasoline in a direct injection controlled auto-ignition (CAI) single-cylinder research engine was studied. CAI operation was achieved with the use of the negative valve overlap (NVO) technique and internal exhaust gas re-circulation (EGR). Experiments were performed at single injection and split injection, where some amount of fuel was injected close to top dead centre (TDC) during NVO interval, and the second injection was applied with variable timing. Additionally, combustion at variable fuel-rail pressure was examined. Investigation showed that at fuel injection into recompressed exhaust fuel reforming took place. This process was identified via an analysis of the exhaust-fuel mixture composition after NVO interval. It was found that at single fuel injection in NVO phase, its advance determined the heat release rate and auto-ignition timing, and had a strong influence on NO{sub X} emission. However, a delay of single injection to intake stroke resulted in deterioration of cycle-to-cycle variability. Application of split injection showed benefits of this strategy versus single injection. Examinations of different fuel mass split ratios and variable second injection timing resulted in further optimisation of mixture formation. At equal share of the fuel mass injected in the first injection during NVO and in the second injection at the beginning of compression, the lowest emission level and cyclic variability improvement were observed. (author)

  15. Combustion and emission characteristics of a diesel engine with DME as port premixing fuel under different injection timing

    International Nuclear Information System (INIS)

    Wang, Ying; Zhao, Yuwei; Xiao, Fan; Li, Dongchang

    2014-01-01

    Highlights: • Combustion and emission of diesel engine with DME as premixing fuel were examined. • Injection timing has profound effect on HRR of diffusive combustion in PCCI engine. • DME introduction drastically influenced HRR of PCCI combustion, especially for HTR. • Effect of injection timing on emission of PCCI engine is similar to that of DICI engine. - Abstract: This work dealt with the combustion and exhaust performance of a DME premixed charge compression ignition diesel engine. With the port premixing DME, the heat-release process was made up of the premixed charge homogeneous charge compression ignition combustion and diffusion combustion. The in-cylinder fuel injection timing and port premixing DME quantity played the important roles in combustion and emission control. They had little impact on the peak position of heat-release rate (HRR) during LTR phase. However, they had great effects on the peak values and the crank-angle positions corresponding to the HRR peaks during HTR and diffusion combustion phase. The peak value of HRR increased and the crank-angle corresponding to the HRR peak advanced with an incremental DME quantity or an early injection during HTR phase. However, the peak value of HRR dropped with an incremental DME quantity or a late injection during the diffusion combustion phase. p max and T max increased with an incremental DME quantity or an early injection. At the fixed direct-injection timing, BSFC decreased slightly with a rise of DME quantity due to CA50 closer to TDC. At a fixed DME quantity, BSFC was lowest when diesel was injected into cylinder at 7°CA BTDC. Moreover, as more DME was aspirated from port, NO x emissions decreased firstly but this decreasing trend ceased later. Smoke reduced, but CO and HC increased with a rise of DME quantity. Meanwhile, like the conventional DICI operation, NO x increased, but smoke, CO and HC declined with an early direct-injection

  16. Experiments on Plume Spreading by Engineered Injection and Extraction

    Science.gov (United States)

    Mays, D. C.; Jones, M.; Tigera, R. G.; Neupauer, R.

    2014-12-01

    The notion that groundwater remediation is transport-limited emphasizes the coupling between physical (i.e., hydrodynamic), geochemical, and microbiological processes in the subsurface. Here we leverage this coupling to promote groundwater remediation using the approach of engineered injection and extraction. In this approach, inspired by the literature on chaotic advection, uncontaminated groundwater is injected and extracted through a manifold of wells surrounding the contaminated plume. The potential of this approach lies in its ability to actively manipulate the velocity field near the contaminated plume, generating plume spreading above and beyond that resulting from aquifer heterogeneity. Plume spreading, in turn, promotes mixing and reaction by chemical and biological processes. Simulations have predicted that engineered injection and extraction generates (1) chaotic advection whose characteristics depend on aquifer heterogeneity, and (2) faster rates and increased extent of groundwater remediation. This presentation focuses on a complimentary effort to experimentally demonstrate these predictions experimentally. In preparation for future work using refractive index matched (RIM) porous media, the experiments reported here use a Hele-Shaw apparatus containing silicone oil. Engineered injection and extraction is used to manipulate the geometry of an initially circular plume of black pigment, and photographs record the plume geometry after each step of injection of extraction. Image analysis, using complimentary Eulerian and Lagrangian approaches, reveals the thickness and variability of the dispersion zone surrounding the deformed plume of black pigment. The size, shape, and evolution of this dispersion zone provides insight into the interplay between engineered injection and extraction, which generates plume structure, and dispersion (here Taylor dispersion), which destroys plume structure. These experiments lay the groundwork for application of engineered

  17. Exhaust gas heat recovery through secondary expansion cylinder and water injection in an internal combustion engine

    Directory of Open Access Journals (Sweden)

    Nassiri Toosi Ali

    2017-01-01

    Full Text Available To enhance thermal efficiency and increase performance of an internal combustion engine, a novel concept of coupling a conventional engine with a secondary 4-stroke cylinder and direct water injection process is proposed. The burned gases after working in a traditional 4-stroke combustion cylinder are transferred to a secondary cylinder and expanded even more. After re-compression of the exhaust gases, pre-heated water is injected at top dead center. The evaporation of injected water not only recovers heat from exhaust gases, but also increases the mass of working gas inside the cylinder, therefore improves the overall thermal efficiency. A 0-D/1-D model is used to numerically simulate the idea. The simulations outputs showed that the bottoming cycle will be more efficient at higher engines speeds, specifically in a supercharged/turbocharged engine, which have higher exhaust gas pressure that can reproduce more positive work. In the modeled supercharged engine, results showed that brake thermal efficiency can be improved by about 17%, and brake power by about 17.4%.

  18. Study of exhaust emissions of direct injection diesel engine operating on ethanol, petrol and rapeseed oil blends

    International Nuclear Information System (INIS)

    Labeckas, Gvidonas; Slavinskas, Stasys

    2009-01-01

    This article presents the bench testing results of a four stroke, four cylinder, direct injection, unmodified, diesel engine operating on pure rapeseed oil (RO) and its 2.5 vol%, 5 vol%, 7.5 vol% and 10 vol% blends with ethanol (ERO), petrol (PRO) and both improving agents applied in equal proportions as 50:50 vol% (EPRO). The purpose of the research is to examine the effect of ethanol and petrol addition into RO on diesel engine emission characteristics and smoke opacity of the exhausts. The biggest NO x emissions, 1954 and 2078 ppm, at 2000 min -1 speed generate blends PRO10 (9.72%) and EPRO5 (11.13%) against, 1731 and 1411 ppm, produced from ERO5 (12%) and ERO10 (13.2% oxygen) blends. The carbon monoxide, CO, emissions emitted from a fully loaded engine fuelled with three agent blends EPRO5-7.5 at maximum torque and rated speed are higher by 39.5-18.8% and 27.5-16.1% and smoke opacity lower by 3.3-9.0% and 24.1-17.6% comparing with RO case. When operating at rated 2200 min -1 mode, the carbon dioxide, CO 2 , emissions are lower, 6.9-6.3 vol%, from blends EPRO5-7.5 relative to that from RO, 7.8 vol%, accompanied by a slightly higher emission of unburned hydrocarbons HC, 16 ppm, and residual oxygen contents O 2 , 10.4-12.0 vol%, in the exhausts

  19. Numerical study on steam injection in a turbocompound diesel engine for waste heat recovery

    International Nuclear Information System (INIS)

    Zhao, Rongchao; Li, Weihua; Zhuge, Weilin; Zhang, Yangjun; Yin, Yong

    2017-01-01

    Highlights: • Steam injection was adopted in a turbocompound engine to further recover waste heat. • Thermodynamics model for the turbocompound engine was established and calibrated. • Steam injection at CT inlet obtained lower engine BSFC than injection at PT inlet. • The optimal injected steam mass at different engine speeds was presented. • Turbocompounding combined with steam injection can reduce the BSFC by 6.0–11.2%. - Abstract: Steam injection and turbocompouding are both effective methods for engine waste heat recovery. The fuel saving potential obtained by the combination of the two methods is not clear. Based on a turbocompound engine developed in the previous study, the impacts of pre-turbine steam injection on the fuel saving potentials of the turbocompound engine were investigated in this paper. Firstly, thermodynamic cycle model for the baseline turbocompound engine is established using commercial software GT-POWER. The cycle model is calibrated with the experiment data of the turbocompound engine and achieves high accuracy. After that, the influences of steam mass flow rate, evaporating pressure and injection location on the engine performance are studied. In addition, the impacts of hot liquid water injection are also investigated. The results show that steam injection at the turbocharger turbine inlet can reduce the turbocompound engine BSFC at all speed conditions. The largest fuel reduction 6.15% is obtained at 1000 rpm condition. However, steam injection at power turbine inlet can only lower the BSFC at high speed conditions. Besides, it is found that hot liquid water injection in the exhaust cannot improve the engine performance. When compared with the conventional turbocharged engine, the combination of turbocompounding and steam injection can reduce the BSFC by 6.0–11.2% over different speeds.

  20. Investigations of effects of pilot injection with change in level of compression ratio in a common rail diesel engine

    Directory of Open Access Journals (Sweden)

    Gajarlawar Nilesh

    2013-01-01

    Full Text Available These day diesel engines are gaining lots of attention as prime movers for various source of transportation. It offers better drive ability, very good low end torque and importantly the lower CO2 emission. Diesel engines are bridging the gap between gasoline and diesel engines. Better noise vibration and harshness levels of gasoline engine are realized to great extent in diesel engine, thanks to common rail direct injection system. Common rail injection system is now well known entity. Its unique advantage is flexible in operation. In common rail injection system, number of injection prior and after main injection at different injection pressure is possible. Due to multiple injections, gain in emission reduction as well as noise has been already experienced and demonstrated by researcher in the past. However, stringent emission norms for diesel engine equipped vehicle demands for further lower emission of oxides of nitrogen (NOx and particulate matter (PM. In the present paper, authors attempted to study the effect of multiple injections in combination with two level of compression ratio. The aim was to study the combustion behavior with the reduced compression ratio which is going to be tried out as low temperature combustion concept in near future. The results were compared with the current level of compression ratio. Experiments were carried out in 2.2L cubic capacity engine with two levels of compression ratios. Pilot injection separation and quantities were varied keeping the main injection, rail pressure, boost pressure and EGR rate constant. Cylinder pressure traces and gross heat release rates were measured and analyzed to understand the combustion behavior.

  1. Effect of Fuel Injection Strategy on the Carbonaceous Structure Formation and Nanoparticle Emission in a DISI Engine Fuelled with Butanol

    Directory of Open Access Journals (Sweden)

    Simona Silvia Merola

    2017-06-01

    Full Text Available Within the context of ever wider expansion of direct injection in spark ignition engines, this investigation was aimed at improved understanding of the correlation between fuel injection strategy and emission of nanoparticles. Measurements performed on a wall guided engine allowed identifying the mechanisms involved in the formation of carbonaceous structures during combustion and their evolution in the exhaust line. In-cylinder pressure was recorded in combination with cycle-resolved flame imaging, gaseous emissions and particle size distribution. This complete characterization was performed at three injection phasing settings, with butanol and commercial gasoline. Optical accessibility from below the combustion chamber allowed visualization of diffusive flames induced by fuel deposits; these localized phenomena were correlated to observed changes in engine performance and pollutant species. With gasoline fueling, minor modifications were observed with respect to combustion parameters, when varying the start of injection. The alcohol, on the other hand, featured marked sensitivity to the fuel delivery strategy. Even though the start of injection was varied in a relatively narrow crank angle range during the intake stroke, significant differences were recorded, especially in the values of particle emissions. This was correlated to the fuel jet-wall interactions; the analysis of diffusive flames, their location and size confirmed the importance of liquid film formation in direct injection engines, especially at medium and high load.

  2. Developments in Spray Modeling in Diesel and Direct-Injection Gasoline Engines Progrès de la modélisation des sprays dans les moteurs Diesel et à essence

    Directory of Open Access Journals (Sweden)

    Kong S. C.

    2006-12-01

    Full Text Available In direct-injection engines, the fuel spray characteristics influence the combustion efficiency and exhaust emissions. The performance of available spray models for predicting liquid and vapor fuel distributions, and their influence on combustion is reviewed for both diesel and gasoline direct injection engines. A phenomenological nozzle flow model is described for simulating the effects of diesel injector nozzle internal geometry on the fuel injection and spray processes. The flow model provides initial conditions for the liquid jet breakup model that considers wave instabilities due to Kelvin-Helmholtz (KH and Rayleigh-Taylor (RT mechanisms. A linearized instability analysis has also been extended to consider the breakup of liquid sheets for modeling pressure-swirl gasoline injectors. Diesel engine predictions have been compared with extensive data from in-cylinder laser diagnostics carried out in optically accessible heavy-duty, DI Diesel engines over a wide range of operating conditions. The results show that the nozzle flow model used in combination with the KH and RT models gives realistic spray predictions. In particular, the limited liquid fuel penetration length observed experimentally and the flame shape details are captured accurately. The liquid sheet breakup model has also been compared favorably with experimental spray penetration and drop size data for gasoline hollow-cone sprays. This model is currently being applied to study stratified charge combustion in GDI engines. Dans les moteurs à injection directe, les caractéristiques du spray de carburant influent directement sur le rendement et les émissions. Les performances des modèles de spray existants et leur influence sur la combustion pour les moteurs Diesel et essence à injection directe sont analysées. Un modèle phénoménologique d'écoulement dans les injecteurs indiquant les effets de la géométrie sur les processus d'injection est présenté. Ce modèle donne les

  3. Effects of a catalytic volatile particle remover (VPR) on the particulate matter emissions from a direct injection spark ignition engine.

    Science.gov (United States)

    Xu, Fan; Chen, Longfei; Stone, Richard

    2011-10-15

    Emissions of fine particles have been shown to have a large impact on the atmospheric environment and human health. Researchers have shown that gasoline engines, especially direct injection spark ignition (DISI) engines, tend to emit large amounts of small size particles compared to diesel engines fitted with diesel particulate filters (DPFs). As a result, the particle number emissions of DISI engines will be restricted by the forthcoming EU6 legislation. The particulate emission level of DISI engines means that they could face some challenges in meeting the EU6 requirement. This paper is an experimental study on the size-resolved particle number emissions from a spray guided DISI engine and the performance of a catalytic volatile particle remover (VPR), as the EU legislation seeks to exclude volatile particles. The performance of the catalytic VPR was evaluated by varying its temperature and the exhaust residence time. The effect of the catalytic VPR acting as an oxidation catalyst on particle emissions was also tested. The results show that the catalytic VPR led to a marked reduction in the number of particles, especially the smaller size (nucleation mode) particles. The catalytic VPR is essentially an oxidation catalyst, and when post three-way catalyst (TWC) exhaust was introduced to the catalytic VPR, the performance of the catalytic VPR was not affected much by the use of additional air, i.e., no significant oxidation of the PM was observed.

  4. Effects of thermal barrier coating on gas emissions and performance of a LHR engine with different injection timings and valve adjustments

    International Nuclear Information System (INIS)

    Bueyuekkaya, Ekrem; Engin, Tahsin; Cerit, Muhammet

    2006-01-01

    Tests were performed on a six cylinder, direct injection, turbocharged Diesel engine whose pistons were coated with a 350 μm thickness of MgZrO 3 over a 150 μm thickness of NiCrAl bond coat. CaZrO 3 was employed as the coating material for the cylinder head and valves. The working conditions for the standard engine (uncovered) and low heat rejection (LHR) engine were kept exactly the same to ensure a realistic comparison between the two configurations of the engine. Comparisons between the standard engine and its LHR version were made based on engine performance, exhaust gas emissions, injection timing and valve adjustment. The results showed that 1-8% reduction in brake specific fuel consumption could be achieved by the combined effect of the thermal barrier coating (TBC) and injection timing. On the other hand, NO x emissions were obtained below those of the base engine by 11% for 18 o BTDC injection timing

  5. Injectable Anisotropic Nanocomposite Hydrogels Direct in Situ Growth and Alignment of Myotubes

    International Nuclear Information System (INIS)

    De France, Kevin J.; Yager, Kevin G.; Chan, Katelyn J. W.; Corbett, Brandon; Cranston, Emily D.; Hoare, Todd

    2017-01-01

    Here, while injectable in situ cross-linking hydrogels have attracted increasing attention as minimally invasive tissue scaffolds and controlled delivery systems, their inherently disorganized and isotropic network structure limits their utility in engineering oriented biological tissues. Traditional methods to prepare anisotropic hydrogels are not easily translatable to injectable systems given the need for external equipment to direct anisotropic gel fabrication and/or the required use of temperatures or solvents incompatible with biological systems. Herein, we report a new class of injectable nanocomposite hydrogels based on hydrazone cross-linked poly(oligoethylene glycol methacrylate) and magnetically aligned cellulose nanocrystals (CNCs) capable of encapsulating skeletal muscle myoblasts and promoting their differentiation into highly oriented myotubes in situ. CNC alignment occurs on the same time scale as network gelation and remains fixed after the removal of the magnetic field, enabling concurrent CNC orientation and hydrogel injection. The aligned hydrogels show mechanical and swelling profiles that can be rationally modulated by the degree of CNC alignment and can direct myotube alignment both in two- and three-dimensions following coinjection of the myoblasts with the gel precursor components. As such, these hydrogels represent a critical advancement in anisotropic biomimetic scaffolds that can be generated noninvasively in vivo following simple injection.

  6. Effect of Exhaust Gas Recirculation (EGR on the Performance Characteristics of a Direct Injection Multi Cylinders Diesel Engine

    Directory of Open Access Journals (Sweden)

    Khalil Ibrahim Abaas

    2016-07-01

    Full Text Available Owing  to  the  energy  crisis  and  pollution  problems  of  today  investigations  have  concentrated  on decreasing  fuel  consumption  and  on  lowering  the  concentration  of  toxic  components  in  combustion products by using exhaust gas after treatments methods like PM filters and EGR for NOx reduction. In this study, the combustion characteristics of diesel fuel were compared with that pr oduced from adding EGR at several percentages to air manifold. The tests were performed in a four-cylinder direct injection (DI diesel engine at constant engine speed (1500 rpm and variable loads (from no load to 86 kN/m2, the tests were repeated with constant load (77 kN/m2 and variable engine speeds (from 1250 to 3000 rpm.The experimental results showed that adding EGR to diesel engine provided significant reductions in brake power (bp, brake thermal efficiency and exhaust gas temperatures, while high increments in brake specific  fuel  consumption  (bsfc.  High  EGR  percentage  (as  30%  in  this  article  caused  an  11.7% reduction  in  brake  thermal  efficiency,  26.38%  reduction  in  exhaust  gas  temperatures  and  12.28%  in volumetric efficiency at full load conditions.

  7. A Study on the Optimal Actuation Structure Design of a Direct Needle-Driven Piezo Injector for a CRDi Engine

    Directory of Open Access Journals (Sweden)

    Sangik Han

    2017-03-01

    Full Text Available Recently, the high-pressure fuel injection performance of common-rail direct injection (CRDi engines has become more important, due to the need to improve the multi-injection strategy. A multiple injection strategy provides better emission and fuel economy characteristics than a normal single injection scheme. The CRDi engine performance changes with the type of high-pressure electro-mechanical injector that is used and its injection response in a multi-injection scheme. In this study, a direct needle-driven piezo injector (DPI was investigated, to optimize its actuation components, including the plate length, number of springs, and the elasticity of the spring between the injector needle and the piezo stack. Three prototype DPIs were proposed by this research. They were classified as Type 1, 2, and 3, depending on whether the injector needle was hydraulic or mechanical. Then, the optimal prototype was determined by conducting four evaluation experiments analyzing the maximum injection pressure, injection rate, spray visualization, and real engine combustion application. As a result, it was found that the Type 3 DPI prototype, with several pan-springs and plates, had the highest injection pressure, a steady injection rate, and the fastest spray speed. It also demonstrated the most effective emission reduction for a two-stage rapid spray injection in a single-cylinder CRDi engine. The Type 3 DPI displays an increased elasticity from its hydraulic needle that provides a synergy effect for improving DPI actuation.

  8. Quantitative planar laser-induced fluorescence imaging of multi-component fuel/air mixing in a firing gasoline-direct-injection engine: Effects of residual exhaust gas on quantitative PLIF

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Ben; Ewart, Paul [Department of Physics, Oxford University, Parks Road, Oxford OX1 3PU (United Kingdom); Wang, Xiaowei; Stone, Richard [Department of Engineering Science, Oxford University, Parks Road, Oxford OX1 3PJ (United Kingdom); Ma, Hongrui; Walmsley, Harold; Cracknell, Roger [Shell Global Solutions (UK), Shell Research Centre Thornton, P. O. Box 1, Chester, CH1 3SH (United Kingdom); Stevens, Robert; Richardson, David; Fu, Huiyu; Wallace, Stan [Jaguar Cars, Engineering Centre, Abbey Road, Whitley, Coventry, CV3 4LF (United Kingdom)

    2010-10-15

    A study of in-cylinder fuel-air mixing distributions in a firing gasoline-direct-injection engine is reported using planar laser-induced fluorescence (PLIF) imaging. A multi-component fuel synthesised from three pairs of components chosen to simulate light, medium and heavy fractions was seeded with one of three tracers, each chosen to co-evaporate with and thus follow one of the fractions, in order to account for differential volatility of such components in typical gasoline fuels. In order to make quantitative measurements of fuel-air ratio from PLIF images, initial calibration was by recording PLIF images of homogeneous fuel-air mixtures under similar conditions of in-cylinder temperature and pressure using a re-circulation loop and a motored engine. This calibration method was found to be affected by two significant factors. Firstly, calibration was affected by variation of signal collection efficiency arising from build-up of absorbing deposits on the windows during firing cycles, which are not present under motored conditions. Secondly, the effects of residual exhaust gas present in the firing engine were not accounted for using a calibration loop with a motored engine. In order to account for these factors a novel method of PLIF calibration is presented whereby 'bookend' calibration measurements for each tracer separately are performed under firing conditions, utilising injection into a large upstream heated plenum to promote the formation of homogeneous in-cylinder mixtures. These calibration datasets contain sufficient information to not only characterise the quantum efficiency of each tracer during a typical engine cycle, but also monitor imaging efficiency, and, importantly, account for the impact of exhaust gas residuals (EGR). By use of this method EGR is identified as a significant factor in quantitative PLIF for fuel mixing diagnostics in firing engines. The effects of cyclic variation in fuel concentration on burn rate are analysed for

  9. Thixotropic injectable hydrogel using a polyampholyte and nanosilicate prepared directly after cryopreservation

    Energy Technology Data Exchange (ETDEWEB)

    Jain, Minkle; Matsumura, Kazuaki, E-mail: mkazuaki@jaist.ac.jp

    2016-12-01

    Success of tissue engineering applications in regenerative medicine requires the preservation of tissue-engineered products at a low temperature. This can be successfully achieved by the use of cryoprotective agent (CPA). In this study, we formulated a unique injectable hydrogel for the purpose of cell delivery after cryopreservation by using polyampholyte CPA. The polyampholyte showed excellent post-thaw cell survival, and after thawing, the polymeric CPA did not have to be removed because of its low cytotoxicity. The polyampholyte could be transformed into a hydrogel by mixing with nanosilicates. Previously, nanosilicates were used to improve mechanical properties, but this is the first report of the use of a nanosilicate together with CPA to formulate hydrogels. Inclusion of the nanosilicate led to the formation of thixotropic hydrogels, which can be injected using fine needles. These gels with tunable mechanical properties can be injected into defect sites to form scaffolds for cell growth and tissue repair, and they do not require any separate seeding of cells before injection, thus eliminating the need for cell harvesting and cell maintenance. This is a distinct system in which cells can be cryopreserved until before usage; when required, the cells in the polyampholyte can be revived to their original state and the thixotropic hydrogel can be formed. The combination of thixotropy and cytocompatibility of the gels could enable a wide range of biomedical applications such as cell delivery and orthopedic repair. - Graphical abstract: A novel thixotropic, cytocompatible and injectable nanocomposite hydrogel with tunable mechanical properties directly after cryopreservation was formulated using an efficient polymer cryoprotectant and laponite. This is an efficient system in which cells remain viable and can proliferate even after one week. The combined use of thixotropy and cytocompatibility enables this system to be used for cell delivery applications

  10. Mixture formation of direct gasoline injection engine. In cylinder gas sampling using fast response ionization detector; Tonai funsha gasoline engine no kongoki keisei. Kosoku FID ni yoru tonai gas sampling

    Energy Technology Data Exchange (ETDEWEB)

    Yamashita, H; Marubara, M; Ota, N; Kudo, H; Yamamoto, H [Mazda Motor Corp., Hiroshima (Japan)

    1997-10-01

    Local mixture concentration near the spark plug of a direct gasoline injection engine was observed by a fast flame ionization detector. To ensure combustion stability and good fuel economy in DISC operation, the swirl ratio and the piston configuration were optimized. Swirl is needed to retain well-vaporized and stable mixture near the spark plug especially in light load. And adequate volume in piston cavity is required for trapping curved fuel spray in it. With these specifications, the fuel economy improvement of 13 to 30 % was realized. 2 refs., 13 figs., 1 tab.

  11. Effects of injection angles on combustion processes using multiple injection strategies in an HSDI diesel engine

    Energy Technology Data Exchange (ETDEWEB)

    Tiegang Fang; Robert E. Coverdill; Chia-fon F. Lee; Robert A. White [North Carolina State University, Raleigh, NC (United States). Department of Mechanical and Aerospace Engineering

    2008-11-15

    Effects of injection angles and injection pressure on the combustion processes employing multiple injection strategies in a high-speed direct-injection (HSDI) diesel engine are presented in this work. Whole-cycle combustion and liquid spray evolution processes were visualized using a high-speed video camera. NOx emissions were measured in the exhaust pipe. Different heat release patterns are seen for two different injectors with a 70-degree tip and a 150-degree tip. No evidence of fuel-wall impingement is found for the first injection of the 150-degree tip, but for the 70-degree tip, some fuel impinges on the bowl wall and a fuel film is formed. For the second injection, a large amount of fuel deposition is observed for the 70-degree tip. Weak flame is seen for the first injection of the 150-degree tip while two sorts of flames are seen for the first injection of the 70-degree tip including an early weak flame and a late luminous film combustion flame. Ignition occurs near the spray tip in the vicinity of the bowl wall for the second injection events of the 150-degree tip, however, it is near the injector tip in the central region of the bowl for the 70-degree tip. The flame is more homogeneous for the 150-degree tip with higher injection pressure with little soot formation similar to a premixed-charge-compression-ignition (PCCI) combustion. For other cases, liquid fuel is injected into flames showing diffusion flame combustion. More soot luminosity is seen for the 70-degree tip due to significant fuel film deposition on the piston wall with fuel film combustion for both injection events. Lower NOx emissions were obtained for the narrow-angle injector due to the rich air-fuel mixture near the bowl wall during the combustion process. 30 refs., 11 figs., 3 tabs.

  12. Near-frictionless carbon coatings for spark-ignited direct-injected fuel systems. Final report, January 2002.; TOPICAL

    International Nuclear Information System (INIS)

    Hershberger, J.; Ozturk, O.; Ajayi, O. O.; Woodford, J. B.; Erdemir, A.; Fenske, G. R.

    2002-01-01

    This report describes an investigation by the Tribology Section of Argonne National Laboratory (ANL) into the use of near-frictionless carbon (NFC) coatings for spark-ignited, direct-injected (SIDI) engine fuel systems. Direct injection is being pursued in order to improve fuel efficiency and enhance control over, and flexibility of, spark-ignited engines. SIDI technology is being investigated by the Partnership for a New Generation of Vehicles (PNGV) as one route towards meeting both efficiency goals and more stringent emissions standards. Friction and wear of fuel injector and pump parts were identified as issues impeding adoption of SIDI by the OTT workshop on ''Research Needs Related to CIDI and SIDI Fuel Systems'' and the resulting report, Research Needs Related to Fuel Injection Systems in CIDI and SIDI Engines. The following conclusions were reached: (1) Argonne's NFC coatings consistently reduced friction and wear in existing and reformulated gasolines. (2) Compared to three commercial DLC coatings, NFC provided the best friction reduction and protection from wear in gasoline and alternative fuels. (3) NFC was successfully deposited on production fuel injectors. (4) Customized wear tests were performed to simulate the operating environment of fuel injectors. (5) Industry standard lubricity test results were consistent with customized wear tests in showing the friction and wear reduction of NFC and the lubricity of fuels. (6) Failure of NFC coatings by tensile crack opening or spallation did not occur, and issues with adhesion to steel substrates were eliminated. (7) This work addressed several of the current research needs of the OAAT SIDI program, as defined by the OTT report Research Needs Related to Fuel Injection Systems in CIDI and SIDI Engines

  13. 78 FR 9007 - Airworthiness Directives; Turbomeca S.A. Turboshaft Engines

    Science.gov (United States)

    2013-02-07

    ... require, depending on the engine model, repetitive replacements of fuel injection manifolds and the... injection manifolds found during inspections at a repair workshop. We issued that AD to prevent engine... engines, initial and repetitive replacement of the fuel injection manifold and the privilege injector...

  14. A Second Generation Swirl-Venturi Lean Direct Injection Combustion Concept

    Science.gov (United States)

    Tacina, Kathleen M.; Chang, Clarence T.; He, Zhuohui Joe; Lee, Phil; Dam, Bidhan; Mongia, Hukam

    2014-01-01

    A low-NO (sub x) aircraft gas turbine engine combustion concept was developed and tested. The concept is a second generation swirl-venturi lean direct injection (SV-LDI) concept. LDI is a lean-burn combustion concept in which the fuel is injected directly into the flame zone. Three second generation SV-LDI configurations were developed. All three were based on the baseline 9-point SV-LDI configuration reported previously. These second generation configurations had better low power operability than the baseline 9-point configuration. Two of these second generation configurations were tested in a NASA Glenn Research Center flametube; these two configurations are called the at dome and 5-recess configurations. Results show that the 5-recess configuration generally had lower NO (sub x) emissions than the flat dome configuration. Correlation equations were developed for the flat dome configuration so that the landing-takeoff NO (sub x) emissions could be estimated. The flat dome landing-takeoff NO (sub x) is estimated to be 87-88 percent below the CAEP/6 standards, exceeding the ERA project goal of 75 percent reduction.

  15. Improvement of combustion in a direct injection diesel engine by the use of a combustion-hole injection nozzle; Kumiawase funko nozzle ni yoru chokusetsu funshashiki diesel engine no nensho kaizen

    Energy Technology Data Exchange (ETDEWEB)

    Shoji, T. [Mitsubishi Motors Corp., Tokyo (Japan); Kamimoto, T. [Tokyo Institute of Technology, Tokyo (Japan)

    1998-04-25

    Suppression of pre-mixed combustion and activation of diffusion combustion in DI diesel engines are known to be effective in reducing both NOx and fuel consumption. To achieve this concept, the authors have proposed a new type of fuel injection nozzle named combination-hole nozzle. This nozzle has very small holes with a diameter of 0.13 mm below (sub holes) for reducing ignition delay and normal holes (main holes) for keeping reasonable injection duration. The experiments conducted with a single cylinder research engine revealed that the combination-hole nozzle reduced the ignition delay and the peak value of the rate of heat release during the premixed combustion by 10% and 40% respectively compared with the experimental results of conventional nozzles and that the trade-off curve between NOx and fuel consumption sifted to the low level corner at half and full load conditions at a low engine speed. The reason for this improvement was investigated by the measurement of flame temperature distribution in the combustion chamber by means of the two colors method. The result revealed that the flame temperature in regions between sub and main hole`s flames of the nozzle was lower than that of the flames of a conventional nozzle at a full load and a low speed condition. 13 refs., 10 figs., 3 tabs.

  16. Investigation of In-Cylinder Steam Injection in a Turbocharged Diesel Engine for Waste Heat Recovery and NOx Emission Control

    OpenAIRE

    Zhongbo Zhang; Lifu Li

    2018-01-01

    In this study, an in-cylinder steam injection method is introduced and applied to a turbocharged diesel engine for waste heat recovery and NOx emission reduction. In the method, cool water was first heated into superheated steam by exhaust. Then the superheated steam was directly injected into the cylinder during the compression stroke. The potential for fuel savings and NOx emission reduction obtained by this method was investigated. First, a two-zone combustion model for the baseline engine...

  17. Linking instantaneous rate of injection to X-ray needle lift measurements for a direct-acting piezoelectric injector

    International Nuclear Information System (INIS)

    Viera, Juan P.; Payri, Raul; Swantek, Andrew B.; Duke, Daniel J.; Sovis, Nicolas; Kastengren, Alan L.; Powell, Christopher F.

    2016-01-01

    Highlights: • A direct-acting prototype diesel injector is utilized to control needle lift. • The effects of partial needle lift on rate of injection are analyzed. • Time-resolved needle lift is measured from fast phase-contrast X-ray images. • The link between instantaneous needle lift and rate of injection is analyzed. - Abstract: Internal combustion engines have been and still are key players in today’s world. Ever increasing fuel consumption standards and the ongoing concerns about exhaust emissions have pushed the industry to research new concepts and develop new technologies that address these challenges. To this end, the diesel direct injection system has recently seen the introduction of direct-acting piezoelectric injectors, which provide engineers with direct control over the needle lift, and thus instantaneous rate of injection (ROI). Even though this type of injector has been studied previously, no direct link between the instantaneous needle lift and the resulting rate of injection has been quantified. This study presents an experimental analysis of the relationship between instantaneous partial needle lifts and the corresponding ROI. A prototype direct-acting injector was utilized to produce steady injections of different magnitude by partially lifting the needle. The ROI measurements were carried out at CMT-Motores Térmicos utilizing a standard injection rate discharge curve indicator based on the Bosch method (anechoic tube). The needle lift measurements were performed at the Advanced Photon Source at Argonne National Laboratory. The analysis seeks both to contribute to the current understanding of the influence that partial needle lifts have over the instantaneous ROI and to provide experimental data with parametric variations useful for numerical model validations. Results show a strong relationship between the steady partial needle lift and the ROI. The effect is non-linear, and also strongly dependent on the injection pressure. The

  18. 78 FR 32551 - Airworthiness Directives; Turbomeca S.A. Turboshaft Engines

    Science.gov (United States)

    2013-05-31

    ... damage. This new AD requires, depending on the engine model, repetitive replacements of fuel injection...). That NPRM proposed to require, depending on the engine model, repetitive replacements of fuel injection... injection manifolds and privilege injectors (Arrius 2B1 enignes) and, privilege injectors (Arrius 2F engines...

  19. The investigation of soot and temperature distributions in a visualized direct injection diesel engine using laser diagnostics

    Science.gov (United States)

    Han, Yong-taek; Kim, Ki-bum; Lee, Ki-hyung

    2008-11-01

    Based upon the method of temperature calibration using the diffusion flame, the temperature and soot concentrations of the turbulent flame in a visualized diesel engine were qualitatively measured. Two different cylinder heads were used to investigate the effect of swirl ratio within the combustion chamber. From this experiment, we find that the highest flame temperature of the non-swirl head engine is approximately 2400 K and that of the swirl head engine is 2100 K. In addition, as the pressure of fuel injection increases, the in-cylinder temperature increases due to the improved combustion of a diesel engine. This experiment represented the soot quantity in the KL factor and revealed that the KL factor was high when the fuel collided with the cylinder wall. Moreover, the KL factor was also high in the area of the chamber where the temperature dropped rapidly.

  20. 3d Modeling of Combustion for Di-Si Engines Modélisation 3D de la combustion dans les moteurs à injection directe d'essence

    Directory of Open Access Journals (Sweden)

    Duclos J. P.

    2006-12-01

    Full Text Available Direct injection of gasoline is a promising concept to reduce fuel consumption of SI engines. The development of GDI engines is difficult and 3D CFD is a way to support its design. It requires models able to describe the spray and its evaporation and combustion. This paper presents a model, the ECFM, that enables to compute combustion for stratified load in the GDI engines. This model is a development of the Coherent Flame Model which includes thermal expansion effects, and is coupled with a burnt/unburnt gases conditionnal thermodynamic properties description. The model is validated by comparing measurements and computations on the GDI Mitsubishi engine in production. L'injection directe d'essence (IDE est un concept prometteur pour les moteurs à allumage commandé. La mise au point de ce type de moteur est néanmoins délicate, et le calcul 3D des chambres de combustion est un moyen d'aider à leur conception. Ceci nécessite cependant de disposer de modèles adaptés, à même de décrire le jet d'essence, son évaporation et la combustion du mélange créé. Cet article présente un modèle ECFM de simulation de la combustion dans les moteurs IDE, y compris en fonctionnement stratifié. C'est un développement du modèle flamme cohérente qui comprend des effets d'expansion thermique et est couplé avec une description conditionnelle gaz frais/gaz brûlés des grandeurs thermodynamiques. Ce modèle a été validé par rapprochement de mesures et simulations sur le moteur GDI Mitsubishi.

  1. Fueling an D.I. agricultural diesel engine with waste oil biodiesel: Effects over injection, combustion and engine characteristics

    International Nuclear Information System (INIS)

    Radu, Rosca; Petru, Carlescu; Edward, Rakosi; Gheorghe, Manolache

    2009-01-01

    The paper presents the results of a research concerning the use of a biodiesel type fuel in D.I. Diesel engine; the fuel injection system and the engine were tested. The results indicated that the injection characteristics are affected when a blend containing 50% methyl ester and 50% petrodiesel is used as fuel (injection duration, pressure wave propagation time, average injection rate, peak injection pressure). As a result, the engine characteristics are also affected, the use of the biodiesel blend leading to lower output power and torque; the lower autoignition delay and pressure wave propagation time led to changes of the cylinder pressure and heat release traces and to lower peak combustion pressures.

  2. 78 FR 70240 - Airworthiness Directives; Lycoming Engines, Fuel Injected Reciprocating Engines

    Science.gov (United States)

    2013-11-25

    .... Mail: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12... receipt. FOR FURTHER INFORMATION CONTACT: Norm Perenson, Aerospace Engineer, New York Aircraft..., Supplement 1, dated August 29, 2013 to identify previously omitted engine models. FAA's Determination We are...

  3. Comparative performance of direct injection diesel engine operating on ethanol, petrol and rapeseed oil blends

    International Nuclear Information System (INIS)

    Labeckas, Gvidonas; Slavinskas, Stasys

    2009-01-01

    This article presents the bench testing results of a four stroke, four cylinder, direct injection, unmodified, diesel engine operating on pure rapeseed oil (RO) and its 2.5 vol%, 5 vol%, 7.5 vol% and 10 vol% blends with ethanol (ERO), petrol (PRO) and both improving agents applied in equal proportions as 50:50 vol% (EPRO). The purpose of the research is to examine the effect of ethanol and petrol addition into RO on the biofuel kinematical viscosity, brake mean effective pressure (bmep), brake specific fuel consumption (bsfc) of a diesel engine and its brake thermal efficiency (bte). Addition into RO from 2.5 to 7.5 vol% of ethanol and petrol its viscosity at ambient temperature of 20 deg. C diminishes by 9.2-28.3% and 14.1-31.7%, respectively. Heating up to the temperature of 60 deg. C the viscosity of pure RO, blends ERO2.5-7.5 and PRO2.5-10 further diminishes 4.2, 3.9-3.8 and 3.9-3.6 times. At 1800 min -1 speed, the maximum brake mean effective pressure (bmep) higher up to 1.6% comparing with that of pure RO (0.77 MPa) ensure three agent blends EPRO5-7.5, whereas at rated 2200 min -1 speed, the bmep higher by 5.6% can be obtained when fuelling the engine with blend PRO2.5. Brake specific fuel consumption (bsfc) at maximum torque (240.2 g/kWh) and rated power (234.0 g/kWh) is correspondingly lower by 3.4% and 5.5% in comparison with pure RO when biofuel blends EPRO5 and PRO2.5 are used. The biggest brake thermal efficiency at maximum torque (0.40-0.41) and rated power (0.42-0.43) relative to that of RO (0.39) suggest blends PRO2.5 and EPRO5-7.5, respectively

  4. Piezoelectric Injection Systems

    Science.gov (United States)

    Mock, R.; Lubitz, K.

    The origin of direct injection can be doubtlessly attributed to Rudolf Diesel who used air assisted injection for fuel atomisation in his first self-ignition engine. Although it became apparent already at that time that direct injection leads to reduced specific fuel consumption compared to other methods of fuel injection, it was not used in passenger cars for the moment because of its disadvantageous noise generation as the requirements with regard to comfort were seen as more important than a reduced specific consumption.

  5. Thermodynamic modeling of direct injection methanol fueled engines

    International Nuclear Information System (INIS)

    Shen Yuan; Bedford, Joshua; Wichman, Indrek S.

    2009-01-01

    In-cylinder pressure is an important parameter that is used to investigate the combustion process in internal combustion (IC) engines. In this paper, a thermodynamic model of IC engine combustion is presented and examined. A heat release function and an empirical conversion efficiency factor are introduced to solve the model. The pressure traces obtained by solving the thermodynamic model are compared with measured pressure data for a fully instrumented laboratory IC spark ignition (SI) engine. Derived scaling parameters for time to peak pressure, peak pressure, and maximum rate of pressure rise (among others) are developed and compared with the numerical simulations. The models examined here may serve as pedagogic tools and, when suitably refined, as preliminary design tools.

  6. Exhaust emissions from an indirect injection dual-fuel engine

    International Nuclear Information System (INIS)

    Abd Alla, G.H.; Badr, O.A.; Soliman, H.A.; Abd Rabbo, M.F.

    2000-01-01

    Diesel engines operating on gaseous fuels are commonly known as dual-fuel engines. In the present work, a single-cylinder, compression ignition, indirect injection research (Ricardo E6) engine has been installed at United Arab Emirates University for investigation of the exhaust emissions when the engine is operating as a dual-fuel engine. The influence of changes in major operating and design parameters, such as the concentration of gaseous fuel in the cylinder charge, pilot fuel quantity, injection timing and intake temperature, on the production of exhaust emissions was investigated. Diesel fuel was used as the pilot fuel, while methane or propane was used as the main fuel which was inducted in the intake manifold and mixed with the intake air. The experimental investigations showed that the poor emissions at light loads can be improved significantly by increasing the concentration of gaseous fuel (total equivalence ratio), employing a large pilot fuel quantity, advancing the injection timing of the pilot fuel and increasing the intake temperature. It is demonstrated that, in general, any measure that tends to increase the size of the combustion regions within the overly lean cylinder charge will reduce markedly the concentrations of unburned hydrocarbons and carbon monoxide in the exhaust gases. (Author)

  7. Exhaust emissions from an indirect injection dual-fuel engine

    Energy Technology Data Exchange (ETDEWEB)

    Abd Alla, G.H.; Badr, O.A.; Soliman, H.A.; Abd Rabbo, M.F. [Zagazig Univ., Dept. of Mechanical Engineering, Cairo (Egypt)

    2000-04-01

    Diesel engines operating on gaseous fuels are commonly known as dual-fuel engines. In the present work, a single-cylinder, compression ignition, indirect injection research (Ricardo E6) engine has been installed at United Arab Emirates University for investigation of the exhaust emissions when the engine is operating as a dual-fuel engine. The influence of changes in major operating and design parameters, such as the concentration of gaseous fuel in the cylinder charge, pilot fuel quantity, injection timing and intake temperature, on the production of exhaust emissions was investigated. Diesel fuel was used as the pilot fuel, while methane or propane was used as the main fuel which was inducted in the intake manifold and mixed with the intake air. The experimental investigations showed that the poor emissions at light loads can be improved significantly by increasing the concentration of gaseous fuel (total equivalence ratio), employing a large pilot fuel quantity, advancing the injection timing of the pilot fuel and increasing the intake temperature. It is demonstrated that, in general, any measure that tends to increase the size of the combustion regions within the overly lean cylinder charge will reduce markedly the concentrations of unburned hydrocarbons and carbon monoxide in the exhaust gases. (Author)

  8. Experimental Investigation of the Effect of Hydrogen Manifold Injection on the Performance of Compression Ignition Engines

    OpenAIRE

    Haroun A.K. Shahad; Nabeel Abdul-Hadi

    2011-01-01

    Experiments were carried out to evaluate the influence of the addition of hydrogen to the inlet air on the performance of a single cylinder direct injection diesel engine. Hydrogen was injected in the inlet manifold. The addition of hydrogen was done on energy replacement basis. It was found that the addition of hydrogen improves the combustion process due to superior combustion characteristics of hydrogen in comparison to conventional diesel fuels. It was also found that...

  9. Effects of injection timing on the engine performance and exhaust emissions of a dual-fuel diesel engine

    International Nuclear Information System (INIS)

    Sayin, Cenk; Canakci, Mustafa

    2009-01-01

    In this study, influence of injection timing on the engine performance and exhaust emissions of a naturally aspirated, single cylinder diesel engine has been experimentally investigated when using ethanol blended diesel fuel from 0% to 15% with an increment of 5%. The engine load was selected as 15 and 30 Nm. The tests were conducted at five different injection timings (21 deg., 24 deg., 27 deg., 30 deg. and 33 deg. CA BTDC) by changing the thickness of advance shim. The experimental test results showed that BSFC and emissions of NO x and CO 2 increased as BTE and emissions of CO and HC decreased with increasing amount of ethanol in the fuel mixture. When compared to the results of original injection timing (27 deg. CA BTDC), NO x and CO 2 emissions increased, and unburned HC and CO emissions decreased for the retarded injection timings (21 deg. and 24 deg. CA BTDC) at the all test conditions. On the other side, with the advanced injection timings (30 deg. and 33 deg. CA BTDC), decreasing HC and CO emissions diminished, and NO x and CO 2 emissions boosted. In terms of BSFC and BTE, retarded and advanced injection timings compared to the original injection timing in the all fuel blends gave negative results for all engine speeds and loads

  10. Effects of injection timing on the engine performance and exhaust emissions of a dual-fuel diesel engine

    Energy Technology Data Exchange (ETDEWEB)

    Sayin, Cenk [Department of Mechanical Education, Marmara University, 34722 Istanbul (Turkey); Canakci, Mustafa [Department of Mechanical Education, Kocaeli University, 41380 Izmit (Turkey); Alternative Fuels R and D Center, Kocaeli University, 41040 Izmit (Turkey)

    2009-01-15

    In this study, influence of injection timing on the engine performance and exhaust emissions of a naturally aspirated, single cylinder diesel engine has been experimentally investigated when using ethanol blended diesel fuel from 0% to 15% with an increment of 5%. The engine load was selected as 15 and 30 Nm. The tests were conducted at five different injection timings (21 , 24 , 27 , 30 and 33 CA BTDC) by changing the thickness of advance shim. The experimental test results showed that BSFC and emissions of NO{sub x} and CO{sub 2} increased as BTE and emissions of CO and HC decreased with increasing amount of ethanol in the fuel mixture. When compared to the results of original injection timing (27 CA BTDC), NO{sub x} and CO{sub 2} emissions increased, and unburned HC and CO emissions decreased for the retarded injection timings (21 and 24 CA BTDC) at the all test conditions. On the other side, with the advanced injection timings (30 and 33 CA BTDC), decreasing HC and CO emissions diminished, and NO{sub x} and CO{sub 2} emissions boosted. In terms of BSFC and BTE, retarded and advanced injection timings compared to the original injection timing in the all fuel blends gave negative results for all engine speeds and loads. (author)

  11. Designing a Prototype LPG Injection Electronic Control Unit for a Carburetted Gasoline Engine

    Directory of Open Access Journals (Sweden)

    Barış ERKUŞ

    2015-07-01

    Full Text Available In this study, the originally carburetted gasoline engine was converted to gas-phase liquefied petroleum gas (LPG injection engine by using an after market LPG conversion kit's components except the electronic control unit (ECU. Instead of after market LPG injection ECU, the ECU which was designed considering the effects of  electromagnetic interference (EMI, was used for controlling injection. The designed ECU was tested in terms of EMI while the engine was being run and it was detected that the EMI noises could be suppressed as possible by taken measures. Designed ECU was used in performance tests at different engine conditions and the results obtained with LPG injection were compared with the results obtained with LPG carburetion. According to the performance test results, LPG injection ECU designed in this study could help to achieve low exhaust emissions and high engine performance.  

  12. Characterization of Swirl-Venturi Lean Direct Injection Designs for Aviation Gas-Turbine Combustion

    Science.gov (United States)

    Heath, Christopher M.

    2013-01-01

    Injector geometry, physical mixing, chemical processes, and engine cycle conditions together govern performance, operability and emission characteristics of aviation gas-turbine combustion systems. The present investigation explores swirl-venturi lean direct injection combustor fundamentals, characterizing the influence of key geometric injector parameters on reacting flow physics and emission production trends. In this computational study, a design space exploration was performed using a parameterized swirl-venturi lean direct injector model. From the parametric geometry, 20 three-element lean direct injection combustor sectors were produced and simulated using steady-state, Reynolds-averaged Navier-Stokes reacting computations. Species concentrations were solved directly using a reduced 18-step reaction mechanism for Jet-A. Turbulence closure was obtained using a nonlinear ?-e model. Results demonstrate sensitivities of the geometric perturbations on axially averaged flow field responses. Output variables include axial velocity, turbulent kinetic energy, static temperature, fuel patternation and minor species mass fractions. Significant trends have been reduced to surrogate model approximations, intended to guide future injector design trade studies and advance aviation gas-turbine combustion research.

  13. Effect of main injection timing for controlling the combustion phasing of a homogeneous charge compression ignition engine using a new dual injection strategy

    International Nuclear Information System (INIS)

    Das, Pranab; Subbarao, P.M.V.; Subrahmanyam, J.P.

    2015-01-01

    Highlights: • A new dual injection concept is developed by minimum geometry modification. • The occurrence of combustion parameters strongly depend on main injection timing. • At higher load, premixed equivalence ratio dominates over main injection timing. • Retarded of main injection timing tends to retard combustion phasing. • Slightly retarded main injection timing is recommended to avoid intense knocking. - Abstract: Homogeneous charge compression ignition combustion of diesel fuel is implemented using a novel dual injection strategy. A new experimental technique is developed to modify a single cylinder direct injection diesel engine to run on homogeneous combustion mode. Effect of main injection timing is investigated covering a range from 26 to 8 crank angle degrees before top dead center with an interval of 3°. Retarded main injection timing is identified as a control strategy for delaying combustion phasing and a means of controlled combustion phasing of direct injection homogeneous charge compression ignition combustion. Two load conditions were investigated and it was observed that at higher load, start of combustion depends more on fuel air equivalence ratio than main injection timing, whereas at low load, it significantly varies with varying main injection timing. Significant improvements in smoke and oxides of nitrogen emissions are observed when compared with the baseline conventional combustion. By studying different combustion parameters, it is observed that there is an improvement in performance and emissions with marginal loss in thermal efficiency when the main injection timing is 20° before top dead center. This is identified as the optimum main injection timing for such homogeneous combustion under the same operating condition

  14. Effects of Direct Fuel Injection Strategies on Cycle-by-Cycle Variability in a Gasoline Homogeneous Charge Compression Ignition Engine: Sample Entropy Analysis

    Directory of Open Access Journals (Sweden)

    Jacek Hunicz

    2015-01-01

    Full Text Available In this study we summarize and analyze experimental observations of cyclic variability in homogeneous charge compression ignition (HCCI combustion in a single-cylinder gasoline engine. The engine was configured with negative valve overlap (NVO to trap residual gases from prior cycles and thus enable auto-ignition in successive cycles. Correlations were developed between different fuel injection strategies and cycle average combustion and work output profiles. Hypothesized physical mechanisms based on these correlations were then compared with trends in cycle-by-cycle predictability as revealed by sample entropy. The results of these comparisons help to clarify how fuel injection strategy can interact with prior cycle effects to affect combustion stability and so contribute to design control methods for HCCI engines.

  15. Numerical Investigation Into Effect of Fuel Injection Timing on CAI/HCCI Combustion in a Four-Stroke GDI Engine

    Science.gov (United States)

    Cao, Li; Zhao, Hua; Jiang, Xi; Kalian, Navin

    2006-02-01

    The Controlled Auto-Ignition (CAI) combustion, also known as Homogeneous Charge Compression Ignition (HCCI), was achieved by trapping residuals with early exhaust valve closure in conjunction with direct injection. Multi-cycle 3D engine simulations have been carried out for parametric study on four different injection timings in order to better understand the effects of injection timings on in-cylinder mixing and CAI combustion. The full engine cycle simulation including complete gas exchange and combustion processes was carried out over several cycles in order to obtain the stable cycle for analysis. The combustion models used in the present study are the Shell auto-ignition model and the characteristic-time combustion model, which were modified to take the high level of EGR into consideration. A liquid sheet breakup spray model was used for the droplet breakup processes. The analyses show that the injection timing plays an important role in affecting the in-cylinder air/fuel mixing and mixture temperature, which in turn affects the CAI combustion and engine performance.

  16. Fuel injection system and method of operating the same for an engine

    Science.gov (United States)

    Topinka, Jennifer Ann [Niskayuna, NY; DeLancey, James Peter [Corinth, NY; Primus, Roy James [Niskayuna, NY; Pintgen, Florian Peter [Niskayuna, NY

    2011-02-15

    A fuel injector is coupled to an engine. The fuel injector includes an injection opening configured to vary in cross-section between a open state and a fully closed state. The fuel injector is configured to provide a plurality of discrete commanded fuel injections into an engine cylinder by modulating the size of the injection opening without completely closing the opening to the fully closed state.

  17. Highly efficient 6-stroke engine cycle with water injection

    Science.gov (United States)

    Szybist, James P; Conklin, James C

    2012-10-23

    A six-stroke engine cycle having improved efficiency. Heat is recovered from the engine combustion gases by using a 6-stroke engine cycle in which combustion gases are partially vented proximate the bottom-dead-center position of the fourth stroke cycle, and water is injected proximate the top-dead-center position of the fourth stroke cycle.

  18. Effects of Alumina Nano Metal Oxide Blended Palm Stearin Methyl Ester Bio-Diesel on Direct Injection Diesel Engine Performance and Emissions

    Science.gov (United States)

    Krishna, K.; Kumar, B. Sudheer Prem; Reddy, K. Vijaya Kumar; Charan Kumar, S.; Kumar, K. Ravi

    2017-08-01

    The Present Investigation was carried out to study the effect of Alumina Metal Oxide (Al2O3) Nano Particles as additive for Palm Stearin Methyl Ester Biodiesel (B 100) and their blends as an alternate fuel in four stroke single cylinder water cooled, direct injection diesel engine. Alumina Nano Particles has high calorific value and relatively high thermal conductivity (30-1 W m K-1) compare to diesel, which helps to promote more combustion in engines due to their higher thermal efficiency. In the experimentation Al2O3 were doped in various proportions with the Palm Stearin Methyl Ester Biodiesel (B-100) using an ultrasonicator and a homogenizer with cetyl trimethyl ammonium bromide (CTAB) as the cationic surfactant. The test were performed on a Kirsloskar DI diesel engine at constant speed of 1500 rpm using different Nano Biodiesel Fuel blends (psme+50 ppm, psme+150 ppm, and psme+200 ppm) and results were compared with those of neat conventional diesel and Palm Stearin Methyl Ester Bio diesel. It was observed that for Nano Biodiesel Fuel blend (psme+50ppm) there is an significant reduction in carbon monoxide (CO) emissions and Nox emissions compared to diesel and the brake thermal efficiency for (psme+50ppm) was almost same as diesel.

  19. Effect of advanced injection timing on the performance of rapeseed oil in diesel engines

    International Nuclear Information System (INIS)

    Nwafor, O.M.I.; Rice, G.; Ogbonna, A.I.

    2000-01-01

    Combustion studies on both diesel fuel and vegetable oil fuels, with the standard and advanced injection timing, were carried out using the same engine and test procedures so that comparative assessments may be made. The diesel engine principle demands self-ignition of the fuel as it is injected at some degrees before top dead centre (BTDC) into the hot compressed cylinder gas. Longer delays between injection and ignition lead to unacceptable rates of pressure rise with the result of diesel knock because too much fuel is ready to take part in premixed combustion. Alternative fuels have been noted to exhibit longer delay periods and slower burning rate especially at low load operating conditions hence resulting in late combustion in the expansion stroke. Advanced injection timing is expected to compensate these effects. The engine has standard injection timing of 30degC BTDC. The injection was first advanced by 5.5degC given injection timing of 35.5degC BTDC. The engine performance was very erratic on this timing. The injection was then advanced by 3.5degC and the effects are presented in this paper. The engine performance was smooth especially at low load levels. The ignition delay was reduced through advanced injection but tended to incur a slight increase in fuel consumption. Moderate advanced injection timing is recommended for low speed operations. (Author)

  20. The effect of rapeseed oil methyl ester on direct injection Diesel engine performance and exhaust emissions

    International Nuclear Information System (INIS)

    Labeckas, Gvidonas; Slavinskas, Stasys

    2006-01-01

    This article presents the comparative bench testing results of a four stroke, four cylinder, direct injection, unmodified, naturally aspirated Diesel engine when operating on neat RME and its 5%, 10%, 20% and 35% blends with Diesel fuel. The purpose of this research is to examine the effects of RME inclusion in Diesel fuel on the brake specific fuel consumption (bsfc) of a high speed Diesel engine, its brake thermal efficiency, emission composition changes and smoke opacity of the exhausts. The brake specific fuel consumption at maximum torque (273.5 g/kW h) and rated power (281 g/kW h) for RME is higher by 18.7% and 23.2% relative to Diesel fuel. It is difficult to determine the RME concentration in Diesel fuel that could be recognised as equally good for all loads and speeds. The maximum brake thermal efficiency varies from 0.356 to 0.398 for RME and from 0.373 to 0.383 for Diesel fuel. The highest fuel energy content based economy (9.36-9.61 MJ/kW h) is achieved during operation on blend B10, whereas the lowest ones belong to B35 and neat RME. The maximum NO x emissions increase proportionally with the mass percent of oxygen in the biofuel and engine speed, reaching the highest values at the speed of 2000 min -1 , the highest being 2132 ppm value for the B35 blend and 2107 ppm for RME. The carbon monoxide, CO, emissions and visible smoke emerging from the biodiesel over all load and speed ranges are lower by up to 51.6% and 13.5% to 60.3%, respectively. The carbon dioxide, CO 2 , emissions along with the fuel consumption and gas temperature, are slightly higher for the B20 and B35 blends and neat RME. The emissions of unburned hydrocarbons, HC, for all biofuels are low, ranging at 5-21 ppm levels

  1. Combustion of jojoba methyl ester in an indirect injection diesel engine

    Energy Technology Data Exchange (ETDEWEB)

    Selim, M.Y.E. [United Arab Emirates University, Al-Ain (United Arab Emirates). Mechanical Engineering Dept.; Radwan, M.S.; Elfeky, S.M.S. [Helwan University, Cairo (Egypt). Mechanical Power Engineering Dept.

    2003-07-01

    An experimental investigation has been carried out to examine for the first time the performance and combustion noise of an indirect injection diesel engine running with new fuel derived from pure jojoba oil, jojoba methyl ester, and its blends with gas oil. A Ricardo E6 compression swirl diesel engine was fully instrumented for the measurement of combustion pressure and its rise rate and other operating parameters. Test parameters included the percentage of jojoba methyl ester in the blend, engine speed, load, injection timing and engine compression ratio. Results showed that the new fuel derived from jojoba is generally comparable and a good replacement to gas oil in diesel engine at most engine operating conditions, in terms of performance parameters and combustion noise produced. (author)

  2. Numerical investigation on the combined effects of varying piston bowl geometries and ramp injection rate-shapes on the combustion characteristics of a kerosene-diesel fueled direct injection compression ignition engine

    International Nuclear Information System (INIS)

    Tay, Kun Lin; Yang, Wenming; Zhao, Feiyang; Yu, Wenbin; Mohan, Balaji

    2017-01-01

    Highlights: • Effect of injection rate-shaping on heat-release is significant with less turbulence. • Two peak heat-releases are seen for the shallow-depth re-entrant piston. • Significant combustion phasing occurs with kerosene usage and high turbulence. - Abstract: In this work, the combustion characteristics of a direct injection compression ignition (DICI) engine fueled with kerosene-diesel blends, using different piston bowl geometries together with varying injection rate-shapes were investigated. A total of three combustion bowl geometries, namely the omega combustion chamber (OCC), the shallow-depth combustion chamber (SCC) and the shallow-depth re-entrant combustion chamber (SRCC), were used together with six different ramp injection rate-shapes and pure diesel, kerosene-diesel and pure kerosene fuels. It is seen that the SRCC geometry, which has the shortest throat length, gives the highest turbulence kinetic energy (TKE) and this resulted in two peak heat-releases, with a primary peak heat-release during the premixed combustion phase and a secondary peak heat-release during the mixing-controlled combustion phase. In addition, the SCC geometry gives rather distinct premixed combustion and mixing-controlled combustion phases due to the fact that combustion is predominantly controlled by the injected fuel spray itself because of less turbulence. Also, when kerosene is used in place of diesel, the heat-release during the premixed combustion phase increases and diminishes during the mixing-controlled and late combustion phases. It is interesting to note that the effect of injection rate-shaping on the heat-release rate is more obvious for bowl geometries that generate less TKE. Moreover, bowl geometries that generate higher TKEs as well as fuels with lower viscosities generally give lower carbon monoxide (CO) emissions and higher nitrogen oxide (NO) emissions. More importantly, it is possible to achieve low NO and CO emissions simultaneously by using the

  3. Effect of turbo charging and steam injection methods on the performance of a Miller cycle diesel engine (MCDE)

    International Nuclear Information System (INIS)

    Gonca, Guven; Sahin, Bahri

    2017-01-01

    Highlights: • Performance of a diesel engine is simulated by finite time thermodynamics. • Effect of steam injection on performance of a Miller cycle engine is examined. • Model results are verified with the experimental data with less than 7% error. - Abstract: In this study, application of the steam injection method (SIM), Miller cycle (MC) and turbo charging (TC) techniques into a four stroke, direct-injection diesel engine has been numerically and empirically conducted. NOx emissions have detrimental influences on the environment and living beings. They are formed at the high temperatures, thus the Diesel engines are serious NOx generation sources since they have higher compression ratios and higher combustion temperatures. The international regulations have decreased the emission limits due to environmental reasons. The Miller cycle (MC) application and steam injection method (SIM) have been popular to abate NOx produced from the internal combustion engines (ICEs), in the recent years. However, the MC application can cause a reduction in power output. The most known technique which maximizes the engine power and abates exhaust emissions is TC. Therefore, if these three techniques are combined, the power loss can be tolerated and pollutant emissions can be minimized. While the application of the MC and SIM causes to diminish in the brake power and brake thermal efficiency of the engine up to 6.5% and 10%, the TC increases the brake power and brake thermal efficiency of the engine up to 18% and 12%. The experimental and theoretical results have been compared in terms of the torque, the specific fuel consumption (SFC), the brake power and the brake thermal efficiency. The results acquired from theoretical modeling have been validated with empirical data with less than 7% maximum error. The results showed that developed combination can increase the engine performance and the method can be easily applied to the Diesel engines.

  4. Continuous injection rate-shaping for passenger-car diesel engines. Potential, limits and feasibility; Kontinuierliche Einspritzverlaufsformung in Pkw-Dieselmotoren. Potenziale, Grenzen und Realisierungschancen

    Energy Technology Data Exchange (ETDEWEB)

    Predelli, Oliver; Gratzke, Ralf; Sommer, Ansgar; Marohn, Ralf [Ingenieurgesellschaft Auto und Verkehr GmbH, Berlin (Germany); Atzler, Frank; Schuele, Harry; Kastner, Oliver; Nozeran, Nicolas [Continental Automotive GmbH, Regensburg (Germany)

    2010-07-01

    Injection-rate shaping for passenger-car diesel engines is a technique on the verge of a breakthrough. In addition to reducing particulate emission, the method is capable of significantly cutting combustion noise, the Achilles heel of the DI diesel combustion process. As a result, injection-rate shaping shows clear advantages over alternative lowemission combustion processes, such as PCCI, which, although also capable of improving raw emissions in relation to NO{sub x} and soot, are less convincing from the aspect of diesel knock and the emission of CO and CO{sub 2}. Of the modern Common-Rail injection systems, only two permit continuous injection-rate shaping in addition to the hitherto customary strategy of multiple injection. One of them is the Continental PCR NG system. This uses piezo-actuated Common-Rail injectors with direct actuation of the injector nozzle needle. The electronic engine control system provides the capability of determining how far the injector nozzle needle opens. The ability to control the injection curve of each individual injection event gives the engine developer new degrees of freedom in optimizing the combustion process. This paper investigates the way in which the operating behavior of a passenger-car diesel engine is affected by an injection-rate that can be shaped flexibly across broad ranges. Injection-rate shaping aims to use high injection pressures at part load without affecting acoustics and with a view to achieving a significant improvement in emission behavior. The investigation also points out this technique's limits in individual operating points. It furthermore demonstrates approaches suitable for use in mass production with regard to controlling injection-rate shaping in real time in the engine control unit as a way of providing combustion-process stability over the life of the engine. (orig.)

  5. Effect of injection timing and injection pressure on the performance ...

    African Journals Online (AJOL)

    DR OKE

    This paper discusses the feasibility study on the utilization of biodiesel ester of Honge oil (EHO) in common rail direct injection. (CRDI) engine. Biodiesel of EHO has been obtained by transesterification process and characterization has been done. Existing single cylinder diesel engine fitted with conventional mechanical ...

  6. Two-dimensional analysis of two-phase reacting flow in a firing direct-injection diesel engine

    Science.gov (United States)

    Nguyen, H. Lee

    1989-01-01

    The flow field, spray penetration, and combustion in two-stroke diesel engines are described. Fuel injection begins at 345 degrees after top dead center (ATDC) and n-dodecane is used as the liquid fuel. Arrhenius kinetics is used to calculate the reaction rate term in the quasi-global combustion model. When the temperature, fuel, and oxygen mass fraction are within suitable flammability limits, combustion begins spontaneously. No spark is necessary to ignite a localized high temperature region. Compression is sufficient to increase the gaseous phase temperature to a point where spontaneous chemical reactions occur. Results are described for a swirl angle of 22.5 degrees.

  7. Combustion control for diesel engines with direct injection

    Energy Technology Data Exchange (ETDEWEB)

    Jeschke, J.; Henn, M.; Lang, T.; Wendt, J.; Nitzke, H.G.; Mannigel, D. [Volkswagen AG (Germany)

    2007-07-01

    This article looks at a new cylinder pressure-based combustion control for DI diesel engines that has been developed by Volkswagen. This cylinder pressure-based control uses cylinder pressure sensors that are integrated in the glow plugs. The description and the evaluation of these sensors form a main part of this article as they are a central element in the new diesel management system. The test and development phase in connection with a rapid prototyping system and the realisation of the combustion control algorithms in a diesel control unit are also described. Finally, results from use of the closed-loop combustion control with different applications on a diesel engine are presented. (orig.)

  8. Effects of direct injection timing and blending ratio on RCCI combustion with different low reactivity fuels

    International Nuclear Information System (INIS)

    Benajes, Jesús; Molina, Santiago; García, Antonio; Monsalve-Serrano, Javier

    2015-01-01

    Highlights: • E85 requires notable lower premixed energy ratios to achieve a stable combustion. • E10-95 leads to shorter and advanced combustion with higher maximum RoHR peaks. • E20-95, E10-98 and E10-95 reach EURO VI NOx and soot levels for all the engine loads. • E10-95 allows a significant reduction in HC and CO emissions. - Abstract: This work investigates the effects of the direct injection timing and blending ratio on RCCI performance and engine-out emissions at different engine loads using four low reactivity fuels: E10-95, E10-98, E20-95 and E85 (port fuel injected) and keeping constant the same high reactivity fuel: diesel B7 (direct injected). The experiments were conducted using a heavy-duty single-cylinder research diesel engine adapted for dual-fuel operation. All the tests were carried out at 1200 rpm. To assess the blending ratio effect, the total energy delivered to the cylinder coming from the low reactivity fuel was kept constant for the different fuel blends investigated by adjusting the low reactivity fuel mass as required in each case. In addition, a detailed analysis of the air/fuel mixing process has been developed by means of a 1-D in-house developed spray model. Results suggest that notable higher diesel amount is required to achieve a stable combustion using E85. This fact leads to higher NOx levels and unacceptable ringing intensity. By contrast, EURO VI NOx and soot levels are fulfilled with E20-95, E10-98 and E10-95. Finally, the higher reactivity of E10-95 results in a significant reduction in CO and HC emissions, mainly at low load

  9. Effects of piston surface treatments on performance and emissions of a methanol-fueled, direct injection, stratified charge engine

    Energy Technology Data Exchange (ETDEWEB)

    West, B.; Green, J.B. [Oak Ridge National Lab., TN (United States)

    1994-07-01

    The purpose of this study was to investigate the effects of thermal barrier coatings and/or surface treatments on the performance and emissions of a methanol-fueled, direct-injection, stratified-charge (DISC) engine. A Ricardo Hydra Mark III engine was used for this work and in previous experiments at Oak Ridge National Laboratory (ORNL). The primary focus of the study was to examine the effects of various piston insert surface treatments on hydrocarbon (HC) and oxides of nitrogen (NO{sub x}) emissions. Previous studies have shown that engines of this class have a tendency to perform poorly at low loads and have high unburned fuel emissions. A blank aluminum piston was modified to employ removable piston bowl inserts. Four different inserts were tested in the experiment: aluminum, stainless steel with a 1.27-mm (0.050-in.) air gap (to act as a thermal barrier), and two stainless steel/air-gap inserts with coatings. Two stainless steel inserts were dimensionally modified to account for the coating thickness (1.27-mm) and coated identically with partially stabilized zirconia (PSZ). One of the coated inserts then had an additional seal-coat applied. The coated inserts were otherwise identical to the stainless steel/air-gap insert (i.e., they employed the same 1.27-mm air gap). Thermal barrier coatings were employed in an attempt to increase combustion chamber surface temperatures, thereby reducing wall quenching and promoting more complete combustion of the fuel in the quench zone. The seal-coat was applied to the zirconia to reduce the surface porosity; previous research suggested that despite the possibly higher surface temperatures obtainable with a ceramic coating, the high surface area of a plasma-sprayed coating may actually allow fuel to adhere to the surface and increase the unburned fuel emissions and fuel consumption.

  10. Fuel injection system for internal combustion engines. Kraftstoffeinspritzsystem fuer Brennkraftmaschinen

    Energy Technology Data Exchange (ETDEWEB)

    Hafner, U.

    1990-09-13

    A fuel injection system for an internal combustion engine is provided with a fuel supply line (13) and at least one electromagnetically actuated fuel injection valve (14) for apportioning a quantity of fuel for injection. A connection muzzle (24) coming from the valve body (23) juts into an opening (22) in the suction pipe (21) of the internal combustion engine. The end of the injection valve opposite the connecting muzzle (24) is connected with the fuel supply line via a fuel entry. The valve body (23) is enclosed by a casing (25) in order to provide the conditions required for a warm start. An annulus (31) extending over a large part of the axial length of the valve remains between the casing and the valve body (23). The annulus (31) communicates with the fuel flow through the fuel supply line (13) via an afflux and an efflux opening (32, 33) (Fig. 1).

  11. Nanofluidic bubble pump using surface tension directed gas injection

    NARCIS (Netherlands)

    Tas, Niels Roelof; Berenschot, Johan W.; Lammerink, Theodorus S.J.; Elwenspoek, Michael Curt; van den Berg, Albert

    2002-01-01

    A new concept for liquid manipulation has been developed and implemented in surface-micromachined fluid channels. It is based on the surface tension directed injection of a gas into the liquid flow through micrometer-sized holes in the microchannel wall. The injected gas is directed to an exhaust by

  12. An insight on hydrogen fuel injection techniques with SCR system for NO{sub X} reduction in a hydrogen-diesel dual fuel engine

    Energy Technology Data Exchange (ETDEWEB)

    Saravanan, N. [ERC Engines, Hall 11A, Tata Motors, Pimpri, Pune 411019, Maharashtra (India); Nagarajan, G. [Department of Mechanical Engineering, ICE Division, College of Engineering, Guindy, Anna University-Chennai, Chennai 600 025 (India)

    2009-11-15

    Internal combustion engines continue to dominate in many fields like transportation, agriculture and power generation. Among the various alternative fuels, hydrogen is a long-term renewable and less polluting fuel (Produced from renewable energy sources). In the present experimental investigation, the performance and emission characteristics were studied on a direct injection diesel engine in dual fuel mode with hydrogen inducted along with air adopting carburetion, timed port and manifold injection techniques. Results showed that in timed port injection, the specific energy consumption reduces by 15% and smoke level by 18%. The brake thermal efficiency and NO{sub X} increases by 17% and 34% respectively compared to baseline diesel. The variation in performance between port and manifold injection is not significant. The unburnt hydrocarbons and carbon monoxide emissions are lesser in port injection. The oxides of nitrogen are higher in hydrogen operation (both port and manifold injection) compared to diesel engine. In order to reduce the NO{sub X} emissions, a selective catalytic converter was used in hydrogen port fuel injection. The NO{sub X} emission reduced upto a maximum of 74% for ANR (ratio of flow rate of ammonia to the flow rate of NO) of 1.1 with a marginal reduction in efficiency. Selective catalytic reduction technique has been found to be effective in reducing the NO{sub X} emission from hydrogen fueled diesel engines. (author)

  13. COMBUSTION HEAT RELEASE RATE ANALYSIS OF C.I. ENGINE WITH SECONDARY CO-INJECTION OF DEE-H2O SOLUTION - A VIBRATIONAL APPROACH

    Directory of Open Access Journals (Sweden)

    Y. V. V. SATYANARAYANA MURTHY

    2015-08-01

    Full Text Available This paper discusses the combustion propensity of single cylinder direct injection engine fueled with palm kernel methyl ester (PKME, which is non- edible oil and a secondary co-injection of saturated Diethyl ether (DEE with water. DEE along with water is fumigated through a high pressure nozzle fitted to the inlet manifold of the engine and the flow rate of the secondary injection was electronically controlled. DEE is known to improve the cold starting problem in engines when used in straight diesel fuel. However, its application in emulsion form is little known. Experimental results show that for 5% DEE- H2O solution injection, occurrence of maximum net heat release rate is delayed due to controlled premixed combustion, which normally helped in better torque conversion when the piston is in accelerated mode. Vibration measurements in the frequency range of 900Hz to 1300Hz revealed that a new mode of combustion has taken place with different excitation frequencies.

  14. 76 FR 8661 - Airworthiness Directives; Lycoming Engines, Fuel Injected Reciprocating Engines

    Science.gov (United States)

    2011-02-15

    ... . Follow the instructions for submitting comments. Fax: 202-493-2251. Mail: U.S. Department of... after receipt. FOR FURTHER INFORMATION CONTACT: Norm Perenson, Aerospace Engineer, New York Aircraft... MSB 342B, MSB 342A, and MSB 342. [[Page 8662

  15. Optical diagnostics of early flame development in a DISI (direct injection spark ignition) engine fueled with n-butanol and gasoline

    International Nuclear Information System (INIS)

    Merola, Simona Silvia; Tornatore, Cinzia; Irimescu, Adrian; Marchitto, Luca; Valentino, Gerardo

    2016-01-01

    Given the instability in supply and finite nature of fossil fuels, alternative renewable energy sources are continuously investigated throughout the production–distribution-use chain. Within this context, the research presented in this work is focused on using butanol as gasoline replacement in a Direct Injection Spark Ignition engine. The impact of this fuel on the combustion processes was investigated using optical diagnostics and conventional methods in a transparent single cylinder engine. Three different load settings were investigated at fixed engine speed, with combined throttling and mixture strength control. The engine was operated in homogenous charge mode, with commercial gasoline and pure n-butanol fueling. High spatial and temporal resolution visualization was applied in the first phase of the combustion process in order to follow the early flame development for the two fuels. The optical data were completed with conventional measurements of thermodynamic data and pollutants emission at the exhaust. Improved performance was obtained in throttled stoichiometric mode when using the alternative fuel, while at wide open throttle, gasoline featured higher indicated mean effective pressure at both air–fuel ratio settings. These overall findings were correlated to flame characteristics; the alcohol was found to feature more distorted flame contour compared to gasoline, especially in lean conditions. Differences were reduced during throttled stoichiometric operation, confirming that mass transfer processes, along with fuel chemistry and physical properties, exert a significant influence on local phenomena during combustion. - Highlights: • Butanol can replace gasoline without performance penalties in throttled, stoichiometric operation. • Butanol induces higher flame contour distortion than gasoline, especially in lean case. • Fuel chemical–physical properties strongly influence local phenomena during combustion. • Butanol ensured lower smoke

  16. Influence of Advanced Injection Timing and Fuel Additive on Combustion, Performance, and Emission Characteristics of a DI Diesel Engine Running on Plastic Pyrolysis Oil

    Directory of Open Access Journals (Sweden)

    Ioannis Kalargaris

    2017-01-01

    Full Text Available This paper presents the investigation of engine optimisation when plastic pyrolysis oil (PPO is used as the primary fuel of a direct injection diesel engine. Our previous investigation revealed that PPO is a promising fuel; however the results suggested that control parameters should be optimised in order to obtain a better engine performance. In the present work, the injection timing was advanced, and fuel additives were utilised to overcome the issues experienced in the previous work. In addition, spray characteristics of PPO were investigated in comparison with diesel to provide in-depth understanding of the engine behaviour. The experimental results on advanced injection timing (AIT showed reduced brake thermal efficiency and increased carbon monoxide, unburned hydrocarbons, and nitrogen oxides emissions in comparison to standard injection timing. On the other hand, the addition of fuel additive resulted in higher engine efficiency and lower exhaust emissions. Finally, the spray tests revealed that the spray tip penetration for PPO is faster than diesel. The results suggested that AIT is not a preferable option while fuel additive is a promising solution for long-term use of PPO in diesel engines.

  17. Study on a small diesel engine with direct injection impinging distribution spray combustion system. Optimum of injection system and combustion chamber; Shototsu kakusan hoshiki kogata diesel kikan ni kansuru kenkyu. Funshakei to nenshoshitsu no saitekika

    Energy Technology Data Exchange (ETDEWEB)

    Fujita, K; Kato, S; Saito, T [Kanazawa Institute of Technology, Ishikawa (Japan); Tanabe, H [Gunma University, Gunma (Japan)

    1997-10-01

    This study is concerned with a small bore (93mm) diesel engine using impinged fuel spray, named OSKA system. The higher rate of injection show lower smoke emission with higher NOx Emission. The exhaust emission and performance were investigated under different compression ratio with higher rate of injection. The experimental results show that this OSKA system is capable for reducing the smoke emission without the deterioration of NOx emission and fuel consumption compared with the conventional DI diesel engine. 5 refs., 8 figs., 3 tabs.

  18. Quantitative characterization of near-field fuel sprays by multi-orifice direct injection using ultrafast x-tomography technique

    International Nuclear Information System (INIS)

    Liu, X.; Im, K.S.; Wang, Y.; Wang, J.; Hung, D.L.S.; Winkelman, J.R.; Tate, M.W.; Ercan, A.; Koerner, L.J.; Caswell, T.; Chamberlain, D.; Schuette, D.R.; Philipp, H.; Smilgies, D.M.; Gruner, S.M.

    2006-01-01

    A low-pressure direct injection fuel system for spark ignition direct injection engines has been developed, in which a high-turbulence nozzle technology was employed to achieve fine fuel droplet size at a low injection pressure around 2 MPa. It is particularly important to study spray characteristics in the near-nozzle region due to the immediate liquid breakup at the nozzle exit. By using an ultrafast x-ray area detector and intense synchrotron x-ray beams, the interior structure and dynamics of the direct injection gasoline sprays from a multi-orifice turbulence-assisted nozzle were elucidated for the first time in a highly quantitative manner with μs-temporal resolution. Revealed by a newly developed, ultrafast computed x-microtomography technique, many detailed features associated with the transient liquid flows are readily observable in the reconstructed spray. Furthermore, an accurate 3-dimensional fuel density distribution, in the form of fuel volume fraction, was obtained by the time-resolved computed tomography. The time-dependent fuel density distribution revealed that the fuel jet is well broken up immediately at the nozzle exits. These results not only reveal the near-field characteristics of the partial atomized fuel sprays with unprecedented detail, but also facilitate the development of an advanced multi-orifice direct injector. This ultrafast tomography capability also will facilitate the realistic computational fluid dynamic simulations in highly transient and multiphase fuel spray systems.

  19. Optimal calibration of variable biofuel blend dual-injection engines using sparse Bayesian extreme learning machine and metaheuristic optimization

    International Nuclear Information System (INIS)

    Wong, Ka In; Wong, Pak Kin

    2017-01-01

    Highlights: • A new calibration method is proposed for dual-injection engines under biofuel blends. • Sparse Bayesian extreme learning machine and flower pollination algorithm are employed in the proposed method. • An SI engine is retrofitted for operating under dual-injection strategy. • The proposed method is verified experimentally under the two idle speed conditions. • Comparison with other machine learning methods and optimization algorithms is conducted. - Abstract: Although many combinations of biofuel blends are available in the market, it is more beneficial to vary the ratio of biofuel blends at different engine operating conditions for optimal engine performance. Dual-injection engines have the potential to implement such function. However, while optimal engine calibration is critical for achieving high performance, the use of two injection systems, together with other modern engine technologies, leads the calibration of the dual-injection engines to a very complicated task. Traditional trial-and-error-based calibration approach can no longer be adopted as it would be time-, fuel- and labor-consuming. Therefore, a new and fast calibration method based on sparse Bayesian extreme learning machine (SBELM) and metaheuristic optimization is proposed to optimize the dual-injection engines operating with biofuels. A dual-injection spark-ignition engine fueled with ethanol and gasoline is employed for demonstration purpose. The engine response for various parameters is firstly acquired, and an engine model is then constructed using SBELM. With the engine model, the optimal engine settings are determined based on recently proposed metaheuristic optimization methods. Experimental results validate the optimal settings obtained with the proposed methodology, indicating that the use of machine learning and metaheuristic optimization for dual-injection engine calibration is effective and promising.

  20. Numerical Study on the Performance Characteristics of Hydrogen Fueled Port Injection Internal Combustion Engine

    OpenAIRE

    Rosli A. Bakar; Mohammed K. Mohammed; M. M. Rahman

    2009-01-01

    This study was focused on the engine performance of single cylinder hydrogen fueled port injection internal combustion engine. GT-Power was utilized to develop the model for port injection engine. One dimensional gas dynamics was represented the flow and heat transfer in the components of the engine model. The governing equations were introduced first, followed by the performance parameters and model description. Air-fuel ratio was varied from stoichiometric limit to a lean limit and the rota...

  1. Atomization and spray characteristics of bioethanol and bioethanol blended gasoline fuel injected through a direct injection gasoline injector

    International Nuclear Information System (INIS)

    Park, Su Han; Kim, Hyung Jun; Suh, Hyun Kyu; Lee, Chang Sik

    2009-01-01

    The focus of this study was to investigate the spray characteristics and atomization performance of gasoline fuel (G100), bioethanol fuel (E100), and bioethanol blended gasoline fuel (E85) in a direct injection gasoline injector in a gasoline engine. The overall spray and atomization characteristics such as an axial spray tip penetration, spray width, and overall SMD were measured experimentally and predicted by using KIVA-3V code. The development process and the appearance timing of the vortices in the test fuels were very similar. In addition, the numerical results accurately described the experimentally observed spray development pattern and shape, the beginning position of the vortex, and the spray breakup on the spray surface. Moreover, the increased injection pressure induced the occurrence of a clear circular shape in the downstream spray and a uniform mixture between the injected spray droplets and ambient air. The axial spray tip penetrations of the test fuels were similar, while the spray width and spray cone angle of E100 were slightly larger than the other fuels. In terms of atomization performance, the E100 fuel among the tested fuels had the largest droplet size because E100 has a high kinematic viscosity and surface tension.

  2. CFD Modeling of Fuel Injection and Combustion in an HDDI Engine

    Energy Technology Data Exchange (ETDEWEB)

    Rijk, E.

    2009-07-01

    In this study, the Star-CD CFD package is first used to model spray formation in a constant volume chamber and in a cycle of a heavy duty direct injection (HDDI) engine. Secondly, combustion is modeled using a standard Star-CD combustion model and a user-defined tabulated chemistry method (FGM). In modern diesel engines, fuel is injected into the combustion chamber by an injector, at a high pressure. As the fuel flows through this nozzle, phenomena like cavitation can occur influencing the injection velocity. When the liquid fuel jet exits the nozzle, it breaks up into droplets, which is called primary break-up. Due to the velocity difference between the in-cylinder air and these droplets, they break-up even further, called secondary break-up. The high temperature in the combustion chamber make the droplets evaporate until a point is reached where no liquid fuel is present anymore (liquid length). Hereafter, the evaporated fuel penetrates further (fuel penetration) and at some point in time, the spray auto-ignites. In Star-CD, different sub-models are present to simulate nozzle flow, primary and secondary break-up in a Eulerian-Lagrangian framework. The best performing sub-models are determined by comparing measured liquid length and fuel penetration with calculated values. To be able to do this objectively, a virtual Mie scattering method is developed and applied, together with a previously designed virtual Schlieren method. Using this optimal combination of sub-models, a sensitivity study is performed as previous research revealed that CFD calculations can be highly mesh and timestep dependent. When the optimal settings are known, the Star-CD spray results are validated with experimental data containing a wide range of nozzle diameters, ambient conditions, injection pressures and fuel types. Next to Star-CD, non-Lagrangian models are used to calculate liquid length and spray penetration. It appears that the accuracies of Star-CD and the non-Lagrangian model of

  3. Emission Constrained Multiple-Pulse Fuel Injection Optimisation and Control for Fuel-Efficient Diesel Engines

    NARCIS (Netherlands)

    Luo, X.; Jager, B. de; Willems, F.P.T.

    2015-01-01

    With the application of multiple-pulse fuel injection profiles, the performance of diesel engines is enhanced in terms of low fuel consumption and low engine-out emission levels. However, the calibration effort increases due to a larger number of injection timing parameters. The difficulty of

  4. Flex-Fuel Two-Stroke Snowmobile: Development of a Flex-Fuel, Two-Stroke, Direct-Injection Snowmobile for Use in the Clean Snowmobile Challenge and National Parks

    Science.gov (United States)

    2009-09-01

    The University of Idaho's entry into the 2009 SAE Clean Snowmobile Challenge (CSC) was a semi-direct-injection (SDI) two-stroke powered REV-XP snowmobile modified to use flex fuel. The flex fuel engine produces stock engine power on any blend of etha...

  5. Effect of advanced injection timing on emission characteristics of diesel engine running on natural gas

    Energy Technology Data Exchange (ETDEWEB)

    Nwafor, O.M.I. [Department of Mechanical Engineering, Federal University of Technology, Owerri, Imo State (Nigeria)

    2007-11-15

    There has been a growing concern on the emission of greenhouse gases into the atmosphere, whose consequence is global warming. The sources of greenhouse gases have been identified, of which the major contributor is the combustion of fossil fuel. Researchers have intensified efforts towards identifying greener alternative fuel substitutes for the present fossil fuel. Natural gas is now being investigated as potential alternative fuel for diesel engines. Natural gas appears more attractive due to its high octane number and perhaps, due to its environmental friendly nature. The test results showed that alternative fuels exhibit longer ignition delay, with slow burning rates. Longer delays will lead to unacceptable rates of pressure rise with the result of diesel knock. This work examines the effect of advanced injection timing on the emission characteristics of dual-fuel engine. The engine has standard injection timing of 30 BTDC. The injection was first advanced by 5.5 and given injection timing of 35.5 BTDC. The engine performance was erratic on this timing. The injection was then advanced by 3.5 . The engine performance was smooth on this timing especially at low loading conditions. The ignition delay was reduced through advanced injection timing but tended to incur a slight increase in fuel consumption. The CO and CO{sub 2} emissions were reduced through advanced injection timing. (author)

  6. Spray and evaporation characteristics of ethanol and gasoline direct injection in non-evaporating, transition and flash-boiling conditions

    International Nuclear Information System (INIS)

    Huang, Yuhan; Huang, Sheng; Huang, Ronghua; Hong, Guang

    2016-01-01

    Highlights: • Sprays can be considered as non-evaporating when vapour pressure is lower than 30 kPa. • Ethanol direct injection should only be applied in high temperature engine environment. • Gasoline spray collapses at lower fuel temperature (350 K) than ethanol spray does (360 K). • Flash-boiling does not occur when fuel temperature reaches boiling point until ΔT is 14 K. • Not only spray evaporation mode but also breakup mechanism change with fuel temperature. - Abstract: Ethanol direct injection plus gasoline port injection (EDI + GPI) represents a more efficient and flexible way to utilize ethanol fuel in spark ignition engines. To exploit the potentials of EDI, the mixture formation characteristics need to be investigated. In this study, the spray and evaporation characteristics of ethanol and gasoline fuels injected from a multi-hole injector were investigated by high speed Shadowgraphy imaging technique in a constant volume chamber. The experiments covered a wide range of fuel temperature from 275 K (non-evaporating) to 400 K (flash-boiling) which corresponded to cold start and running conditions in an engine. The spray transition process from normal-evaporating to flash-boiling was investigated in greater details than the existed studies. Results showed that ethanol and gasoline sprays demonstrated the same patterns in non-evaporating conditions. The sprays could be considered as non-evaporating when vapour pressure was lower than 30 kPa. Ethanol evaporated more slowly than gasoline did in low temperature environment, but they reached the similar evaporation rates when temperature was higher than 375 K. This suggested that EDI should only be applied in high temperature engine environment. For both ethanol and gasoline sprays, when the excess temperature was smaller than 4 K, the sprays behaved the same as the subcooled sprays did. The sprays collapsed when the excess temperature was 9 K. Flash-boiling did not occur until the excess temperature

  7. Effect of cavitation in high-pressure direct injection

    Science.gov (United States)

    Aboulhasanzadeh, Bahman; Johnsen, Eric

    2015-11-01

    As we move toward higher pressures for Gasoline Direct Injection and Diesel Direct Injection, cavitation has become an important issue. To better understand the effect of cavitation on the nozzle flow and primary atomization, we use a high-order accurate Discontinuous Galerkin approach using multi-GPU parallelism to simulate the compressible flow inside and outside the nozzle. Phase change is included using the six-equations model. We investigate the effect of nozzle geometry on cavitation inside the injector and on primary atomization outside the nozzle.

  8. Effect of injection pressure on heat release rate and emissions in CI engine using orange skin powder diesel solution

    International Nuclear Information System (INIS)

    Purushothaman, K.; Nagarajan, G.

    2009-01-01

    Experiments have been conducted to study the effect of injection pressure on the combustion process and exhaust emissions of a direct injection diesel engine fueled with Orange Skin Powder Diesel Solution (OSPDS). Earlier investigation by the authors revealed that 30% OSPDS was optimum for better performance and emissions. In the present investigation the injection pressure was varied with 30% OSPDS and the combustion, performance and emissions characteristics were compared with those of diesel fuel. The different injection pressures studied were 215 bar, 235 bar and 255 bar. The results showed that the cylinder pressure with 30% OSPDS at 235 bar fuel injection pressure, was higher than that of diesel fuel as well as at other injection pressures. Similarly, the ignition delay was longer and with shorter combustion duration with 30% OSPDS at 235 bar injection pressure. The brake thermal efficiency was better at 235 bar than that of other fuel injection pressures with OSPDS and lower than that of diesel fuel. The NO x emission with 30% OSPDS was higher at 235 bar. The hydrocarbon and CO emissions were lower with 30% OSPDS at 235 bar. The smoke emission with 30% OSPDS was marginally lower at 235 bar and marginally higher at 215 bar than for diesel fuel. The combustion, performance and emission characteristics of the engine operating on the test fuels at 235 bar injection pressure were better than other injection pressures

  9. Analysis the effect of advanced injection strategies on engine performance and pollutant emissions in a heavy duty DI-diesel engine by CFD modeling

    International Nuclear Information System (INIS)

    Mobasheri, Raouf; Peng, Zhijun; Mirsalim, Seyed Mostafa

    2012-01-01

    Highlights: ► Explore the effects of advanced multiple injection strategies in a DI-diesel engine. ► Achieving good agreement between the predicted results and experimental values. ► Analyzing three factors for optimization including pilot, main and post-injection. ► Injecting adequate fuel in each pulse accompanied with an appropriate EGR rate. ► Beneficial effects for significant soot reduction without a NOx penalty rate. - Abstract: An Advanced CFD simulation has been carried out in order to explore the combined effects of pilot-, post- and multiple-fuel injection strategies and EGR on engine performance and emission formation in a heavy duty DI-diesel engine. An improved version of the ECFM-3Z combustion model has been applied coupled with advanced models for NOx and soot formation. The model was validated with experimental data achieved from a Caterpillar 3401 DI diesel engine and good agreement between predicted and measured in-cylinder pressure, heat release rate, NOx and soot emissions was obtained. The optimizations were conducted separately for different split injection cases without pilot injection and then, for various multiple injection cases. Totally, three factors were considered for the injection optimization, which included EGR rate, the separation between main injection and post-injection and the amount of injected fuel in each pulse. For the multiple injection cases, two more factors (including double and triple injections during main injection) were also added. Results show that using pilot injection accompanied with an optimized main injection has a significant beneficial effect on combustion process so that it could form a separate 2nd stage of heat release which could reduce the maximum combustion temperature, which leads to the reduction of the NOx formation. In addition, it has found that injecting adequate fuel in post-injection at an appropriate EGR allows significant soot reduction without a NOx penalty rate.

  10. Gasoline engine management systems and components

    CERN Document Server

    2015-01-01

    The call for environmentally compatible and economical vehicles necessitates immense efforts to develop innovative engine concepts. Technical concepts such as gasoline direct injection helped to save fuel up to 20 % and reduce CO2-emissions. Descriptions of the cylinder-charge control, fuel injection, ignition and catalytic emission-control systems provides comprehensive overview of today´s gasoline engines. This book also describes emission-control systems and explains the diagnostic systems. The publication provides information on engine-management-systems and emission-control regulations. Contents History of the automobile.- Basics of the gasoline engine.- Fuels.- Cylinder-charge control systems.- Gasoline injection systems over the years.- Fuel supply.- Manifold fuel injection.- Gasoline direct injection.- Operation of gasoline engines on natural gas.- Ignition systems over the years.- Inductive ignition systems.- Ignition coils.- Spark plugs.- Electronic control.- Sensors.- Electronic control unit.- Exh...

  11. Separate direct injection of diesel and ethanol: A numerical analysis

    Directory of Open Access Journals (Sweden)

    Burnete Nicolae V.

    2017-01-01

    Full Text Available The purpose of this study is to investigate the theoretical possibility of using a pilot diesel injection for the auto-ignition of a main ethanol injection in a compression ignition engine. To this effect a predictive simulation model has been built based on experimental results for a diesel cycle (pilot and main injection at 1500 and 2500 min–1, respectively. For every engine speed, in addition to the diesel reference cycle, two more simulations were done: one with the same amount of fuel injected into the cylinder and one with the same amount of energy, which required an increase in the quantity of ethanol proportional to the ratio of its lower heating value and that of diesel. The simulations showed that in all cases the pilot diesel led to the auto-ignition of ethanol. The analysis of the in-cylinder traces at 1500 min–1 showed that combustion efficiency is improved, the peak temperature value decrease with approximately 240 K and, as a result, the NO emissions are 3.5-4 times lower. The CO and CO2 values depend on the amount of fuel injected into the cylinder. At 2500 min–1 there are similar trends but with the following observations: the ignition delay increases, while the pressure and temperature are lower.

  12. Experimental investigation of the concomitant injection of gasoline and CNG in a turbocharged spark ignition engine

    International Nuclear Information System (INIS)

    Momeni Movahed, M.; Basirat Tabrizi, H.; Mirsalim, M.

    2014-01-01

    Highlights: • Concomitant injection of gasoline and CNG is compared with gasoline and CNG modes. • BSFC, HC and CO emissions of the concomitant injection are lower than gasoline mode. • Deteriorations of the concomitant injection are negligible compared to gasoline mode. • Cylinder peak pressure and heat loss to coolant of the concomitant injection are lower than CNG mode. • Some shortcomings in CNG mode can be solved by changing the spark timing and lambda. - Abstract: Concomitant injection of gasoline and CNG is a new concept to overcome problems of bi-fueled spark ignition engines, which operate in single fuel mode, either in gasoline or in CNG mode. This experimental study indicates how some problems of gasoline mode such as retarded ignition timings for knock prevention and rich air–fuel mixture for component protection can be resolved with the concomitant injection of gasoline and CNG. Results clearly show that the concomitant injection improves thermal efficiency compared to gasoline mode. On the other hand, simultaneous injection of gasoline and CNG reduces some problems of CNG mode such as high cylinder pressure and heat loss to the engine coolant. This decreases the stringent requirements for thermal and mechanical strength of the engine components in CNG mode. In addition, it is shown that by modifying the spark advance and air fuel ratio in CNG mode, the engine operation improves in terms of NOx emissions and maximum in-cylinder pressure as the concomitant injection does. Nevertheless, new requirements such as an intercooler with higher cooling capacity are implied to the engine configuration. Finally, the most important concerns in control strategies of the engine control unit for a vehicle with concomitant injection of gasoline and CNG are discussed

  13. Thermodynamic analysis of EGR effects on the first and second law efficiencies of a boosted spark-ignited direct-injection gasoline engine

    International Nuclear Information System (INIS)

    Li, Tie; Wu, Da; Xu, Min

    2013-01-01

    Highlights: • We clarified the mechanism of EGR improving fuel economy of gasoline engines. • At constant air–fuel ratio, reduction of heat transfer loss is most significant. • At full load, elimination of fuel enrichment is dominant. • Combustion irreversibility increases with EGR. • Availability in the exhaust and heat transfer losses is smaller than energy losses. - Abstract: Exhaust gas recirculation (EGR) is effective to improve fuel economy of spark-ignition gasoline engines, but the detailed mechanism needs to be further investigated. In this paper, an in-depth analysis of the effects of cooled EGR on the fuel conversion efficiency of a boosted, spark-ignited, direct-injection, gasoline engines operated at the full, medium and low loads is conducted with the engine experiment and 1-D cycle simulation based on the first and second laws of thermodynamics. For all the operating loads, EGR increases the ratio of specific heat of working gas, reduces the fraction of heat transfer through the combustion chamber walls, and improves the pumping work during the gas exchanging stroke. Besides, EGR may replace the fuel enrichment at high load, advance the combustion phasing and increase the degree of constant volume heat release at the medium and high loads. As a result, about 1.1–4.1% improvements in the brake thermal efficiency are obtained by the 12–17% EGR at different loads. Despite the increased fraction of combustion-generated irreversibility (destruction in availability or exergy), the fraction of indicated work in the total availability increases with EGR for all the operating loads. Among the influencing factors, the effect of reduction in the heat transfer loss owing to EGR is dominant in improvement of the fuel conversion efficiency at constant air–fuel ratio, while replacement of the fuel enrichment with EGR is most effective at full load

  14. Application of macro-cellular SiC reactor to diesel engine-like injection and combustion conditions

    Science.gov (United States)

    Cypris, Weclas, M.; Greil, P.; Schlier, L. M.; Travitzky, N.; Zhang, W.

    2012-05-01

    One of novel combustion technologies for low emissions and highly efficient internal combustion engines is combustion in porous reactors (PM). The heat release process inside combustion reactor is homogeneous and flameless resulting in a nearly zero emissions level. Such combustion process, however is non-stationary, is performed under high pressure with requirement of mixture formation directly inside the combustion reactor (high pressure fuel injection). Reactor heat capacity resulting in lowering of combustion temperature as well as internal heat recuperation during the engine cycle changes the thermodynamic conditions of the process as compared to conventional engine. For the present investigations a macro-cellular lattice structure based on silicon carbide (non-foam structure) with 600 vertical cylindrical struts was fabricated and applied to engine-like combustion conditions (combustion chamber). The lattice design with a high porosity > 80% was shaped by indirect three-dimensional printing of a SiC powder mixed with a dextrin binder which also serves as a carbon precursor. In order to perform detailed investigations on low-and high-temperature oxidation processes in porous reactors under engine-like conditions, a special combustion chamber has been built and equipped with a Diesel common-rail injection system. This system simulates the thermodynamic conditions at the time instance of injection onset (corresponding to the nearly TDC of compression in a real engine). Overall analysis of oxidation processes (for variable initial pressure, temperature and air excess ratio) for free Diesel spray combustion and for combustion in porous reactor allows selection of three regions representing different characteristics of the oxidation process represented by a single-step and multi-step reactions Another characteristic feature of investigated processes is reaction delay time. There are five characteristic regions to be selected according to the delay time (t) duration

  15. 78 FR 5710 - Airworthiness Directives; Engine Alliance Turbofan Engines

    Science.gov (United States)

    2013-01-28

    ... Airworthiness Directives; Engine Alliance Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT... all Engine Alliance GP7270 and GP7277 turbofan engines. This AD requires initial and repetitive...) Applicability This AD applies to all Engine Alliance GP7270 and GP7277 turbofan engines with a high-pressure...

  16. DIAGNOSTICS OF GASOLINE FUEL SYSTEMS WITH DIRECT INJECTION

    Directory of Open Access Journals (Sweden)

    M. Bulgakov

    2017-11-01

    Full Text Available A method of diagnosing fuel systems with direct injection by means of producing a pressure oscillation in a hydraulic accumulator is presented. Having obtained a signal from pressure sensor it is possible to register a pressure drop at the moment of injection. If the system has a malfunction, then the pressure drop will be higher.

  17. The new 1.8-litre 4-cylinder petrol engine with direct injection and turbocharging for all passenger cars with standard drivetrains from Mercedes-Benz; Der neue 1,81 4-Zylinder Turbo-Direkteinspritz-Ottomotor fuer alle PKW mit Standardantrieb von Mercedes-Benz

    Energy Technology Data Exchange (ETDEWEB)

    Lueckert, Peter; Kreitmann, Fritz; Merdes, Norbert; Weller, Ralph; Rehberger, Andreas; Bruchner, Klaus; Schwedler, Klaus; Ottenbacher, Hermann; Keller, Thomas [Daimler AG, Stuttgart (Germany)

    2009-07-01

    In the past years, the 4-cylinder gasoline engine from Mercedes-Benz (Stuttgart, Federal Republic of Germany) with the internal designation M 271 worked in the best way in the vehicles of the C, E and SLK class. The 4-cylinder engine M 271 evo introduced here represents the consistent advancement for many years of downsizing concepts in series. The emphasis was the conversion of consumption-reducing measures. At the same time also the power ratings and torque values were increased. Substantial properties of change are the conversion of the suction tube channel injection to a homogeneous direct injection procedure as well as the disappearance of the compressor and the substitution by a single-step Wastegate supercharger. The configuration of the basic engine with 1.8 L capacity was maintained. Thus, in opposite to the precursor engine a distinct improvement in the fuel consumption could be achieved in the balance.

  18. Injection system used into SI engines for complete combustion and reduction of exhaust emissions in the case of alcohol and petrol alcohol mixtures feed

    Science.gov (United States)

    Ispas, N.; Cofaru, C.; Aleonte, M.

    2017-10-01

    Internal combustion engines still play a major role in today transportation but increasing the fuel efficiency and decreasing chemical emissions remain a great goal of the researchers. Direct injection and air assisted injection system can improve combustion and can reduce the concentration of the exhaust gas pollutes. Advanced air-to-fuel and combustion air-to-fuel injection system for mixtures, derivatives and alcohol gasoline blends represent a major asset in reducing pollutant emissions and controlling combustion processes in spark-ignition engines. The use of these biofuel and biofuel blending systems for gasoline results in better control of spark ignition engine processes, making combustion as complete as possible, as well as lower levels of concentrations of pollutants in exhaust gases. The main purpose of this paper was to provide most suitable tools for ensure the proven increase in the efficiency of spark ignition engines, making them more environmentally friendly. The conclusions of the paper allow to highlight the paths leading to a better use of alcohols (biofuels) in internal combustion engines of modern transport units.

  19. Two-stroke engine with gaseous and liquid fuel injection

    Energy Technology Data Exchange (ETDEWEB)

    Laursen, Rene Sejer [MAN Diesel and Turbo SE, Copenhagen (Denmark)

    2012-08-15

    The need to lower emissions of CO{sub 2}, NO{sub x}, SO{sub x} and particulates as well as rising oil prices have increased engine operators' interest in alternative fuels and fuel flexibility. The low speed two-stroke ME-GI and ME-LGI dual-fuel engines with diesel pilot injection from MAN Diesel and Turbo offer the opportunity of utilising fuels such as LNG, LPG, and methanol in a wide range of liquid to gaseous fuel ratios. (orig.)

  20. Effect of diesel pre-injection timing on combustion and emission characteristics of compression ignited natural gas engine

    International Nuclear Information System (INIS)

    Xu, Min; Cheng, Wei; Zhang, Hongfei; An, Tao; Zhang, Shaohua

    2016-01-01

    Highlights: • Pre-injection timing on combustion and emission of CING engine are studied. • Closely pre-injection operations leads to increase of combustion intensity. • Early pre-injection operations leads to lower combustion intensity. • Early pre-injection modes provide better NO x emission. - Abstract: Pre-injection strategy is considered to be one of the most important ways to improve diesel engine performance, emission and combustion. It is the same important factor in pilot diesel compression ignition natural gas (CING) engine. In this study, effects of pre-injection timing on combustion and emission performances were experimentally studied in a CING engine which was modified from a turbocharged six-cylinder diesel engine. The experiments were conducted at constant speed of 1400 rpm and different engine loads with a constant fuel injection pressure of 1100 bar. Main injection timing was fixed at 10 °CA BTDC in the advance process of pre-injection timing. The cylinder pressure, heart release rate (HRR), pressure rise rate (PRR), start of combustion (SOC) and coefficient of variation (COV IMEP ), as well as NO x , HC and CO emissions were analyzed. The results indicated that closely pre-injection operations lead to the advance of SOC which intensified combustion of in-cylinder mixture, thereby resulting in higher cylinder pressure, HRR and PRR, as well higher NO x emissions and lower HC and CO emissions. However, early pre-injection operations lead to lower cylinder pressure, HRR and PRR due to decreasing in combustion intensity. Pre-injection timing of 70 °CA BTDC is a conversion point in which influence of pre-injection fuel on ignition and combustion of natural gas nearly disappeared and lowest NO x emission could be obtained. Compared with single injection ignition mode, NO x emissions at the conversion point were reduced by 33%, 38% and 7% at engine load of 38%, 60% and 80% respectively. This is important for the conditions that ignition fuel

  1. Influence of injection timing on performance, combustion and emission characteristics of Jatropha biodiesel engine

    International Nuclear Information System (INIS)

    Ganapathy, T.; Gakkhar, R.P.; Murugesan, K.

    2011-01-01

    Highlights: → The effect of injection timing, load and speed on BSFC, BTE, peak pressure, HRR, CO, HC, NO and smoke were investigated. → Advanced injection timing caused reduced BSFC, CO, HC, smoke and increased BTE, P max , HRR max and NO for Jatropha biodiesel. → At 15 N m, 1800 rpm and 340 CAD, reduction in BSFC, CO, HC and smoke were 5.1%, 2.5%, 1.2% and 1.5% for Jatropha biodiesel. → Increase in BTE, P max , HRR max and NO at 15 N m, 1800 rpm and 340 CAD were 5.3%, 1.8%, 26% and 20% for Jatropha biodiesel. → Optimal injection timing for Jatropha biodiesel with minimum BSFC, CO, HC, smoke and maximum BTE, P max , HRR is 340 CAD. -- Abstract: The study of effect of injection timing along with engine operating parameters in Jatropha biodiesel engine is important as they significantly affect its performance and emissions. The present paper focuses on the experimental investigation of the influence of injection timing, load torque and engine speed on the performance, combustion and emission characteristics of Jatropha biodiesel engine. For this purpose, the experiments were conducted using full factorial design consisting of (3 3 ) with 27 runs for each fuel, diesel and Jatropha biodiesel. The effect of variation of above three parameters on brake specific fuel consumption (BSFC), brake thermal efficiency (BTE), peak cylinder pressure (P max ), maximum heat release rate (HRR max ), CO, HC, NO emissions and smoke density were investigated. It has been observed that advance in injection timing from factory settings caused reduction in BSFC, CO, HC and smoke levels and increase in BTE, P max , HRR max and NO emission with Jatropha biodiesel operation. However, retarded injection timing caused effects in the other way. At 15 N m load torque, 1800 rpm engine speed and 340 crank angle degree (CAD) injection timing, the percentage reduction in BSFC, CO, HC and smoke levels were 5.1%, 2.5%, 1.2% and 1.5% respectively. Similarly the percentage increase in BTE, P

  2. Size distribution, chemical composition and oxidation reactivity of particulate matter from gasoline direct injection (GDI) engine fueled with ethanol-gasoline fuel

    International Nuclear Information System (INIS)

    Luo, Yueqi; Zhu, Lei; Fang, Junhua; Zhuang, Zhuyue; Guan, Chun; Xia, Chen; Xie, Xiaomin; Huang, Zhen

    2015-01-01

    Ethanol-gasoline blended fuels have been widely applied in markets recently, as ethanol reduces life-cycle greenhouse gas emissions and improves anti-knock performance. However, its effects on particulate matter (PM) emissions from gasoline direct injection (GDI) engine still need further investigation. In this study, the effects of ethanol-gasoline blended fuels on particle size distributions, number concentrations, chemical composition and soot oxidation activity of GDI engine were investigated. It was found that ethanol-gasoline blended fuels increased the particle number concentration in low-load operating conditions. In higher load conditions, the ethanol-gasoline was effective for reducing the particle number concentration, indicating that the chemical benefits of ethanol become dominant, which could reduce soot precursors such as large n-alkanes and aromatics in gasoline. The volatile organic mass fraction in ethanol-gasoline particulates matter was higher than that in gasoline particulate matter because ethanol reduced the amount of soot precursors during combustion and thereby reduced the elemental carbon proportions in PM. Ethanol addition also increased the proportion of small particles, which confirmed the effects of ethanol on organic composition. Ethanol-gasoline reduced the concentrations of most PAH species, except those with small aromatic rings, e.g., naphthalene. Soot from ethanol-gasoline has lower activation energy of oxidation than that from gasoline. The results in this study indicate that ethanol-gasoline has positive effects on PM emissions control, as the soot oxidation activity is improved and the particle number concentrations are reduced at moderate and high engine loads. - Highlights: • Ethanol-gasoline reduces elemental carbon in PM. • Ethanol-gasoline increases volatile organic fraction in PM. • Soot generated from ethanol-gasoline has higher oxidation activity.

  3. Cavitation phenomena in a fuel injection nozzle of a diesel engine by neutron radiography

    International Nuclear Information System (INIS)

    Takenaka, N.; Kawabata, Y.; Miyata, D.; Kawabata, Y.; Sim, C. M.; Lim, I. C.

    2005-01-01

    Visualization of cavitation phenomena in a Diesel engine fuel injection nozzle was carried out by using neutron radiography system in Research Reactor Institute in Kyoto University and HANARO in Korea Atomic Energy Research Institute. A neutron chopper was synchronized to the engine rotation for high shutter speed exposures. A multi exposure method was applied to obtain a clear image as an ensemble average of the synchronized images. Some images were successfully obtained and suggested new understanding of the cavitation phenomena in a Diesel engine fuel injection nozzle

  4. Diesel Engine with Different Kind of Injection Systems Exhaust Gas Analysis

    OpenAIRE

    Mantas Smolnikovas; Gintas Viselga; Greta Viselgaitė; Algirdas Jasinskas

    2016-01-01

    The article presents an overview of structural evolution of diesel engines’ injection systems, air pollution caused by diesel engines and permissible emission rates. An analytical research on air pollution was also performed. Experimental studies evaluated air pollution during the emission of particulate matter according to diesel engine exploitation time and different constructions emissions.

  5. The Miller cycle effects on improvement of fuel economy in a highly boosted, high compression ratio, direct-injection gasoline engine: EIVC vs. LIVC

    International Nuclear Information System (INIS)

    Li, Tie; Gao, Yi; Wang, Jiasheng; Chen, Ziqian

    2014-01-01

    Highlights: • At high load, LIVC is superior over EIVC in improving fuel economy. • The improvement with LIVC is due to advanced combustion phasing and increased pumping work. • At low load, EIVC is better than LIVC in improving fuel economy. • Pumping loss with EIVC is smaller than with LIVC at low load. • But heat release rate with EIVC is slower than with LIVC. - Abstract: A combination of downsizing, highly boosting and direct injection (DI) is an effective way to improve fuel economy of gasoline engines without the penalties of reduced torque or power output. At high loads, however, knock problem becomes severer when increasing the intake boosting. As a compromise, geometric compression ratio (CR) is usually reduced to mitigate knock, and the improvement of fuel economy is discounted. Application of Miller cycle, which can be realized by either early or late intake valve closing (EIVC or LIVC), has the potential to reduce the effective CR and suppress knock. In this paper, the effects of EIVC and LIVC on the fuel economy of a boosted DI gasoline production engine reformed with a geometric CR of 12.0 are experimentally compared at low and high loads. Compared to the original production engine with CR 9.3, at the high load operation, the brake specific fuel consumption (BSFC) is improved by 4.7% with CR12.0 and LIVC, while the effect of EIVC on improving BSFC is negligibly small. At the low load operation, combined with CR12.0, LIVC and EIVC improve the fuel economy by 6.8% and 7.4%, respectively, compared to the production engine. The mechanism behind the effects of LIVC and EIVC on improving the fuel economy is discussed. These results will be a valuable reference for engine designers and researchers

  6. Direct Fuel Injection of LPG in Small Two-Stroke Engines

    OpenAIRE

    Yew Heng Teoh; Horizon Gitano-Briggs

    2011-01-01

    The commonly used carburetted two-stroke engines in developing countries have high exhaust emission and poor fuel efficiency. To meet more rigid emissions requirements, two-stroke vehicles are typically phase out in favour of four-stroke engines. The problems of ubiquitous legacy two-stroke vehicles remain unsolved by these measures and they are likely to be a major source of transport for many years to come. A number of technologies are available for solving the problems associated with two-...

  7. Opportunities and challenges in green house gases reduction using high pressure direct injection of natural gas

    International Nuclear Information System (INIS)

    Ouellette, P.

    2001-01-01

    In an effort to reduce Greenhouse Gases, Westport Innovations is developing a high pressure direct injection (HPDI) technology for gaseous fuels. This technology adapts the diesel cycle for gaseous fuels, since the diesel cycle provides high efficiency, high low-speed torque, fast transient capabilities and reliability. Because of their high efficiency, diesels are very favorable from a Greenhouse Gas (GHG) point of view, however they remain challenged by high nitrogen oxides (NOx) and particulate matter (PM) emissions. When directly injecting natural gas, NOx and PM emissions can be reduced by approximately 50% while maintaining the performance of the diesel engine. This allows the use of abundant and historically cheaper natural gas. Because of its lower carbon content per unit energy, natural gas also offers further GHG reduction over the diesel if the efficiency is preserved and if methane emissions are low. This paper discusses development efforts at Westport for several applications including on-highway trucks, light-duty delivery trucks and power generation

  8. Injection characteristics study of high-pressure direct injector for Compressed Natural Gas (CNG) using experimental and analytical method

    Science.gov (United States)

    Taha, Z.; Rahim, MF Abdul; Mamat, R.

    2017-10-01

    The injection characteristics of direct injector affect the mixture formation and combustion processes. In addition, the injector is converted from gasoline operation for CNG application. Thus measurement of CNG direct injector mass flow rate was done by independently tested a single injector on a test bench. The first case investigated the effect of CNG injection pressure and the second case evaluate the effect of pulse-width of injection duration. An analytical model was also developed to predict the mass flow rate of the injector. The injector was operated in a choked condition in both the experiments and simulation studies. In case 1, it was shown that mass flow rate through the injector is affected by injection pressure linearly. Based on the tested injection pressure of 20 bar to 60 bar, the resultant mass flow rate are in the range of 0.4 g/s to 1.2 g/s which are met with theoretical flow rate required by the engine. However, in Case 2, it was demonstrated that the average mass flow rate at short injection durations is lower than recorded in Case 1. At injection pressure of 50 bar, the average mass flow rate for Case 2 and Case 1 are 0.7 g/s and 1.1 g/s respectively. Also, the measured mass flow rate at short injection duration showing a fluctuating data in the range of 0.2 g/s - 1.3 g/s without any noticeable trends. The injector model able to predict the trend of the mass flow rate at different injection pressure but unable to track the fluctuating trend at short injection duration.

  9. Comparative performance and emissions study of a direct injection Diesel engine using blends of Diesel fuel with vegetable oils or bio-diesels of various origins

    International Nuclear Information System (INIS)

    Rakopoulos, C.D.; Antonopoulos, K.A.; Rakopoulos, D.C.; Hountalas, D.T.; Giakoumis, E.G.

    2006-01-01

    An extended experimental study is conducted to evaluate and compare the use of various Diesel fuel supplements at blend ratios of 10/90 and 20/80, in a standard, fully instrumented, four stroke, direct injection (DI), Ricardo/Cussons 'Hydra' Diesel engine located at the authors' laboratory. More specifically, a high variety of vegetable oils or bio-diesels of various origins are tested as supplements, i.e. cottonseed oil, soybean oil, sunflower oil and their corresponding methyl esters, as well as rapeseed oil methyl ester, palm oil methyl ester, corn oil and olive kernel oil. The series of tests are conducted using each of the above fuel blends, with the engine working at a speed of 2000 rpm and at a medium and high load. In each test, volumetric fuel consumption, exhaust smokiness and exhaust regulated gas emissions such as nitrogen oxides (NO x ), carbon monoxide (CO) and total unburned hydrocarbons (HC) are measured. From the first measurement, specific fuel consumption and brake thermal efficiency are computed. The differences in the measured performance and exhaust emission parameters from the baseline operation of the engine, i.e. when working with neat Diesel fuel, are determined and compared. This comparison is extended between the use of the vegetable oil blends and the bio-diesel blends. Theoretical aspects of Diesel engine combustion, combined with the widely differing physical and chemical properties of these Diesel fuel supplements against the normal Diesel fuel, are used to aid the correct interpretation of the observed engine behavior

  10. Impact of the injection dose of exhaust gases, on work parameters of combustion engine

    Science.gov (United States)

    Marek, W.; Śliwiński, K.

    2016-09-01

    This article is another one from the series in which were presented research results indicated the possible areas of application of the pneumatic injection using hot combustion gases proposed by Professor Jarnuszkiewicz. This publication present the results of the control system of exhaust gas recirculation. The main aim of this research was to determine the effect of exhaust gas recirculation to the operating parameters of the internal combustion engine on the basis of laboratory measurements. All measurements were performed at a constant engine speed. These conditions correspond to the operation of the motor operating an electrical generator. The study was conducted on the four-stroke two-cylinder engine with spark ignition. The study were specifically tested on the air injection system and therefore the selection of the rotational speed was not bound, as in conventional versions of operating parameters of the electrical machine. During the measurement there were applied criterion which used power control corresponding to the requirements of load power, at minimal values of engine speed. Recirculation value determined by the following recurrent position control valve of the injection doses inflator gas for pneumatic injection system. They were studied and recorded, the impact of dose of gases recirculation to the operating and ecological engine parameters such as power, torque, specific fuel consumption, efficiency, air fuel ratio, exhaust gas temperature and nitrogen oxides and hydrocarbons.

  11. Diesel Engine with Different Kind of Injection Systems Exhaust Gas Analysis

    Directory of Open Access Journals (Sweden)

    Mantas Smolnikovas

    2016-02-01

    Full Text Available The article presents an overview of structural evolution of diesel engines’ injection systems, air pollution caused by diesel engines and permissible emission rates. An analytical research on air pollution was also performed. Experimental studies evaluated air pollution during the emission of particulate matter according to diesel engine exploitation time and different constructions emissions.

  12. 78 FR 35747 - Airworthiness Directives; Engine Alliance Turbofan Engines

    Science.gov (United States)

    2013-06-14

    ... Airworthiness Directives; Engine Alliance Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT... Alliance GP7270 and GP7277 turbofan engines. This AD was prompted by damage to the high-pressure compressor... Alliance GP7270 and GP7277 turbofan engines with a high-pressure compressor (HPC) stage 6 disk, part number...

  13. Thrust Vectoring of a Continuous Rotating Detonation Engine by Changing the Local Injection Pressure

    International Nuclear Information System (INIS)

    Liu Shi-Jie; Lin Zhi-Yong; Sun Ming-Bo; Liu Wei-Dong

    2011-01-01

    The thrust vectoring ability of a continuous rotating detonation engine is numerically investigated, which is realized via increasing local injection stagnation pressure of half of the simulation domain compared to the other half. Under the homogeneous injection condition, both the flow-field structure and the detonation wave propagation process are analyzed. Due to the same injection condition along the inlet boundary, the outlines of fresh gas zones at different moments are similar to each other. The main flow-field features under thrust vectoring cases are similar to that under the baseline condition. However, due to the heterogeneous injection system, both the height of the fresh gas zone and the pressure value of the fresh gas in the high injection pressure zone are larger than that in the low injection pressure zone. Thus the average pressure in half of the engine is larger than that in the other half and the thrust vectoring adjustment is realized. (fundamental areas of phenomenology(including applications))

  14. Improvement of fuel injection system of locomotive diesel engine.

    Science.gov (United States)

    Li, Minghai; Cui, Hongjiang; Wang, Juan; Guan, Ying

    2009-01-01

    The traditional locomotive diesels are usually designed for the performance of rated condition and much fuel will be consumed. A new plunger piston matching parts of fuel injection pump and injector nozzle matching parts were designed. The experimental results of fuel injection pump test and diesel engine show that the fuel consumption rate can be decreased a lot in the most of the working conditions. The forced lubrication is adopted for the new injector nozzle matching parts, which can reduce failure rate and increase service life. The design has been patented by Chinese State Patent Office.

  15. Comparative study of oxihydrogen injection in turbocharged compression ignition engines

    Science.gov (United States)

    Barna, L.; Lelea, D.

    2018-01-01

    This document proposes for analysis, comparative study of the turbocharged, compression-ignition engine, equipped with EGR valve, operation in case the injection in intake manifold thereof a maximum flow rate of 1l/min oxyhydrogen resulted of water electrolysis, at two different injection pressures, namely 100 Pa and 3000 Pa, from the point of view of flue gas opacity. We found a substantial reduction of flue gas opacity in both cases compared to conventional diesel operation, but in different proportions.

  16. A Comparison of Three Second-generation Swirl-Venturi Lean Direct Injection Combustor Concepts

    Science.gov (United States)

    Tacina, Kathleen M.; Podboy, Derek P.; He, Zhuohui Joe; Lee, Phil; Dam, Bidhan; Mongia, Hukam

    2016-01-01

    Three variations of a low emissions aircraft gas turbine engine combustion concept were developed and tested. The concept is a second generation swirl-venturi lean direct injection (SV-LDI) concept. LDI is a lean-burn combustion concept in which the fuel is injected directly into the flame zone. All three variations were based on the baseline 9- point SV-LDI configuration reported previously. The three second generation SV-LDI variations are called the 5-recess configuration, the flat dome configuration, and the 9- recess configuration. These three configurations were tested in a NASA Glenn Research Center medium pressure flametube. All three second generation variations had better low power operability than the baseline 9-point configuration. All three configurations had low NO(sub x) emissions, with the 5-recess configuration generally having slightly lower NO(x) than the flat dome or 9-recess configurations. Due to the limitations of the flametube that prevented testing at pressures above 20 atm, correlation equations were developed for the at dome and 9-recess configurations so that the landing-takeoff NO(sub x) emissions could be estimated. The flat dome and 9-recess landing-takeoff NO(x) emissions are estimated to be 81-88% below the CAEP/6 standards, exceeding the project goal of 75% reduction.

  17. Effect of hydrogen on ethanol-biodiesel blend on performance and emission characteristics of a direct injection diesel engine.

    Science.gov (United States)

    Parthasarathy, M; Isaac JoshuaRamesh Lalvani, J; Dhinesh, B; Annamalai, K

    2016-12-01

    Environment issue is a principle driving force which has led to a considerable effort to develop and introduce alternative fuels for transportation. India has large potential for production of biofuels like biodiesel from vegetable seeds. Use of biodiesel namely, tamanu methyl ester (TME) in unmodified diesel engines leads to low thermal Efficiency and high smoke emission. To encounter this problem hydrogen was inducted by a port fueled injection system. Hydrogen is considered to be low polluting fuel and is the most promising among alternative fuel. Its clean burning characteristic and better performance attract more interest compared to other fuels. It was more active in reducing smoke emission in biodiesel. A main drawback with hydrogen fuel is the increased NO x emission. To reduce NO x emission, TME-ethanol blends were used in various proportions. After a keen study, it was observed that ethanol can be blended with biodiesel up to 30% in unmodified diesel engine. The present work deals with the experimental study of performance and emission characteristic of the DI diesel engine using hydrogen and TME-ethanol blends. Hydrogen and TME-ethanol blend was used to improve the brake thermal efficiency and reduction in CO, NO x and smoke emissions. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Emission potentials of future diesel fuel injection systems; Emissionspotentiale zukuenftiger Diesel-Einspritzsysteme

    Energy Technology Data Exchange (ETDEWEB)

    Schommers, J.; Breitbach, H.; Stotz, M.; Schnabel, M. [DaimlerChrysler AG (Germany)

    2007-07-01

    The historical evolution of the diesel engine correlates strongly with fuel injection system developments. Mercedes-Benz contributed significantly to the recent success of the diesel engine, being one of the first car manufacturers to introduce a modern common rail diesel engine in the Mercedes C220 CDI in 1997. The excellent characteristics of modern diesel engines resulted in a 50% market share in newly registered cars in Germany. These characteristics have to be further improved in the next years to keep the diesel engine attractive. Emissions and at the same time fuel consumption and noise need to be further reduced, while engine power has to go up. For Mercedes-Benz key steps to reach these goals are lower compression ratio, higher boost pressures, higher exhaust gas recirculation rates and better EGR cooling, multiple injection patterns and components with stable application parameters over lifetime. Important requirements for future fuel injection systems are high spray momentum, good stability over lifetime, good robustness of injected quantities for varying injection patterns and a low shot-to-shot variation of injected quantities. The high spray momentum has to be achieved especially for small injections and for part load operating points with low pressures. Therefore, the needle opening and closing velocities are of special importance. With special focus on the above requirements, different injector concepts were hydraulically evaluated. Both concepts in serial production and under development from system suppliers, as well as Mercedes-Benz developed prototype injector concepts were chosen. The concepts analysed are a servo-hydraulically driven injector with control piston, two servo-hydraulically driven injectors without control piston with differently adjusted hydraulics, and a direct driven injector, where the needle is driven directly from an actuator without servo-hydraulic amplification. The hydraulic investigations show an excellent performance of

  19. Analysis of gas turbine engines using water and oxygen injection to achieve high Mach numbers and high thrust

    Science.gov (United States)

    Henneberry, Hugh M.; Snyder, Christopher A.

    1993-01-01

    An analysis of gas turbine engines using water and oxygen injection to enhance performance by increasing Mach number capability and by increasing thrust is described. The liquids are injected, either separately or together, into the subsonic diffuser ahead of the engine compressor. A turbojet engine and a mixed-flow turbofan engine (MFTF) are examined, and in pursuit of maximum thrust, both engines are fitted with afterburners. The results indicate that water injection alone can extend the performance envelope of both engine types by one and one-half Mach numbers at which point water-air ratios reach 17 or 18 percent and liquid specific impulse is reduced to some 390 to 470 seconds, a level about equal to the impulse of a high energy rocket engine. The envelope can be further extended, but only with increasing sacrifices in liquid specific impulse. Oxygen-airflow ratios as high as 15 percent were investigated for increasing thrust. Using 15 percent oxygen in combination with water injection at high supersonic Mach numbers resulted in thrust augmentation as high as 76 percent without any significant decrease in liquid specific impulse. The stoichiometric afterburner exit temperature increased with increasing oxygen flow, reaching 4822 deg R in the turbojet engine at a Mach number of 3.5. At the transonic Mach number of 0.95 where no water injection is needed, an oxygen-air ratio of 15 percent increased thrust by some 55 percent in both engines, along with a decrease in liquid specific impulse of 62 percent. Afterburner temperature was approximately 4700 deg R at this high thrust condition. Water and/or oxygen injection are simple and straightforward strategies to improve engine performance and they will add little to engine weight. However, if large Mach number and thrust increases are required, liquid flows become significant, so that operation at these conditions will necessarily be of short duration.

  20. High-Compression-Ratio; Atkinson-Cycle Engine Using Low-Pressure Direct Injection and Pneumatic-Electronic Valve Actuation Enabled by Ionization Current and Foward-Backward Mass Air Flow Sensor Feedback

    Energy Technology Data Exchange (ETDEWEB)

    Harold Schock; Farhad Jaberi; Ahmed Naguib; Guoming Zhu; David Hung

    2007-12-31

    This report describes the work completed over a two and one half year effort sponsored by the US Department of Energy. The goal was to demonstrate the technology needed to produce a highly efficient engine enabled by several technologies which were to be developed in the course of the work. The technologies included: (1) A low-pressure direct injection system; (2) A mass air flow sensor which would measure the net airflow into the engine on a per cycle basis; (3) A feedback control system enabled by measuring ionization current signals from the spark plug gap; and (4) An infinitely variable cam actuation system based on a pneumatic-hydraulic valve actuation These developments were supplemented by the use of advanced large eddy simulations as well as evaluations of fuel air mixing using the KIVA and WAVE models. The simulations were accompanied by experimental verification when possible. In this effort a solid base has been established for continued development of the advanced engine concepts originally proposed. Due to problems with the valve actuation system a complete demonstration of the engine concept originally proposed was not possible. Some of the highlights that were accomplished during this effort are: (1) A forward-backward mass air flow sensor has been developed and a patent application for the device has been submitted. We are optimistic that this technology will have a particular application in variable valve timing direct injection systems for IC engines. (2) The biggest effort on this project has involved the development of the pneumatic-hydraulic valve actuation system. This system was originally purchased from Cargine, a Swedish supplier and is in the development stage. To date we have not been able to use the actuators to control the exhaust valves, although the actuators have been successfully employed to control the intake valves. The reason for this is the additional complication associated with variable back pressure on the exhaust valves when

  1. Cfd Aided Development of a Si-Di Engine Aide au développement d'un moteur à injection directe d'essence par modélisation 3D

    Directory of Open Access Journals (Sweden)

    Henriot S.

    2006-12-01

    Full Text Available Gasoline Direct Injection (GDI appears to be the most relevant way to improve fuel efficiency of SI engines. But today, GDI is essentially regarded as a suitable technology for relatively high displacement engines, and the literature shows that the R&D effort on GDI engines is generally made for bores larger than 80 mm. For small bore engines (bore below 75 mm, locating an injector in already congested cylinder heads, with ultra lean stratified combustion capability while maintaining high engine specific power and proper cylinder head cooling is a real challenge. For such an engine, IFP is developing a 3-valve per cylinder engine (NSDI-3, based on a narrow spacingconcept, with a spark-plug-close-to-the-injector design and a suitable piston to confine the gasoline spray within the vicinity of the ignition location. This paper describes the contribution of 3D modeling to the development of this engine, from the initial work during the design of the prototype combustion chamber, to the development and tuning of the prototype engine on the test bench. Depuis quelques années, l'injection directe d'essence apparaÎt comme l'une des voies d'investigation les plus performantes pour améliorer le rendement des moteurs à allumage commandé. Cependant, cette technologie est, actuellement, plutôt réservée aux moteurs de cylindrée assez importante, et les travaux de R&D présentés dans la littérature font surtout état de développement pour des moteurs d'alésage supérieur à 80 mm. En ce qui concerne les petits moteurs (alésage inférieur à 75 mm, implanter un injecteur dans une culasse déjà largement encombrée, avec un fort potentiel de combustion en mélange très pauvre stratifié, tout en maintenant de bonnes performances moteur et un circuit de refroidissement bien dimensionné, constitue un véritable défi. Pour un tel moteur, l'Institut français du pétrole (IFP développe une solution à 3 soupapes par cylindre (NSDI-3, basée sur

  2. MODELING OF ELECTRONIC GASOLINE INJECTION PROCESSES IN TWO STROKE ENGINE

    Directory of Open Access Journals (Sweden)

    Hraivoronskyi, Y.

    2013-06-01

    Full Text Available Basic provision of the processes developed mode, occurring in ignition fuel system with electronically controlled two stroke engine with positive ignition are given. Fuel injection process’ calculation results for the case of placing fuel injector into intake system presented.

  3. Pengaruh Prosentase Etanol terhadap Torsi dan Emisi Motor Indirect Injection dengan Memodifikasi Engine Control Module

    Directory of Open Access Journals (Sweden)

    Hadi Rahmad

    2016-10-01

    Full Text Available This research present the torque and exhaust emission level from four stroke indirect injection fuel system engine. An engine fueled by ethanol gasoline blend. The original Engine Controle Module injected lean mixture into Combustion Chamber. Lean Mixture decreased Torque drastically. Therefore, the Engine Controle Module was modified to produce stoichiometric mixture. Injector was controlled by digital pulse of Fuel Controller. Ethanol was added into gasoline 0% - 100% at 1500 rpm-5000 rpm. The result demonstrate that increasing ethanol concentration into gasoline fuel system, decreasing Torque, and CO, HC, CO2 emission. By increasing ethanol concentration also increase CO2 emission to 34.6%.

  4. Emission Characteristics for a Homogeneous Charged Compression Ignition Diesel Engine with Exhaust Gas Recirculation Using Split Injection Methodology

    Directory of Open Access Journals (Sweden)

    Changhee Lee

    2017-12-01

    Full Text Available Due to the serious issues caused by air pollution and global warming, emission regulations are becoming stricter. New technologies that reduce NOx and PM emissions are needed. To cope with these social exhaust gas regulation demands, many advanced countries are striving to develop eco-friendly vehicles in order to respond to stricter emissions regulations. The homogeneous charged compression ignition engine (HCCI incorporates a multi-stage combustion engine with multiple combustion modes, catalyst, direct fuel injection and partial mixing combustion. In this study, the HCCI combustion was applied to analyze and review the results of engines applying HCCI combustion without altering the conventional engine specifications. The optimization of exhaust gas recirculation (EGR and compression ratio changes provides an optimal fuel economy. In this study, potential for optimum economy within the range of IMEP 0.8 MPa has been evaluated.

  5. Experimental investigations of the effect of pilot injection on performance, emissions and combustion characteristics of Karanja biodiesel fuelled CRDI engine

    International Nuclear Information System (INIS)

    Dhar, Atul; Agarwal, Avinash Kumar

    2015-01-01

    Highlights: • Effect of multiple injections on CRDI engine performance, emission and combustion. • Effect of multiple injections, injection pressures and injection timings on biodiesel. • Lower biodiesel blends showed lower BSCO, BSHC but higher BSNOx emissions. • Maximum cylinder pressure at higher FIP was higher at same SOPI and SOMI. • Combustion duration of KOME50 was higher than mineral diesel. - Abstract: Pilot and post injections are being used in modern diesel engines for improving engine performance in addition to meeting stringent emission norms. Biodiesel produced from different feedstocks is gaining global recognition as partial replacement for mineral diesel in compression ignition (CI) engines. In this study, 10%, 20% and 50% Karanja biodiesel blends were used for investigation of pilot injections, injection pressures and injection timings on biodiesel blends. Experiments were carried out in a single cylinder CRDI research engine in multiple injection mode at 500 and 1000 bar fuel injection pressure (FIP) under varying start of pilot injection (SOPI) and start of main injection (SOMI) timings. Brake specific fuel consumption (BSFC) increased with increasing Karanja biodiesel concentration in test fuels however brake thermal efficiency (BTE) of biodiesel blends was slightly higher than mineral diesel. Lower biodiesel blends showed lower brake specific carbon monoxide (BSCO) and brake specific hydrocarbon (BSHC) emissions than mineral diesel. Brake specific nitrogen oxides (BSNOx) emissions from KOME20 and KOME10 were higher than mineral diesel. Combustion duration of KOME50 was also higher than mineral diesel

  6. Mechanism of hydrocarbon reduction using multiple injection in a natural gas fuelled/micro-pilot diesel ignition engine

    Energy Technology Data Exchange (ETDEWEB)

    Micklow, G.J.; Gong, W. [University of North Carolina, Charlotte, NC (United States)

    2002-03-01

    Research has shown that a large amount of natural gas (NG) is unburned at light loads in an NG fuelled/micro-pilot diesel compression ignition engine. A mechanism of unburned hydrocarbon (HC) reduction using multiple injections of micro-pilot diesel has been proposed in this paper. Multidimensional computations were carried out for a dual-fuel engine based on a modified CAT3401 engine configuration. The computations show that a split injection with a small percentage (e.g. 30 per cent of diesel in the second injection pulse) can significantly reduce HC, CO and NO{sub x} emissions. Based on parax metric studies to optimize the timing of both of the injection pulses, HC emissions could be reduced by 90 per cent, with a reduction in CO emissions of 50 per cent and NO{sub x} emissions of 70 per cent in comparison to a singlex injection pulse-base case configuration. (author)

  7. Numerical study of the influence of Diesel post injection and exhaust gas expansion on the thermal cycle of an automobile engine

    OpenAIRE

    2010-01-01

    Abstract This study deals with the development of a numerical tool developed to analyze the thermo-management of the heat rejection from the fuel combustion in the case of a four cylinder 2 L ? 110 HP direct injection Diesel engine. It is composed of two main elements: the first one simulates all the phenomena linked to the combustion, the second one is about thermal exchanges in the heart of the engine. We only deal with the first one here. The combustion study is based...

  8. Contingency power for small turboshaft engines using water injection into turbine cooling air

    Science.gov (United States)

    Biesiadny, Thomas J.; Berger, Brett; Klann, Gary A.; Clark, David A.

    1987-01-01

    Because of one engine inoperative requirements, together with hot-gas reingestion and hot day, high altitude takeoff situations, power augmentation for multiengine rotorcraft has always been of critical interest. However, power augmentation using overtemperature at the turbine inlet will shorten turbine life unless a method of limiting thermal and mechanical stresses is found. A possible solution involves allowing the turbine inlet temperature to rise to augment power while injecting water into the turbine cooling air to limit hot-section metal temperatures. An experimental water injection device was installed in an engine and successfully tested. Although concern for unprotected subcomponents in the engine hot section prevented demonstration of the technique's maximum potential, it was still possible to demonstrate increases in power while maintaining nearly constant turbine rotor blade temperature.

  9. Co-combustion of biodiesel with oxygenated fuels in direct injection diesel engine

    Directory of Open Access Journals (Sweden)

    Tutak Wojciech

    2017-01-01

    Full Text Available The paper presents results of experimental investigation of cocombustion process of biodiesel (B100 blended with oxygenated fuels with 20% in volume. As the alternative fuels ware used hydrated ethanol, methanol, 1-butanol and 2-propanol. It was investigated the influence of used blends on operating parameters of the test engine and exhaust emission (NOx, CO, THC, CO2. It is observed that used blends are characterized by different impact on engine output power and its efficiency. Using biodiesel/alcohol blend it is possible to improve engine efficiency with small drop in indicated mean effective pressure (IMEP. Due to combustion characteristic of biodiesel/alcohol obtained a slightly larger specific NOx emission. It was also observed some differences in combustion phases due to various values of latent heat of evaporation of used alcohols and various oxygen contents. Test results confirmed that the combustion process occurring in the diesel engine powered by blend takes place in a shorter time than in the typical diesel engine.

  10. Laser induced plasma methodology for ignition control in direct injection sprays

    International Nuclear Information System (INIS)

    Pastor, José V.; García-Oliver, José M.; García, Antonio; Pinotti, Mattia

    2016-01-01

    Highlights: • Laser Induced Plasma Ignition system is designed and applied to a Diesel Spray. • A method for quantification of the system effectiveness and reliability is proposed. • The ignition system is optimized in atmospheric and engine-like conditions. • Higher system effectiveness is reached with higher ambient density. • The system is able to stabilize Diesel combustion compared to auto-ignition cases. - Abstract: New combustion modes for internal combustion engines represent one of the main fields of investigation for emissions control in transportation Industry. However, the implementation of lean fuel mixture condition and low temperature combustion in real engines is limited by different unsolved practical issues. To achieve an appropriate combustion phasing and cycle-to-cycle control of the process, the laser plasma ignition system arises as a valid alternative to the traditional electrical spark ignition system. This paper proposes a methodology to set-up and optimize a laser induced plasma ignition system that allows ensuring reliability through the quantification of the system effectiveness in the plasma generation and positional stability, in order to reach optimal ignition performance. For this purpose, experimental tests have been carried out in an optical test rig. At first the system has been optimized in an atmospheric environment, based on the statistical analysis of the plasma records taken with a high speed camera to evaluate the induction effectiveness and consequently regulate and control the system settings. The same optimization method has then been applied under engine-like conditions, analyzing the effect of thermodynamic ambient conditions on the plasma induction success and repeatability, which have shown to depend mainly on ambient density. Once optimized for selected engine conditions, the laser plasma induction system has been used to ignite a direct injection Diesel spray, and to compare the evolution of combustion

  11. Design and experimental investigations on six-stroke SI engine using acetylene with water injection.

    Science.gov (United States)

    Gupta, Keshav; Suthar, Kishanlal; Jain, Sheetal Kumar; Agarwal, Ghanshyam Das; Nayyar, Ashish

    2018-06-02

    In the present study, a four-stroke cycle gasoline engine is redesigned and converted into a six-stroke cycle engine and experimental study has been conducted using gasoline and acetylene as fuel with water injection at the end of the recompression stroke. Acetylene has been used as an alternative fuel along with gasoline and performance of the six-stroke spark ignition (SI) engine with these two fuels has been studied separately and compared. Brake power and thermal efficiency are found to be 5.18 and 1.55% higher with acetylene as compared to gasoline in the six-stroke engine. However, thermal efficiency is found to be 45% higher with acetylene in the six-stroke engine as compared to four-stroke SI engine. The CO and HC emissions were found to be reduced by 13.33 and 0.67% respectively with acetylene as compared to gasoline due to better combustion of acetylene. The NO x emission was reduced by 5.65% with acetylene due to lower peak temperature by water injection. The experimental results showed better engine performance and emissions with acetylene as fuel in the six-stroke engine.

  12. Formation and emission of organic pollutants from diesel engines

    International Nuclear Information System (INIS)

    Bertoli, C.; Ciajolo, A.; D'Anna, A.; Barbella, R.

    1993-01-01

    The emission of soot and polycyclic aromatic hydrocarbons (PAH) from diesel engines results from the competition between oxidative and pyrolytic routes which the fuel takes in the unsteady, heterogeneous conditions of the diesel combustion process. In-cylinder sampling and analysis of particulate (soot and condensed hydrocarbon species), light hydrocarbons and gaseous inorganic species were carried out in two locations of a single cylinder direct injection diesel engine by means of a fast sampling valve in order to follow the behaviour of a diesel fuel during the engine cycle. The effect of fuel quality (volatility, aromatic content, cetane number) and air/fuel mass feed ratio on soot, PAH, and light and heavy hydrocarbons was also investigated by direct sampling and chemical analysis of the exhausts emitted from a direct injection diesel engine (D.I.) and an indirect injection diesel engine (I.D.I.)

  13. Effect of piston profile on performance and emission characteristics of a GDI engine with split injection strategy - A CFD study

    Science.gov (United States)

    Karaya, Y.; Mallikarjuna, J. M.

    2017-09-01

    Gasoline direct injection (GDI) engines have gained popularity in the recent times because of lower fuel consumption and exhaust emissions. But in these engines, the mixture preparation plays an important role which affects combustion, performance and emission characteristics. The mixture preparation in turn depends mainly upon combustion chamber geometry. Therefore, in this study, an attempt has been made to understand the effect of piston profile on the performance and emission characteristics in a GDI engine. The analysis is carried out on a four-stroke wall guided GDI engine using computational fluid dynamics (CFD). The spray breakup model used is validated with the available experimental results from the literature to the extent possible. The analysis is carried out for four piston profiles viz., offset pentroof with offset bowl (OPOB), flat piston with offset bowl (FPOB), offset pentroof with offset scoop (OPOS) and inclined piston with offset bowl (IPOB) fitted in an engine equipped with a six-hole injector with the split injection ratio of 30:70. All the CFD simulations are carried out at the engine speed of 2000 rev/min., with the overall equivalence ratio of about 0.65±0.05. The performance and emission characteristics of the engine are compared while using the above piston profiles. It is found that, the OPOB piston is preferred compared to that of the other pistons because it has better in-cylinder flow, IMEP and lower HC emissions compared to that of other pistons.

  14. Development and application of multi-zone model for combustion and pollutants formation in direct injection diesel engine running with vegetable oil or its bio-diesel

    International Nuclear Information System (INIS)

    Rakopoulos, C.D.; Antonopoulos, K.A.; Rakopoulos, D.C.

    2007-01-01

    A multi-zone model for calculation of the closed cycle of a direct injection (DI) Diesel engine is presented and applied for the interesting case of its operation with vegetable oil (cottonseed) or its derived bio-diesel (methyl ester) as fuels, which recently are considered as promising alternatives (bio-fuels) to petroleum distillates. Although there are many experimental studies, there is an apparent scarcity of theoretical models scrutinizing the formation mechanisms of combustion generated emissions when using these fuels. The model is two dimensional, multi-zone with the issuing jets (from the nozzle) divided into several discrete volumes, called 'zones', formed along the direction of the fuel injection and across it. The model follows each zone, with its own time history, as the spray penetrates into the swirling air environment (forming the non-burning zone) of the combustion chamber, before and after wall impingement. Droplet evaporation and jet mixing models are used to determine the amount of fuel and entrained air in each zone available for combustion. The mass, energy and state equations are applied in each zone to yield local temperatures and cylinder pressure histories. The concentrations of the various constituents are calculated by adopting a chemical equilibrium scheme for the C-H-O-N system of 11 species considered, together with the chemical rate equations for the calculation of nitric oxide (NO). A model for evaluation of soot formation and oxidation rates is included. The results from the relevant computer program for the in cylinder pressure, exhaust nitric oxide concentration (NO) and soot density are compared favorably with the corresponding measurements from an experimental investigation conducted on a fully automated test bed, standard 'Hydra', DI Diesel engine installed at the authors' laboratory. Iso-contour plots of equivalence ratio, temperature, NO and soot inside the combustion chamber at various instants of time when using these

  15. Performance and combustion analysis of Mahua biodiesel on a single cylinder compression ignition engine using electronic fuel injection system

    Directory of Open Access Journals (Sweden)

    Gunasekaran Anandkumar

    2016-01-01

    Full Text Available In this investigation, experiment is carried out on a 1500 rpm constant speed single cylinder Diesel engine. The test is carried out with Neat diesel, neat biodiesel, and blend B20. The engine considered was run with electronic fuel injection system supported by common rail direct injection to obtain high atomization and effective air utilization inside the combustion chamber. The performance of the engine in terms of break thermal efficiency and brake specific energy consumption was found and compared. The B20 blend shows 1.11% decrease in break thermal efficiency and 3.35% increase in brake specific energy consumption than diesel. The combustion characteristics found are in-cylinder pressure, rate of pressure rise, and heat release rate and compared for peak pressure load to understand the nature of combustion process. For each fuel test run, the maximum peak pressure is observed at part load condition. The rate of change of pressure and heat release rate of diesel is high compared to pure biodiesel and B20 blend. The diffusion combustion is observed to be predominant in case of B100 than B20 and Neat diesel.

  16. 78 FR 22168 - Airworthiness Directives; International Aero Engines AG Turbofan Engines

    Science.gov (United States)

    2013-04-15

    ... Airworthiness Directives; International Aero Engines AG Turbofan Engines AGENCY: Federal Aviation Administration... International Aero Engines AG (IAE), V2525-D5 and V2528-D5 turbofan engines, with a certain No. 4 bearing... turbofan engines, serial numbers V20001 through V20285, with No. 4 bearing internal scavenge tube, part...

  17. Study of the Influence of Key Parameters on the Dynamic Spray Characteristics of Natural Gas Direct Injection Engine%关键参数对直喷式天然气发动机喷雾动态性的影响研究

    Institute of Scientific and Technical Information of China (English)

    韩志强; 钱云寿; 冷松蓬; 马帅; 夏琦

    2017-01-01

    Jet development and mixing process of natural gas direct injection engine are the key to achieve high efficiency and clean combustion.This research worked on the characteristic of directly injected natural gas spray in cylinder based on a combustion bomb with a schlieren test system.The influence on direct injection natural gas engine spray dynamic characteristics was systematically analyzed by the ambient temperature,ambient pressure,injection pressure and other parameters.The results showed that the ambient pressure in combustion chamber and the injection pressure highly influenced the jet spray development process.With the enlargement of ambient pressure,the spray penetration rate compared to slow,while the spray cone angle diffusion increased;the greater the injection pressure,the expedited the spray penetration,and the more amplified,the spray diffusion cone angle.In addition,the study shows that the influence of cylinder temperature on the develooment of the sorav is relativelv small.%直喷式天然气发动机缸内喷雾发展和动态混合历程是实现高效清洁燃烧的关键.基于定容燃烧弹可视化纹影试验系统,分析了缸内温度、缸内压力、喷射压力等参数对直喷式天然气发动机喷雾动态特性的影响规律.结果表明:缸内压力和喷射压力对天然气喷雾发展历程产生显著影响,随着缸内压力变大,喷雾贯穿速度相对变慢,喷雾扩散锥角变大;喷射压力越大,喷雾贯穿速度越快,喷雾扩散锥角越大.缸内温度对喷雾发展影响相对较小.

  18. E85 Optimized Engine

    Energy Technology Data Exchange (ETDEWEB)

    Bower, Stanley [Ford Motor Company, Dearborn, MI (United States)

    2011-12-31

    A 5.0L V8 twin-turbocharged direct injection engine was designed, built, and tested for the purpose of assessing the fuel economy and performance in the F-Series pickup of the Dual Fuel engine concept and of an E85 optimized FFV engine. Additionally, production 3.5L gasoline turbocharged direct injection (GTDI) EcoBoost engines were converted to Dual Fuel capability and used to evaluate the cold start emissions and fuel system robustness of the Dual Fuel engine concept. Project objectives were: to develop a roadmap to demonstrate a minimized fuel economy penalty for an F-Series FFV truck with a highly boosted, high compression ratio spark ignition engine optimized to run with ethanol fuel blends up to E85; to reduce FTP 75 energy consumption by 15% - 20% compared to an equally powered vehicle with a current production gasoline engine; and to meet ULEV emissions, with a stretch target of ULEV II / Tier II Bin 4. All project objectives were met or exceeded.

  19. Idling operation apparatus for multicylinder fuel injection engine

    Energy Technology Data Exchange (ETDEWEB)

    Kanahira, A

    1974-11-20

    A device to cut off the fuel supply to a number of cylinders at idling is described for those engines equipped with multicylinder fuel injection systems. The discontinuation of the fuel gas supply to the cylinders is made by a magnetically operated valve which is related to the accelerator. When the engine is idling, a switch activates the magnetic valve and the tube leading to the cylinder closes while a valve on the tube leading to a dual tank opens, and the pumped gas returns to the tank. This valve is installed on several cylinders, but not on all. Thus, at idling only a certain number of cylinders are firing, which lowers the hydrocarbon levels in the exhaust gas since non-firing cylinders intake and discharge only air.

  20. Rapid prototyping systems for the development of new fuel-injection concepts for diesel engines; Einspritz-Prototyping-System zur Entwicklung neuer Einspritzkonzepte bei Dieselmotoren

    Energy Technology Data Exchange (ETDEWEB)

    Kasper, M. [ETAS GmbH, Stuttgart (Germany)

    2004-10-01

    The article uses the example of solenoid-based fuel injectors for diesel engines to demonstrate how a combination of reconfigurable logic and microcontrollers may be employed towards the rapid implementation of new control concepts for timely testing either directly on the engine or in the vehicle. Emphasis is given to the development and optimization of electronic engine management components. In contrast to the nonexistent modification options on conventional production ECUs, the new concept allows for the modification and fine-tuning of a number of injection parameters. The rapid prototyping system is a joint development of the Research and Advanced Engineering Department of Robert Bosch GmbH and ETAS GmbH. (orig.)

  1. Measurement and Simulation of Pollutant Emissions from Marine Diesel Combustion Engine and Their Reduction by Ammonia Injection

    Directory of Open Access Journals (Sweden)

    Nader Larbi

    2009-01-01

    Full Text Available Taking into account the complexity and cost of a direct experimental approach, the recourse to a tool of simulation, which can also predict inaccessible information by measurement, offers an effective and fast alternative to apprehend the problem of pollutant emissions from internal combustion engines. An analytical model based on detailed chemical kinetics employed to calculate the pollutant emissions of a marine diesel engine gave satisfactory results, in general, compared to experimentally measured results. Especially the NO emission values are found to be higher than the limiting values tolerated by the International Maritime Organization (IMO. Thus, this study is undertaken in order to reduce these emissions to the maximum level. The reduction of pollutant emissions is apprehended with ammonia injection.

  2. Multi-Element Lean Direct Injection Combustor Module, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop a Multi-Element Lean Direct Injection, ME-LDI, Combustion concept with the following innovative features: 1. Independent, mini burning zones...

  3. On the effect of Di-Ethyl-Ether (DEE) injection upon the cold starting of a biodiesel fuelled compression ignition engine

    Science.gov (United States)

    Clenci, Adrian; Niculescu, Rodica; Iorga-Simǎn, Victor; Tricǎ, Alina; Danlos, Amélie

    2017-02-01

    The use of biodiesel fuel in compression ignition engines has the potential to reduce CO2, which can lead to a reduction in global warming and environmental hazards. Biodiesel is an attractive fuel, as it is made from renewable resources. A major drawback associated with the use of biodiesel, however, is its poor cold flow properties, which have a direct influence on the cold starting performance of the engine. This paper is a consequence of a study on assessing the cold-starting performance of a compression ignition engine fueled with different blends of fossil diesel fuel and biodiesel. Through experimental investigations, it was found that the engine starting at -20°C was no longer possible in the case of using B50 (50% diesel + 50% biofuel made from sunflower oil). In order to "force" the engine starting in this particular situation, Di-Ethyl-Ether (DEE) was injected into the intake manifold. DEE being a highly flammable substance, the result was a sudden and explosive engine starting, the peak pressure in the monitored cylinder in the first successful engine cycle being almost twice the one which is usually considered as normal. Thus, to explain the observed phenomena, we launched this work relying on the analysis of the in-cylinder instantaneous pressure evolution, which was acquired during cranking, stabilizing and idling phases. Moreover, since the cause of the sudden and explosive engine starting was the DEE, by using a CFD approach, we also obtained results regarding the inter-cylinder distribution of the injected DEE.

  4. Lambda quantification by laser optical measuring methods on a supercharged Otto engine with Benz indirect injection; Lambdaquantifizierung mittels laseroptischer Messmethoden am aufgeladenen Ottomotor mit Benzindirekteinspritzung

    Energy Technology Data Exchange (ETDEWEB)

    Rogler, Philipp

    2010-07-01

    For the optimization of upcoming SI engine generations it is indispensable to understand the mixture formation process in detail because it is the basis requirement for reducing emissions and fuel consumption. On this account, fuel sprays used for gasoline direct injection are investigated with advanced laser optical measurement techniques. The spatial fuel distribution of both vapor and liquid phase is measured with a new technology approach, in which the 3D-tomography is combined with the laser induced exciplex fluorescence to create a new technology. With this laser-induced exciplex fluorescence tomography (TLIEF) the vapor and liquid phase fuel distribution of annular orifice and multi hole injectors are investigated under stationary boundary conditions in an optically accessible spray vessel. The particle density inside the spray chamber is kept constant and set to resemble that of a typical stratified engine operation point during the injection phase. Pressure and temperature are varied for parameter studies. The 3D spray visualizations show a significant dependency of the spray propagation on the ambient temperature. The vaporized fuel generated by multihole injectors with nearby oriented spray plumes is elongated differently under high ambient temperatures (500 K) compared to room temperature. PIV flow field measurements revealed that the reason for this temperature dependent behavior is the spray induced air flow. The vapor phase, which is with increasing temperatures in greater distance from the injector predominantly present, with its, compared to fuel droplets, lower moment of inertia is stronger elongated by the spray induced air flow. For a more detailed understanding of the mixture formation processes, the air-fuel-ratio {lambda} is computed from the quantified TLIEF signals. Therefore the total fluorescence intensity within the spray volume at a time where the vaporization process has been completed is equalized to the known total injected mass

  5. 76 FR 77108 - Airworthiness Directives; International Aero Engines Turbofan Engines

    Science.gov (United States)

    2011-12-12

    ... Airworthiness Directives; International Aero Engines Turbofan Engines AGENCY: Federal Aviation Administration...-D5, V2530-A5, and V2533-A5 turbofan engines. This AD was prompted by three reports of high- pressure..., V2524-A5, V2525-D5, V2527-A5, V2527E-A5, V2527M-A5, V2528- D5, V2530-A5, and V2533-A5 turbofan engines...

  6. Redistribution of contaminants from pig slurry after direct injection into soil

    DEFF Research Database (Denmark)

    Amin, Mostofa; Bech, T B; Forslund, A

    2010-01-01

    The redistribution of pig manure-borne contaminants after direct injection to soil was investigated in a field study. The spatial distribution of Escherichia coli, Salmonella Typhimurium Bacteriophage 28B and other slurry components in and around the injection slit was measured on day 0.15, 1, 6...

  7. Emission constrained multiple-pulse fuel injection optimisation and control for fuel-efficient diesel engines

    NARCIS (Netherlands)

    Luo, X.; Jager, de A.G.; Willems, F.P.T.

    2015-01-01

    With the application of multiple-pulse fuel injec- tion profiles, the performance of diesel engines is enhanced in terms of low fuel consumption and low engine-out emission levels. However, the calibration effort increases due to a larger number of injection timing parameters. The difficulty of

  8. Comparative studies on the performance and emissions of a direct injection diesel engine fueled with neem oil and pumpkin seed oil biodiesel with and without fuel preheater.

    Science.gov (United States)

    Ramakrishnan, Muneeswaran; Rathinam, Thansekhar Maruthu; Viswanathan, Karthickeyan

    2018-02-01

    In the present experimental analysis, two non-edible oils namely neem oil and pumpkin seed oil were considered. They are converted into respective biodiesels namely neem oil methyl ester (B1) and pumpkin seed oil methyl ester (B2) through transesterification process and their physical and chemical properties were examined using ASTM standards. Diesel was used as a baseline fuel in Kirloskar TV1 model direct injection four stroke diesel engine. A fuel preheater was designed and fabricated to operate at various temperatures (60, 70, and 80 °C). Diesel showed higher brake thermal efficiency (BTE) than biodiesel samples. Lower brake specific fuel consumption (BSFC) was obtained with diesel than B1 sample. B1 exhibited lower BSFC than B2 sample without preheating process. High preheating temperature (80 °C) results in lower fuel consumption for B1 sample. The engine emission characteristics like carbon monoxide (CO), hydrocarbon (HC), and smoke were found lower with B1 sample than diesel and B2 except oxides of nitrogen (NOx) emission. In preheating of fuel, B1 sample with high preheating temperature showed lower CO, HC, and smoke emission (except NOx) than B2 sample.

  9. Image processing analysis of combustion for D. I. diesel engine with high pressure fuel injection. ; Effects of air swirl and injection pressure. Nensho shashin no gazo shori ni yoru koatsu funsha diesel kikan no nensho kaiseki. ; Swirl oyobi funsha atsuryoku no eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Yamaguchi, I. (Japan Automobile Research Institute, Inc., Tsukuba (Japan)); Tsujimura, K.

    1994-02-25

    This paper reports an image processing analysis of combustion for a high-pressure direct injection diesel engine on the effects of air swirl and injection pressure upon combustion in the diesel engine. The paper summarizes a method to derive gas flow and turbulence strengths, and turbulent flow mixing velocity. The method derives these parameters by detecting movement of brightness unevenness on two flame photographs through utilizing the mutual correlative coefficients of image concentrations. Five types of combustion systems having different injection pressures, injection devices, and swirl ratios were used for the experiment. The result may be summarized as follows: variation in the average value of the turbulent flow mixing velocities due to difference in the swirl ratio is small in the initial phase of diffusion combustion; the difference is smaller in the case of high swirl ratio than in the case of low swirl ratio after the latter stage of the injection; the average value is larger with the higher the injection pressure during the initial stage of the combustion; after termination of the injection, the value is larger in the low pressure injection; and these trends agree with the trend in the time-based change in heat generation rates measured simultaneously. 6 refs., 14 figs., 2 tabs.

  10. The Influence of Injection Timing on Performance Characteristics of Diesel Engine Using Jatropha Biodiesel with and without Partial Hydrogenation

    Directory of Open Access Journals (Sweden)

    Rizqon Fajar

    2014-07-01

    Full Text Available Experimental research has been conducted to investigate the effects of blend of hydrogenated and unhydrogenated Jatropha biodiesel with diesel fuel in volume ratio of 30:70 (B30 on combustion characteristics (BSFC, thermal efficiency and smoke emission of single cylinder diesel engine. In this experiment, engine speed was kept constant at 1,500, 2,500, and 3,500 rpm with maximum engine load at BMEP 5 bar and injection timings were varied. Experimental result showed that at engine speed 1,500 rpm, BSFC of B30 hydrogenated and unhydrogenated Jatropha biodiesel were higher than it of diesel fuel at all injection timings (10° to 18° BTDC. At the same condition, partial hydrogenated Jatropha biodiesel showed higher BSFC than unhydrogenated Jatropha biodiesel. However, the difference in BSFC became smaller for all fuels at engine speed 2,500 rpm and 3,500 rpm at all injection timing. Jatropha biodiesel with and without partial hydrogenation tend to have higher thermal efficiency compared with diesel fuel at all engine speed and injection timing. The best injection timings to operate B30 Jatropha biodiesel with and without hydrogenation were 14°, 18° and 24° BTDC at engine speed 1,500, 2,500, and 3,500 rpm respectively. This conclusion was deduced based on the minimum value of BSFC and the maximum value of thermal efficiency. Smoke emissions for all fuels were in the same level for all conditions.

  11. Geothermal direct use engineering and design guidebook

    International Nuclear Information System (INIS)

    Lienau, P.J.; Lunis, B.C.

    1991-01-01

    The Geothermal Direct Use Engineering and Design Guidebook is designed to be a comprehensive, thoroughly practical reference guide for engineers and designers of direct heat projects. These projects could include the conversion of geothermal energy into space heating and cooling of buildings, district heating, greenhouse heating, aquaculture and industrial processing. The Guidebook is directed at understanding the nature of geothermal resources and the exploration of the resources, fluid sampling techniques, drilling, and completion of geothermal wells through well testing, and reservoir evaluation. It presents information useful to engineers on the specification of equipment including well pumps, piping, heat exchangers, space heating equipment, heat pumps and absorption refrigeration. A compilation of current information about greenhouse aquaculture and industrial applications is included together with a discussion of engineering cost analysis, regulation requirements, and environmental consideration. The purpose of the Guidebook is to provide an integrated view for the development of direct use projects for which there is a very large potential in the United States

  12. Geothermal direct use engineering and design guidebook

    Energy Technology Data Exchange (ETDEWEB)

    Lienau, P.J.; Lunis, B.C. (eds.)

    1991-01-01

    The Geothermal Direct Use Engineering and Design Guidebook is designed to be a comprehensive, thoroughly practical reference guide for engineers and designers of direct heat projects. These projects could include the conversion of geothermal energy into space heating and cooling of buildings, district heating, greenhouse heating, aquaculture and industrial processing. The Guidebook is directed at understanding the nature of geothermal resources and the exploration of the resources, fluid sampling techniques, drilling, and completion of geothermal wells through well testing, and reservoir evaluation. It presents information useful to engineers on the specification of equipment including well pumps, piping, heat exchangers, space heating equipment, heat pumps and absorption refrigeration. A compilation of current information about greenhouse aquaculture and industrial applications is included together with a discussion of engineering cost analysis, regulation requirements, and environmental consideration. The purpose of the Guidebook is to provide an integrated view for the development of direct use projects for which there is a very large potential in the United States.

  13. Geothermal direct use engineering and design guidebook

    Energy Technology Data Exchange (ETDEWEB)

    Bloomquist, R.G.; Culver, G.; Ellis, P.F.; Higbee, C.; Kindle, C.; Lienau, P.J.; Lunis, B.C.; Rafferty, K.; Stiger, S.; Wright, P.M.

    1989-03-01

    The Geothermal Direct Use Engineering and Design Guidebook is designed to be a comprehensive, thoroughly practical reference guide for engineers and designers of direct heat projects. These projects could include the conversion of geothermal energy into space heating cooling of buildings, district heating, greenhouse heating, aquaculture and industrial processing. The Guidebook is directed at understanding the nature of geothermal resources and the exploration of these resources, fluid sampling techniques, drilling, and completion of geothermal wells through well testing, and reservoir evaluation. It presents information useful to engineers on the specification of equipment including well pumps, piping, heat exchangers, space heating equipment, heat pumps and absorption refrigeration. A compilation of current information about greenhouse, aquaculture and industrial applications is included together with a discussion of engineering cost analysis, regulation requirements, and environmental considerations. The purpose of the Guidebook is to provide an integrated view for the development of direct use projects for which there is a very potential in the United States.

  14. Effects of pilot injection parameters on low temperature combustion diesel engines equipped with solenoid injectors featuring conventional and rate-shaped main injection

    International Nuclear Information System (INIS)

    D’Ambrosio, S.; Ferrari, A.

    2016-01-01

    Highlights: • The influence of the principal pilot injection parameters is discussed for low-temperature combustion systems. • Swirl-sweep and dwell-time sweep results are combined to analyze soot emissions. • The pilot injection effects are investigated in injection profiles featuring rate-shaped main injections. - Abstract: The potential of pilot injection has been assessed on a low-temperature combustion diesel engine for automotive applications, which was characterized by a reduced compression-ratio, high EGR rates and postponed main injection timings. Dwell time sweeps have been carried out for pilot injections with distinct energizing times under different representative steady-state working conditions of the medium load and speed area of the New European Driving Cycle. The results of in-cylinder analyses of the pressure, heat-release rate, temperature and emissions are presented. Combustion noise has been shown to decrease significantly when the pilot injected mass increases, while it is scarcely affected by the dwell time between the pilot and main injections. The HC, CO and fuel consumption trends, with respect to both the pilot injection dwell time and mass, are in line with those of conventional combustion systems, and in particular decreasing trends occur as the pilot injection energizing time is increased. Furthermore, a reduced sensitivity of NO_x emissions to both dwell time and pilot injected mass has been found, compared to conventional combustion systems. Finally, it has been observed that soot emissions diminish as the energizing time is shortened, and their dependence on dwell time is influenced to a great extent by the presence of local zones with reduced air-to-fuel ratios within the cylinder. A combined analysis of the results of swirl sweeps and dwell time sweeps is here proposed as a methodology for the detection of any possible interference between pilot combustion burned gases and the main injected fuel. The effect of pilot

  15. The effects of de-humidification and O{sub 2} direct injection in oxy-PC combustion

    Energy Technology Data Exchange (ETDEWEB)

    Choi, C.G.; Na, I.H.; Lee, J.W.; Chae, T.Y.; Yang, W. [Korea Insitute of Industrial Technology, Seoul (Korea, Republic of). Energy System R and D Dept.

    2013-07-01

    This study is aimed to derive effects of de-humidification and O{sub 2} direct injection in oxy-PC combustion system. Temperature distribution and flue gas composition were observed for various air and oxy-fuel conditions such as effect of various O{sub 2} concentration of total oxidant, O{sub 2} concentration of primary stream and O{sub 2} direct injection through 0-D heat and mass balance calculation and experiments in the oxy-PC combustion system of 0.3 MW scale in KITECH (Korea Institute of Industrial Technology). Flame attachment characteristic related to O{sub 2} direct injection was also observed experimentally. We found that FEGT (furnace exit gas temperature) of 100% de-humidification to oxidizer is lower than humidification condition; difference between two conditions is lower than 20 C in all cases. The efficiency changing of combustion was negligible in O{sub 2} direct injection. But O{sub 2} direct injection should be carefully designed to produce a stable flame.

  16. The effect of ethanol–diesel–biodiesel blends on combustion, performance and emissions of a direct injection diesel engine

    International Nuclear Information System (INIS)

    Labeckas, Gvidonas; Slavinskas, Stasys; Mažeika, Marius

    2014-01-01

    Highlights: • Ethanol–diesel–biodiesel blends were tested at the same air–fuel ratios and three ranges of speed. • The fuel oxygen mass content reflects changes in the autoignition delay more predictably than the cetane number does. • Using of composite blend E15B suggests the brake thermal efficiency the same as the normal diesel fuel. • Adding of ethanol to diesel fuel reduces the NO x emission for richer air–fuel mixtures at all engine speeds. • The ethanol effect on CO, HC emissions and smoke opacity depends on the air–fuel ratio and engine speed. - Abstract: The article presents the test results of a four-stroke, four-cylinder, naturally aspirated, DI 60 kW diesel engine operating on diesel fuel (DF) and its 5 vol% (E5), 10 vol% (E10), and 15 vol% (E15) blends with anhydrous (99.8%) ethanol (E). An additional ethanol–diesel–biodiesel blend E15B was prepared by adding the 15 vol% of ethanol and 5 vol% of biodiesel (B) to diesel fuel (80 vol%). The purpose of the research was to examine the influence of the ethanol and RME addition to diesel fuel on start of injection, autoignition delay, combustion and maximum heat release rate, engine performance efficiency and emissions of the exhaust when operating over a wide range of loads and speeds. The test results were analysed and compared with a base diesel engine running at the same air–fuel ratios of λ = 5.5, 3.0 and 1.5 corresponding to light, medium and high loads. The same air–fuel ratios predict that the energy content delivered per each engine cycle will be almost the same for various ethanol–diesel–biodiesel blends that eliminate some side effects and improve analyses of the test results. A new approach revealed an important role of the fuel bound oxygen, which reflects changes of the autoignition delay more predictably than the cetane number does. The influence of the fuel oxygen on maximum heat release rate, maximum combustion pressure, NO x , CO emissions and smoke opacity

  17. A volumetric flow sensor for automotive injection systems

    International Nuclear Information System (INIS)

    Schmid, U; Krötz, G; Schmitt-Landsiedel, D

    2008-01-01

    For further optimization of the automotive power train of diesel engines, advanced combustion processes require a highly flexible injection system, provided e.g. by the common rail (CR) injection technique. In the past, the feasibility to implement injection nozzle volumetric flow sensors based on the thermo-resistive measurement principle has been demonstrated up to injection pressures of 135 MPa (1350 bar). To evaluate the transient behaviour of the system-integrated flow sensors as well as an injection amount indicator used as a reference method, hydraulic simulations on the system level are performed for a CR injection system. Experimentally determined injection timings were found to be in good agreement with calculated values, especially for the novel sensing element which is directly implemented into the hydraulic system. For the first time pressure oscillations occurring after termination of the injection pulse, predicted theoretically, could be verified directly in the nozzle. In addition, the injected amount of fuel is monitored with the highest resolution ever reported in the literature

  18. A volumetric flow sensor for automotive injection systems

    Science.gov (United States)

    Schmid, U.; Krötz, G.; Schmitt-Landsiedel, D.

    2008-04-01

    For further optimization of the automotive power train of diesel engines, advanced combustion processes require a highly flexible injection system, provided e.g. by the common rail (CR) injection technique. In the past, the feasibility to implement injection nozzle volumetric flow sensors based on the thermo-resistive measurement principle has been demonstrated up to injection pressures of 135 MPa (1350 bar). To evaluate the transient behaviour of the system-integrated flow sensors as well as an injection amount indicator used as a reference method, hydraulic simulations on the system level are performed for a CR injection system. Experimentally determined injection timings were found to be in good agreement with calculated values, especially for the novel sensing element which is directly implemented into the hydraulic system. For the first time pressure oscillations occurring after termination of the injection pulse, predicted theoretically, could be verified directly in the nozzle. In addition, the injected amount of fuel is monitored with the highest resolution ever reported in the literature.

  19. On the effect of injection timing on the ignition of lean PRF/air/EGR mixtures under direct dual fuel stratification conditions

    KAUST Repository

    Luong, Minh Bau; Sankaran, Ramanan; Yu, Gwang Hyeon; Chung, Suk-Ho; Yoo, Chun Sang

    2017-01-01

    The ignition characteristics of lean primary reference fuel (PRF)/air/exhaust gas recirculation (EGR) mixture under reactivity-controlled compression ignition (RCCI) and direct duel fuel stratification (DDFS) conditions are investigated by 2-D direct numerical simulations (DNSs) with a 116-species reduced chemistry of the PRF oxidation. The 2-D DNSs of the DDFS combustion are performed by varying the injection timing of iso-octane (i-C8H18) with a pseudo-iso-octane (PC8H18) model together with a novel compression heating model to account for the compression heating and expansion cooling effects of the piston motion in an engine cylinder. The PC8H18 model is newly developed to mimic the timing, duration, and cooling effects of the direct injection of i-C8H18 onto a premixed background charge of PRF/air/EGR mixture with composition inhomogeneities. It is found that the RCCI combustion exhibits a very high peak heat release rate (HRR) with a short combustion duration due to the predominance of the spontaneous ignition mode of combustion. However, the DDFS combustion has much lower peak HRR and longer combustion duration regardless of the fuel injection timing compared to those of the RCCI combustion, which is primarily attributed to the sequential injection of i-C8H18. It is also found that the ignition delay of the DDFS combustion features a non-monotonic behavior with increasing fuel-injection timing due to the different effect of fuel evaporation on the low-, intermediate-, and high-temperature chemistry of the PRF oxidation. The budget and Damköhler number analyses verify that although a mixed combustion mode of deflagration and spontaneous ignition exists during the early phase of the DDFS combustion, the spontaneous ignition becomes predominant during the main combustion, and hence, the spread-out of heat release rate in the DDFS combustion is mainly governed by the direct injection process of i-C8H18. Finally, a misfire is observed for the DDFS combustion when

  20. On the effect of injection timing on the ignition of lean PRF/air/EGR mixtures under direct dual fuel stratification conditions

    KAUST Repository

    Luong, Minh Bau

    2017-06-10

    The ignition characteristics of lean primary reference fuel (PRF)/air/exhaust gas recirculation (EGR) mixture under reactivity-controlled compression ignition (RCCI) and direct duel fuel stratification (DDFS) conditions are investigated by 2-D direct numerical simulations (DNSs) with a 116-species reduced chemistry of the PRF oxidation. The 2-D DNSs of the DDFS combustion are performed by varying the injection timing of iso-octane (i-C8H18) with a pseudo-iso-octane (PC8H18) model together with a novel compression heating model to account for the compression heating and expansion cooling effects of the piston motion in an engine cylinder. The PC8H18 model is newly developed to mimic the timing, duration, and cooling effects of the direct injection of i-C8H18 onto a premixed background charge of PRF/air/EGR mixture with composition inhomogeneities. It is found that the RCCI combustion exhibits a very high peak heat release rate (HRR) with a short combustion duration due to the predominance of the spontaneous ignition mode of combustion. However, the DDFS combustion has much lower peak HRR and longer combustion duration regardless of the fuel injection timing compared to those of the RCCI combustion, which is primarily attributed to the sequential injection of i-C8H18. It is also found that the ignition delay of the DDFS combustion features a non-monotonic behavior with increasing fuel-injection timing due to the different effect of fuel evaporation on the low-, intermediate-, and high-temperature chemistry of the PRF oxidation. The budget and Damköhler number analyses verify that although a mixed combustion mode of deflagration and spontaneous ignition exists during the early phase of the DDFS combustion, the spontaneous ignition becomes predominant during the main combustion, and hence, the spread-out of heat release rate in the DDFS combustion is mainly governed by the direct injection process of i-C8H18. Finally, a misfire is observed for the DDFS combustion when

  1. Numerical Analysis of the Combustion and Emission Characteristics of Diesel Engines with Multiple Injection Strategies Using a Modified 2-D Flamelet Model

    Directory of Open Access Journals (Sweden)

    Gyujin Kim

    2017-08-01

    Full Text Available The multiple injection strategy has been widely used in diesel engines to reduce engine noise, NOx and soot formation. Fuel injection developments such as the common-rail and piezo-actuator system provide more precise control of the injection quantity and time under higher injection pressures. As various injection strategies become accessible, it is important to understand the interaction of each fuel stream and following combustion process under the multiple injection strategy. To investigate these complex processes quantitatively, numerical analysis using CFD is a good alternative to overcome the limitation of experiments. A modified 2-D flamelet model is further developed from previous work to model multi-fuel streams with higher accuracy. The model was validated under various engine operating conditions and captures the combustion and emissions characteristics as well as several parametric variations. The model is expected to be used to suggest advanced injection strategies in engine development processes.

  2. Combined effects of cooled EGR and a higher geometric compression ratio on thermal efficiency improvement of a downsized boosted spark-ignition direct-injection engine

    International Nuclear Information System (INIS)

    Su, Jianye; Xu, Min; Li, Tie; Gao, Yi; Wang, Jiasheng

    2014-01-01

    Highlights: • Experiments for the effects of cooled EGR and two compression ratios (CR) on fuel efficiency were conducted. • The mechanism for the observed fuel efficiency behaviors by cooled EGR and high CR was clarified. • Cooled EGR offers more fuel efficiency improvement than elevating CR from 9.3 to 10.9. • Combining 18–25% cooled EGR with 10.9 CR lead to 2.1–3.5% brake thermal efficiency improvements. - Abstract: The downsized boosted spark-ignition direct-injection (SIDI) engine has proven to be one of the most promising concepts to improve vehicle fuel economy. However, the boosted engine is typically designed at a lower geometric compression ratio (CR) due to the increased knock tendency in comparison to naturally aspirated engines, limiting the potential of improving fuel economy. On the other hand, cooled exhaust gas recirculation (EGR) has drawn attention due to the potential to suppress knock and improve fuel economy. Combing the effects of boosting, increased CR and cooled EGR to further improve fuel economy within acceptable knock tolerance has been investigated using a 2.0 L downsized boosted SIDI engine over a wide range of engine operating conditions from 1000 rpm to 3000 rpm at low to high loads. To clarify the mechanism of this complicated effects, the first law of thermodynamics analysis was conducted with the inputs from GT-Power® engine simulation. Experiment results indicate that cooled EGR provides more brake thermal efficiency improvement than increasing geometric CR from 9.3 to 10.9. The benefit of brake thermal efficiency from the higher CR is limited to low load conditions. The attributes for improving brake thermal efficiency by cooled EGR include reduced heat transfer loss, reduced pumping work and increased ratio of specific heats for all the engine operating conditions, as well as higher degree of constant volume heat release only for the knock-limited high load conditions. The combined effects of 18–25% cooled EGR

  3. Dry low NOx combustion system with pre-mixed direct-injection secondary fuel nozzle

    Science.gov (United States)

    Zuo, Baifang; Johnson, Thomas; Ziminsky, Willy; Khan, Abdul

    2013-12-17

    A combustion system includes a first combustion chamber and a second combustion chamber. The second combustion chamber is positioned downstream of the first combustion chamber. The combustion system also includes a pre-mixed, direct-injection secondary fuel nozzle. The pre-mixed, direct-injection secondary fuel nozzle extends through the first combustion chamber into the second combustion chamber.

  4. Knock Resistance and Fine Particle Emissions for Several Biomass-Derived Oxygenates in a Direct-Injection Spark-Ignition Engine

    Energy Technology Data Exchange (ETDEWEB)

    Ratcliff, Matthew A.; Burton, Jonathan; Sindler, Petr; Christensen, Earl; Fouts, Lisa; Chupka, Gina M.; McCormick, Robert L.

    2016-04-01

    Several high octane number oxygenates that could be derived from biomass were blended with gasoline and examined for performance properties and their impact on knock resistance and fine particle emissions in a single cylinder direct-injection spark-ignition engine. The oxygenates included ethanol, isobutanol, anisole, 4-methylanisole, 2-phenylethanol, 2,5-dimethyl furan, and 2,4-xylenol. These were blended into a summertime blendstock for oxygenate blending at levels ranging from 10 to 50 percent by volume. The base gasoline, its blends with p-xylene and p-cymene, and high-octane racing gasoline were tested as controls. Relevant gasoline properties including research octane number (RON), motor octane number, distillation curve, and vapor pressure were measured. Detailed hydrocarbon analysis was used to estimate heat of vaporization and particulate matter index (PMI). Experiments were conducted to measure knock-limited spark advance and particulate matter (PM) emissions. The results show a range of knock resistances that correlate well with RON. Molecules with relatively low boiling point and high vapor pressure had little effect on PM emissions. In contrast, the aromatic oxygenates caused significant increases in PM emissions (factors of 2 to 5) relative to the base gasoline. Thus, any effect of their oxygen atom on increasing local air-fuel ratio was outweighed by their low vapor pressure and high double-bond equivalent values. For most fuels and oxygenate blend components, PMI was a good predictor of PM emissions. However, the high boiling point, low vapor pressure oxygenates 2-phenylethanol and 2,4-xylenol produced lower PM emissions than predicted by PMI. This was likely because they did not fully evaporate and combust, and instead were swept into the lube oil.

  5. An experimental study on the effects of high-pressure and multiple injection strategies on DI diesel engine emissions

    KAUST Repository

    Yang, Seung Yeon; Chung, Suk-Ho

    2013-01-01

    An experimental study on effects of high-pressure injections in conjunction with split fuel injections were conducted on an AVL single cylinder DI diesel engine. Various injection schemes were studied through the use of an electronically controlled

  6. Premixed direct injection disk

    Science.gov (United States)

    York, William David; Ziminsky, Willy Steve; Johnson, Thomas Edward; Lacy, Benjamin; Zuo, Baifang; Uhm, Jong Ho

    2013-04-23

    A fuel/air mixing disk for use in a fuel/air mixing combustor assembly is provided. The disk includes a first face, a second face, and at least one fuel plenum disposed therebetween. A plurality of fuel/air mixing tubes extend through the pre-mixing disk, each mixing tube including an outer tube wall extending axially along a tube axis and in fluid communication with the at least one fuel plenum. At least a portion of the plurality of fuel/air mixing tubes further includes at least one fuel injection hole have a fuel injection hole diameter extending through said outer tube wall, the fuel injection hole having an injection angle relative to the tube axis. The invention provides good fuel air mixing with low combustion generated NOx and low flow pressure loss translating to a high gas turbine efficiency, that is durable, and resistant to flame holding and flash back.

  7. Effect of injection pressure on performance, emission, and combustion characteristics of diesel-acetylene-fuelled single cylinder stationary CI engine.

    Science.gov (United States)

    Srivastava, Anmesh Kumar; Soni, Shyam Lal; Sharma, Dilip; Jain, Narayan Lal

    2018-03-01

    In this paper, the effect of injection pressure on the performance, emission, and combustion characteristics of a diesel-acetylene fuelled single cylinder, four-stroke, direct injection (DI) diesel engine with a rated power of 3.5 kW at a rated speed of 1500 rpm was studied. Experiments were performed in dual-fuel mode at four different injection pressures of 180, 190, 200, and 210 bar with a flow rate of 120 LPH of acetylene and results were compared with that of baseline diesel operation. Experimental results showed that highest brake thermal efficiency of 27.57% was achieved at injection pressure of 200 bar for diesel-acetylene dual-fuel mode which was much higher than 23.32% obtained for baseline diesel. Carbon monoxide, hydrocarbon, and smoke emissions were also measured and found to be lower, while the NO x emissions were higher at 200 bar in dual fuel mode as compared to those in other injection pressures in dual fuel mode and also for baseline diesel mode. Peak cylinder pressure, net heat release rate, and rate of pressure rise were also calculated and were higher at 200 bar injection pressure in dual fuel mode.

  8. Emulation study on system characteristic of high pressure common-rail fuel injection system for marine medium-speed diesel engine

    Science.gov (United States)

    Wang, Qinpeng; Yang, Jianguo; Xin, Dong; He, Yuhai; Yu, Yonghua

    2018-05-01

    In this paper, based on the characteristic analyzing of the mechanical fuel injection system for the marine medium-speed diesel engine, a sectional high-pressure common rail fuel injection system is designed, rated condition rail pressure of which is 160MPa. The system simulation model is built and the performance of the high pressure common rail fuel injection system is analyzed, research results provide the technical foundation for the system engineering development.

  9. Minimally invasive injectable short nanofibers of poly(glycerol sebacate) for cardiac tissue engineering

    International Nuclear Information System (INIS)

    Ravichandran, Rajeswari; Venugopal, Jayarama Reddy; Sundarrajan, Subramanian; Mukherjee, Shayanti; Sridhar, Radhakrishnan; Ramakrishna, Seeram

    2012-01-01

    Myocardial tissue lacks the ability to appreciably regenerate itself following myocardial infarction (MI) which ultimately results in heart failure. Current therapies can only retard the progression of disease and hence tissue engineering strategies are required to facilitate the engineering of a suitable biomaterial to repair MI. The aim of this study was to investigate the in vitro properties of an injectable biomaterial for the regeneration of infarcted myocardium. Fabrication of core/shell fibers was by co-axial electrospinning, with poly(glycerol sebacate) (PGS) as core material and poly-l-lactic acid (PLLA) as shell material. The PLLA was removed by treatment of the PGS/PLLA core/shell fibers with DCM:hexane (2:1) to obtain PGS short fibers. These PGS short fibers offer the advantage of providing a minimally invasive injectable technique for the regeneration of infarcted myocardium. The scaffolds were characterized by SEM, FTIR and contact angle and cell–scaffold interactions using cardiomyocytes. The results showed that the cardiac marker proteins actinin, troponin, myosin heavy chain and connexin 43 were expressed more on short PGS fibers compared to PLLA nanofibers. We hypothesized that the injection of cells along with short PGS fibers would increase cell transplant retention and survival within the infarct, compared to the standard cell injection system. (paper)

  10. Experimental study of the effects of natural gas injection timing on the combustion performance and emissions of a turbocharged common rail dual-fuel engine

    International Nuclear Information System (INIS)

    Yang, Bo; Wei, Xing; Xi, Chengxun; Liu, Yifu; Zeng, Ke; Lai, Ming-Chia

    2014-01-01

    Highlights: • Natural gas injection timing has obvious effects on combustion of dual-fuel engine. • Combustion performance is improved with optimized natural gas injection timing. • BSHC and BSCO decreased with retarded natural gas injection timing at low load. • BSNO x increased at part load while reduced at high load with delay N.G. injection. • PM is very low and insensitive to the variation of natural gas injection timing. - Abstract: Natural gas combustion with pilot ignition has been considered to be one of the most promising ways to utilize natural gas in existing diesel engine without serious engine modification and it has been widely researched all over the world. In this study, three experiments of different loads (BMEP 0.240 MPa, 0.480 MPa and 0.767 MPa) were performed on a 2.8 L four-cylinder, natural gas manifold injection dual-fuel engine to investigate the effects of natural gas injection timing on engine combustion performance and emissions. The pilot injection parameters (pilot injection timing and pressure) and natural gas injection pressure remain constant at a speed of 1600 rpm in the experiment. The cylinder pressure, HRR, CoV imep , flame development duration, CA50 and brake thermal efficiency were analyzed. The results indicated that under low and part engine loads, the flame development duration and CA50 can be reduced by properly retarding natural gas injection timing, while the CoV imep increased with retarded natural gas injection timing. As a result, the brake thermal efficiency is increased and the combustion stability slightly deteriorates. Meanwhile, under low and part engine loads, PM emissions in the dual-fuel engine is much lower than that in conventional diesel engines, furthermore, at high load, the PM emissions are near zero. CO and HC emissions are reduced with retarded natural gas injection timing under low and part loads, however, NO x emissions are slightly increased. Under high load, the flame development duration

  11. A control-oriented approach to estimate the injected fuel mass on the basis of the measured in-cylinder pressure in multiple injection diesel engines

    International Nuclear Information System (INIS)

    Finesso, Roberto; Spessa, Ezio

    2015-01-01

    Highlights: • Control-oriented method to estimate injected quantities from in-cylinder pressure. • Able to calculate the injected quantities for multiple injection strategies. • Based on the inversion of a heat-release predictive model. • Low computational time demanding. - Abstract: A new control-oriented methodology has been developed to estimate the injected fuel quantities, in real-time, in multiple injection DI diesel engines on the basis of the measured in-cylinder pressure. The method is based on the inversion of a predictive combustion model that was previously developed by the authors, and that is capable of estimating the heat release rate and the in-cylinder pressure on the basis of the injection rate. The model equations have been rewritten in order to derive the injected mass as an output quantity, starting from use of the measured in-cylinder pressure as input. It has been verified that the proposed method is capable of estimating the injected mass of pilot pulses with an uncertainty of the order of ±0.15 mg/cyc, and the total injected mass with an uncertainty of the order of ±0.9 mg/cyc. The main sources of uncertainty are related to the estimation of the in-cylinder heat transfer and of the isentropic coefficient γ = c_p/c_v. The estimation of the actual injected quantities in the combustion chamber can represent a powerful means to diagnose the behavior of the injectors during engine operation, and offers the possibility of monitoring effects, such as injector ageing and injector coking, as well as of allowing an accurate control of the pilot injected quantities to be obtained; the latter are in fact usually characterized by a large dispersion, with negative consequences on the combustion quality and emission formation. The approach is characterized by a very low computational time, and is therefore suitable for control-oriented applications.

  12. A comparative analysis on combustion and emissions of some next generation higher-alcohol/diesel blends in a direct-injection diesel engine

    International Nuclear Information System (INIS)

    Rajesh Kumar, B.; Saravanan, S.; Rana, D.; Nagendran, A.

    2016-01-01

    Highlights: • Four higher-alcohols namely, iso-butanol, n-pentanol, n-hexanol and n-octanol, were used. • Iso-butanol/diesel blend presented longest ignition delay, highest peak pressures and peak heat release rates. • NOx emissions were high for n-pentanol/diesel and n-hexanol/diesel blends at high load conditions. • Smoke opacity is highest for n-octanol/diesel blend and lowest for iso-butanol/diesel blend. • HC emissions are high for iso-butanol/diesel and n-pentanol/diesel blends. - Abstract: Higher alcohols are attractive next generation biofuels that can be extracted from sugary, starchy and ligno-cellulosic biomass feedstocks using sustainable pathways. Their viability for use in diesel engines has greatly improved ever since extended bio-synthetic pathways have achieved substantial yields of these alcohols using engineered micro-organisms. This study sets out to compare and analyze the effects of some higher alcohol/diesel blends on combustion and emission characteristics of a direct-injection diesel engine. Four test fuels containing 30% by vol. of iso-butanol, n-pentanol, n-hexanol and n-octanol (designated as ISB30, PEN30, HEX30 and OCT30 respectively) in ultra-low sulfur diesel (ULSD) were used. Results indicated that ISB30 experienced longest ignition delay and produced highest peaks of pressure and heat release rates (HRR) compared to other higher-alcohol blends. The ignition delay, peak pressure and peak HRR are found to be in the order of (from highest to lowest): ISB30 > PEN30 > HEX30 > OCT30 > ULSD. The combustion duration (CD) for all test fuels is in the sequence (from shortest to longest): ISB30 OCT30 > HEX30 > PEN30 > ISB30. HC emissions are high for ISB30 and PEN30 while it decreased favorably for HEX30 and OCT30. It was of the order (from highest to lowest): ISB30 > PEN30 > ULSD > HEX30 > OCT30. CO emissions of the blends followed the trend of smoke emissions and remained lower than ULSD with the following order (from highest to

  13. Contingency power for a small turboshaft engine by using water injection into turbine cooling air

    Science.gov (United States)

    Biesiadny, Thomas J.; Klann, Gary A.

    1992-01-01

    Because of one-engine-inoperative (OEI) requirements, together with hot-gas reingestion and hot-day, high-altitude take-off situations, power augmentation for multiengine rotorcraft has always been of critical interest. However, power augmentation by using overtemperature at the turbine inlet will shorten turbine life unless a method of limiting thermal and mechanical stress is found. A possible solution involves allowing the turbine inlet temperature to rise to augment power while injecting water into the turbine cooling air to limit hot-section metal temperatures. An experimental water injection device was installed in an engine and successfully tested. Although concern for unprotected subcomponents in the engine hot section prevented demonstration of the technique's maximum potential, it was still possible to demonstrate increases in power while maintaining nearly constant turbine rotor blade temperature.

  14. An injectable calcium phosphate-alginate hydrogel-umbilical cord mesenchymal stem cell paste for bone tissue engineering

    Science.gov (United States)

    Zhao, Liang; Weir, Michael D.; Xu, Hockin H. K.

    2010-01-01

    The need for bone repair has increased as the population ages. Stem cell-scaffold approaches hold immense promise for bone tissue engineering. However, currently, preformed scaffolds for cell delivery have drawbacks including the difficulty to seed cells deep into the scaffold, and inability for injection in minimally invasive surgeries. Current injectable polymeric carriers and hydrogels are too weak for load-bearing orthopedic application. The objective of this study was to develop an injectable and mechanically-strong stem cell construct for bone tissue engineering. Calcium phosphate cement (CPC) paste was combined with hydrogel microbeads encapsulating human umbilical cord mesenchymal stem cells (hUCMSCs). The hUCMSC-encapsulating composite paste was fully injectable under small injection forces. Cell viability after injection matched that in hydrogel without CPC and without injection. Mechanical properties of the construct matched the reported values of cancellous bone, and were much higher than previous injectable polymeric and hydrogel carriers. hUCMSCs in the injectable constructs osteodifferentiated, yielding high alkaline phosphatase, osteocalcin, collagen type I, and osterix gene expressions at 7 d, which were 50–70 fold higher than those at 1 d. Mineralization by the hUCMSCs at 14 d was 100-fold that at 1 d. In conclusion, a fully-injectable, mechanically-strong, stem cell-CPC scaffold construct was developed. The encapsulated hUCMSCs remained viable, osteodifferentiated, and synthesized bone minerals. The new injectable stem cell construct with load-bearing capability may enhance bone regeneration in minimally-invasive and other orthopedic surgeries. PMID:20570346

  15. International Journal of Engineering, Science and Technology - Vol ...

    African Journals Online (AJOL)

    Effect of injection timing and injection pressure on the performance of biodiesel ester of hongeoil fuelled common rail direct injection (CRDI) engine · EMAIL FREE ... Comparison of performance and emission characteristics of diesel and diesel-water blend under varying injection timings · EMAIL FREE FULL TEXT EMAIL ...

  16. Engineering of the divertor injection tokamak experiment (DITE)

    International Nuclear Information System (INIS)

    Plummer, K.M.; Bayes, D.V.; Bell, D.; Burt, J.; Galloway, F.; Sanders, B.C.; Skelton, D.E.; Varley, G.L.

    1976-01-01

    The DITE assembly has been constructed to study the effect of powerful neutral injection and the use of magnetic divertors in Tokamak systems. In addition, the plasma is stabilized by a position controlled feed-back vertical field system developed from results on the CLEO experiment, and added to DITE later in the design stage. The machine is designed for an ultimate plasma current of 340 kA, having a minor radius of 23 cm at q = 2, on a major radius of 113 cm. The 28 kG Bphi field, from 16 liquid nitrogen cooled coils has a 2% ripple at the edge of the plasma. The divertor is a ''bundle'' type, the present design of which is limited to operating in a Bphi field of 18 kG. Neutral Injection, initially by two, and ultimately by four injectors, is intended to supply about 1,500 kW of beam power. The engineering is now complete and the machine commissioned; this paper describes the up-to-date design of the machine and includes some of our experiences during design, construction and commissioning

  17. Effects of injection timing, before and after top dead center on the propulsion and power in a diesel engine

    Directory of Open Access Journals (Sweden)

    Nader Raeie

    2014-06-01

    Full Text Available It is well known that injection strategies including the injection timing and pressure play the most important role in determining engine performance, especially in pollutant emissions. However, the injection timing and pressure quantitatively affect the performance of diesel engine with a turbo charger are not well understood. In this paper, the fire computational fluid dynamics (CFD code with an improved spray model has been used to simulate the spray and combustion processes of diesel with early and late injection timings and six different injection pressure (from 275 bar to 1000 bar. It has been concluded that the use of early injection provides lower soot and higher NOx emissions than the late injection. In this study, it has been tried using the change of fuel injection time at these two next steps: before top dead center (BTDC and after top dead center (ATDC in order to achieving optimum emission and power in a specific point.

  18. The Use of Large Valve Overlap in Scavenging a Supercharged Spark-ignition Engine Using Fuel Injection

    Science.gov (United States)

    Schey, Oscar W; Young, Alfred W

    1932-01-01

    This investigation was conducted to determine the effect of more complete scavenging on the full throttle power and the fuel consumption of a four-stroke-cycle engine. The NACA single-cylinder universal test engine equipped with both a fuel-injection system and a carburetor was used. The engine was scavenged by using a large valve overlap and maintaining a pressure in the inlet manifold of 2 inches of mercury above atmospheric. The maximum valve overlap used was 112 degrees. Tests were conducted for a range of compression ratios from 5.5 to 8.5. Except for variable speed tests, all tests were conducted at an engine speed of 1,500 r.p.m. The results of the tests show that the clearance volume of an engine can be scavenged by using a large valve overlap and about 2 to 5 inches of mercury pressure difference between the inlet and exhaust valve. With a fuel-injection system when the clearance volume was scavenged, a b.m.e.p. of over 185 pounds per square inch and a fuel consumption of 9.45 pound per brake horsepower per hour were obtained with a 6.5 compression ratio. An increase of approximately 10 pounds per square inch b.m.e.p. was obtained with a fuel-injection system over that with a carburetor.

  19. Alternative Fuels DISI Engine Research ? Autoignition Metrics.

    Energy Technology Data Exchange (ETDEWEB)

    Sjoberg, Carl Magnus Goran [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Vuilleumier, David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2018-02-01

    Improved engine efficiency is required to comply with future fuel economy standards. Alternative fuels have the potential to enable more efficient engines while addressing concerns about energy security. This project contributes to the science base needed by industry to develop highly efficient direct injection spark igniton (DISI) engines that also beneficially exploit the different properties of alternative fuels. Here, the emphasis is on quantifying autoignition behavior for a range of spark-ignited engine conditions, including directly injected boosted conditions. The efficiency of stoichiometrically operated spark ignition engines is often limited by fuel-oxidizer end-gas autoignition, which can result in engine knock. A fuel’s knock resistance is assessed empirically by the Research Octane Number (RON) and Motor Octane Number (MON) tests. By clarifying how these two tests relate to the autoignition behavior of conventional and alternative fuel formulations, fuel design guidelines for enhanced engine efficiency can be developed.

  20. An Optical Method for Measuring Injection Timing in Diesel Engines, Using a Single Port

    Science.gov (United States)

    2014-09-01

    injection, naturally aspirated marine diesel engine with mechanical unit injectors and showed satisfactory results with blends ranging from 25% HRD/75... injector technology, they further concluded that the mechanical unit injectors found throughout the naval fleet and on the Detroit Diesel 3–53 in the...injection timing in a pump-line- nozzle system of blending Fischer- Tropsch derived diesel fuel with low sulfur, ultra-low sulfur and biodiesel fuels. The

  1. Separating inverse spin Hall voltage and spin rectification voltage by inverting spin injection direction

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Wenxu, E-mail: xwzhang@uestc.edu.cn; Peng, Bin; Han, Fangbin; Wang, Qiuru; Zhang, Wanli [State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054 (China); Soh, Wee Tee; Ong, Chong Kim [Center for Superconducting and Magnetic Materials, Department of Physics, National University of Singapore, 2 Science Drive 3, Singapore 117551 (Singapore)

    2016-03-07

    We develop a method for universally resolving the important issue of separating the inverse spin Hall effect (ISHE) from the spin rectification effect (SRE) signal. This method is based on the consideration that the two effects depend on the spin injection direction: The ISHE is an odd function of the spin injection direction while the SRE is independent on it. Thus, the inversion of the spin injection direction changes the ISHE voltage signal, while the SRE voltage remains. It applies generally to analyzing the different voltage contributions without fitting them to special line shapes. This fast and simple method can be used in a wide frequency range and has the flexibility of sample preparation.

  2. Multidimensional modeling of the effect of fuel injection pressure on temperature distribution in cylinder of a turbocharged DI diesel engine

    Directory of Open Access Journals (Sweden)

    Sajjad Emami

    2013-06-01

    Full Text Available In this study, maintaining a constant fuel rate, injection pressure of 275 bar to 1000 bar (275×102 kPa to 1000×102 kPa, has been changed. Effect of injection pressure, the pressure inside the cylinder on the free energy, power, engine indicators, particularly indicators of fuel consumption, pollutants and their effects on parameters affecting the output of the engine combustion chamber have been studied in droplet diameter. Finally, the effects of fuel mixture equivalence, Cantor temperature, soot and NOx due to the increase of injection pressure, engine efficiency and emissions have been examined.

  3. Extending Lean and Exhaust Gas Recirculation-Dilute Operating Limits of a Modern Gasoline Direct-Injection Engine Using a Low-Energy Transient Plasma Ignition System

    Energy Technology Data Exchange (ETDEWEB)

    Sevik, James; Wallner, Thomas; Pamminger, Michael; Scarcelli, Riccardo; Singleton, Dan; Sanders, Jason

    2016-05-24

    The efficiency improvement and emissions reduction potential of lean and exhaust gas recirculation (EGR)-dilute operation of spark-ignition gasoline engines is well understood and documented. However, dilute operation is generally limited by deteriorating combustion stability with increasing inert gas levels. The combustion stability decreases due to reduced mixture flame speeds resulting in significantly increased combustion initiation periods and burn durations. A study was designed and executed to evaluate the potential to extend lean and EGR-dilute limits using a low-energy transient plasma ignition system. The low-energy transient plasma was generated by nanosecond pulses and its performance compared to a conventional transistorized coil ignition (TCI) system operated on an automotive, gasoline direct-injection (GDI) single-cylinder research engine. The experimental assessment was focused on steady-state experiments at the part load condition of 1500 rpm 5.6 bar indicated mean effective pressure (IMEP), where dilution tolerance is particularly critical to improving efficiency and emission performance. Experimental results suggest that the energy delivery process of the low-energy transient plasma ignition system significantly improves part load dilution tolerance by reducing the early flame development period. Statistical analysis of relevant combustion metrics was performed in order to further investigate the effects of the advanced ignition system on combustion stability. Results confirm that at select operating conditions EGR tolerance and lean limit could be improved by as much as 20% (from 22.7 to 27.1% EGR) and nearly 10% (from λ = 1.55 to 1.7) with the low-energy transient plasma ignition system.

  4. The injection equipment of future high-speed DI diesel engines with respect to power and pollution requirements

    Energy Technology Data Exchange (ETDEWEB)

    Dolenc, A. (Monobloc Dieselmotoren GmbH, Vienna (AT))

    1990-01-01

    The development of high specific output DI diesel engines started at the low-speed end some 50 years ago primarily for marine and traction applications. Movement towards the high-speed end has been slow but steady with the majority of truck engines being very conservatively rated. There has been recent major effort on the automotive car and light commercial vehicle diesel application leading to lightweight DI diesel engines with an engine speed of 4000-5000 r/min and a rated power of 50 kW/litre displacement. These are expected to be on the market in a short period of time. The key point of this development has been the injection equipment including combustion control. In this area the use of modulated injection has the possibility of solving power and pollution requirements. (author).

  5. Engineering bone regeneration with novel cell-laden hydrogel microfiber-injectable calcium phosphate scaffold

    Energy Technology Data Exchange (ETDEWEB)

    Song, Yang [Department of Prosthodontics, Guanghua School of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, Guangdong (China); Department of Endodontics, Periodontics and Prosthodontics, University of Maryland School of Dentistry, Baltimore, MD 21201 (United States); Zhang, Chi [State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan 610041 (China); Department of Endodontics, Periodontics and Prosthodontics, University of Maryland School of Dentistry, Baltimore, MD 21201 (United States); Wang, Ping, E-mail: dentistping@gmail.com [Department of Endodontics, Periodontics and Prosthodontics, University of Maryland School of Dentistry, Baltimore, MD 21201 (United States); Wang, Lin [Department of Endodontics, Periodontics and Prosthodontics, University of Maryland School of Dentistry, Baltimore, MD 21201 (United States); VIP Integrated Department, School and Hospital of Stomatology, Jilin University, Changchun, Jilin 130011 (China); Bao, Chunyun [State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan 610041 (China); Department of Endodontics, Periodontics and Prosthodontics, University of Maryland School of Dentistry, Baltimore, MD 21201 (United States); Weir, Michael D.; Reynolds, Mark A. [Department of Endodontics, Periodontics and Prosthodontics, University of Maryland School of Dentistry, Baltimore, MD 21201 (United States); Ren, Ke [Department of Neural and Pain Sciences, School of Dentistry, Program in Neuroscience, University of Maryland, Baltimore, MD 21201 (United States); Zhao, Liang, E-mail: lzhaonf@126.com [Department of Endodontics, Periodontics and Prosthodontics, University of Maryland School of Dentistry, Baltimore, MD 21201 (United States); Department of Orthopaedic Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong 510515 (China); and others

    2017-06-01

    Cell-based tissue engineering is promising to create living functional tissues for bone regeneration. The implanted cells should be evenly distributed in the scaffold, be fast-released to the defect and maintain high viability in order to actively participate in the regenerative process. Herein, we report an injectable calcium phosphate cement (CPC) scaffold containing cell-encapsulating hydrogel microfibers with desirable degradability that could deliver cells in a timely manner and maintain cell viability. Microfibers were synthesized using partially-oxidized alginate with various concentrations (0–0.8%) of fibrinogen to optimize the degradation rate of the alginate-fibrin microfibers (Alg-Fb MF). A fibrin concentration of 0.4% in Alg-Fb MF resulted in the greatest enhancement of cell migration, release and proliferation. Interestingly, a significant amount of cell–cell contact along the long-axis of the microfibers was established in Alg-0.4%Fb MF as early as day 2. The injectable tissue engineered construct for bone reconstruct was fabricated by mixing the fast-degradable Alg-0.4%Fb MF with CPC paste at 1:1 volume ratio. In vitro study showed that cells re-collected from the construct maintained good viability and osteogenic potentials. In vivo study demonstrated that the hBMSC-encapsulated CPC-MF tissue engineered construct displayed a robust capacity for bone regeneration. At 12 weeks after implantation, osseous bridge in the rat mandibular defect was observed in CPC-MF-hBMSCs group with a new bone area fraction of (42.1 ± 7.8) % in the defects, which was > 3-fold that of the control group. The novel tissue-engineered construct presents an excellent prospect for a wide range of dental, craniofacial and orthopedic applications. - Highlights: • Microfibers protected cells during CPC mixing and injection, and supported the viability, migration and differentiation of encapsulated cells. • Cells re-collected from the construct maintained good viability

  6. Engineering bone regeneration with novel cell-laden hydrogel microfiber-injectable calcium phosphate scaffold

    International Nuclear Information System (INIS)

    Song, Yang; Zhang, Chi; Wang, Ping; Wang, Lin; Bao, Chunyun; Weir, Michael D.; Reynolds, Mark A.; Ren, Ke; Zhao, Liang

    2017-01-01

    Cell-based tissue engineering is promising to create living functional tissues for bone regeneration. The implanted cells should be evenly distributed in the scaffold, be fast-released to the defect and maintain high viability in order to actively participate in the regenerative process. Herein, we report an injectable calcium phosphate cement (CPC) scaffold containing cell-encapsulating hydrogel microfibers with desirable degradability that could deliver cells in a timely manner and maintain cell viability. Microfibers were synthesized using partially-oxidized alginate with various concentrations (0–0.8%) of fibrinogen to optimize the degradation rate of the alginate-fibrin microfibers (Alg-Fb MF). A fibrin concentration of 0.4% in Alg-Fb MF resulted in the greatest enhancement of cell migration, release and proliferation. Interestingly, a significant amount of cell–cell contact along the long-axis of the microfibers was established in Alg-0.4%Fb MF as early as day 2. The injectable tissue engineered construct for bone reconstruct was fabricated by mixing the fast-degradable Alg-0.4%Fb MF with CPC paste at 1:1 volume ratio. In vitro study showed that cells re-collected from the construct maintained good viability and osteogenic potentials. In vivo study demonstrated that the hBMSC-encapsulated CPC-MF tissue engineered construct displayed a robust capacity for bone regeneration. At 12 weeks after implantation, osseous bridge in the rat mandibular defect was observed in CPC-MF-hBMSCs group with a new bone area fraction of (42.1 ± 7.8) % in the defects, which was > 3-fold that of the control group. The novel tissue-engineered construct presents an excellent prospect for a wide range of dental, craniofacial and orthopedic applications. - Highlights: • Microfibers protected cells during CPC mixing and injection, and supported the viability, migration and differentiation of encapsulated cells. • Cells re-collected from the construct maintained good viability

  7. Effects of Injection Scheme on Rotating Detonation Engine Operation

    Science.gov (United States)

    Chacon, Fabian; Duvall, James; Gamba, Mirko

    2017-11-01

    In this work, we experimentally investigate the operation and performance characteristics of a rotating detonation engine (RDE) operated with different fuel injection schemes and operating conditions. In particular, we investigate the detonation and operation characteristics produced with an axial flow injector configuration and semi-impinging injector configurations. These are compared to the characteristics produced with a canonical radial injection system (AFRL injector). Each type produces a different flowfield and mixture distribution, leading to a different detonation initiation, injector dynamic response, and combustor pressure rise. By using a combination of diagnostics, we quantify the pressure loses and gains in the system, the ability to maintain detonation over a range of operating points, and the coupling between the detonation and the air/fuel feed lines. We particularly focus on how this coupling affects both the stability and the performance of the detonation wave. This work is supported by the DOE/UTSR program under project DE-FE0025315.

  8. Effect of Biodiesel Fuel Injection Timing and Venture for Gaseous Fuel Induction on the Performance, Emissions and Combustion Characteristics of Dual Fuel Engine

    Directory of Open Access Journals (Sweden)

    Mallikarjun Bhovi

    2018-02-01

    Full Text Available Advancing or retarding pilot fuel injection timing in a diesel engine provided with either conventional mechanical fuel injection (CMFIS or high pressure injection as in common rail fuel injection (CRDI systems can significantly affect its performance and tail pipe emissions. Performance of diesel engine when fueled with various biofuels as well as gaseous fuels tends to vary with subsequent changes in pilot fuel injection timings. Biodiesel derived from rubber seed oil called Rubber Seed Oil Methyl Ester (RuOME and hydrogen (H2 and hydrogen enriched compressed natural gas called (HCNG both being renewable fuels when used in diesel engines modified to operate in dual fuel mode can provide complete replacement for fossil diesel. In the present study, effect of injection timings and venture design for gas mixing on the performance, combustion and emission characteristics of dual fuel engine fitted with both CMFIS and CRDI injection systems and operated on RuOME and HCNG/hydrogen has been investigated. Results showed that high pressure CRDI assisted injection of RuOME with optimized mixing chamber (carburetor for hydrogen induction in dual fuel engine performed improved compared to that with CMFIS. In addition, for the same fuel combinations, CRDI resulted in lower biodiesel consumption, lower carbon monoxide (BSCO and hydrocarbon (BSHC emissions and increased NOx emissions than CMFIS operation.

  9. 77 FR 23637 - Airworthiness Directives; Pratt & Whitney Division Turbofan Engines

    Science.gov (United States)

    2012-04-20

    ... Airworthiness Directives; Pratt & Whitney Division Turbofan Engines AGENCY: Federal Aviation Administration (FAA... directive (AD) for certain Pratt & Whitney Division PW4000-94'' and PW4000-100'' turbofan engines having a...-flight engine shutdowns, in certain PW4000-94'' and PW4000-100'' turbofan engines. Pratt & Whitney's...

  10. Spray characterization of a piezo pintle-type injector for gasoline direct injection engines

    Science.gov (United States)

    Nouri, J. M.; Hamid, M. A.; Yan, Y.; Arcoumanis, C.

    2007-10-01

    The sprays from a pintle-type nozzle injected into a constant volume chamber have been visualised by a high resolution CCD camera and quantified in terms of droplet velocity and diameter with a 2-D phase Doppler anemometry (PDA) system at an injection pressure of 200 bar and back-pressures varying from atmospheric to 12 bar. Spray visualization illustrated that the spray was string-structured, that the location of the strings remained constant from one injection to the next and that the spray structure was unaffected by back pressure. The overall spray cone angle was also stable and independent of back pressure whose effect was to reduce the spray tip penetration so that the averaged vertical spray tip velocity was reduced by 37% when the back-pressure increased from 1 to 12 bar. Detailed PDA measurements were carried out under atmospheric conditions at 2.5 and 10 mm from the injector exit with the results providing both the temporal and the spatial velocity and size distributions of the spray droplets. The maximum axial mean droplet velocity was 155 m/s at 2.5 mm from the injector which was reduced to 140 m/s at z = 10 mm. The string spacing determined from PDA measurements was around 0.375 mm and 0.6 mm at z=2.5 and 10 mm, respectively. The maximum mean droplet diameter was found to be in the core of the strings with values up to 40 μm at z=2.5 mm reducing to 20 μm at z=10 mm.

  11. Spray characterization of a piezo pintle-type injector for gasoline direct injection engines

    International Nuclear Information System (INIS)

    Nouri, J M; Hamid, M A; Yan, Y; Arcoumanis, C

    2007-01-01

    The sprays from a pintle-type nozzle injected into a constant volume chamber have been visualised by a high resolution CCD camera and quantified in terms of droplet velocity and diameter with a 2-D phase Doppler anemometry (PDA) system at an injection pressure of 200 bar and back-pressures varying from atmospheric to 12 bar. Spray visualization illustrated that the spray was string-structured, that the location of the strings remained constant from one injection to the next and that the spray structure was unaffected by back pressure. The overall spray cone angle was also stable and independent of back pressure whose effect was to reduce the spray tip penetration so that the averaged vertical spray tip velocity was reduced by 37% when the back-pressure increased from 1 to 12 bar. Detailed PDA measurements were carried out under atmospheric conditions at 2.5 and 10 mm from the injector exit with the results providing both the temporal and the spatial velocity and size distributions of the spray droplets. The maximum axial mean droplet velocity was 155 m/s at 2.5 mm from the injector which was reduced to 140 m/s at z = 10 mm. The string spacing determined from PDA measurements was around 0.375 mm and 0.6 mm at z=2.5 and 10 mm, respectively. The maximum mean droplet diameter was found to be in the core of the strings with values up to 40 μm at z=2.5 mm reducing to 20 μm at z=10 mm

  12. Modulated diesel fuel injection strategy for efficient-clean utilization of low-grade biogas

    International Nuclear Information System (INIS)

    Wang, Xiaole; Qian, Yong; Zhou, Qiyan; Lu, Xingcai

    2016-01-01

    Highlights: • Influences of direct injection strategy on biogas RCCI mode are researched. • Excessive early pilot injection timing leads to the retard of combustion. • Overall indicated thermal efficiency of low-grade biogas can be higher than 40%. • Pilot injection timing has strong influence on particle size distribution. • Composition of biogas has a great influence on the gas emissions. - Abstract: Recently, as a kind of renewable fuel, low-grade biogas has been researched to apply in internal combustion engine. In this paper, an experimental study was conducted to study the influence of injection strategies on the efficient utilization of low-grade biogas in Reactivity Controlled Compression Ignition (RCCI) mode with port fuel injection of biogas and in-cylinder direct injection of diesel based on a modified electronic controlled high-pressure directly injected compression ignition engine. Considered the high proportion of inert gas in biogas, a four-components simulated gas (H_2:CO:CH_4:N_2 = 5:40:5:50 vol%) has been selected as test fuels to simulate biogas. The effects of several injection control parameters such as pilot injection timing, main injection timing, common rail pressure and pilot injection ratio on the combustion and emissions are analyzed in detail. The research demonstrates that the main injection timing can effectively control the combustion phase and excessive early pilot injection timing leads to retard of combustion. CO emissions are relatively high due to homogenous charge of biogas. NOx and smoke emissions can be effectively controlled. In RCCI mode, the indicated thermal efficiency of biogas/diesel can reach 40%.

  13. A Study of Performance Output of a Multivane Air Engine Applying Optimal Injection and Vane Angles

    Directory of Open Access Journals (Sweden)

    Bharat Raj Singh

    2012-01-01

    Full Text Available This paper presents a new concept of the air engine using compressed air as the potential power source for motorbikes, in place of an internal combustion engine. The motorbike is proposed to be equipped with an air engine, which transforms the energy of the compressed air into mechanical motion energy. A mathematical model is presented here, and performance evaluation is carried out on an air-powered novel air turbine engine. The maximum power output is obtained as 3.977 kW (5.50 HP at the different rotor to casing diameter ratios, optimal injection angle 60°, vane angle 45° for linear expansion (i.e., at minimum air consumption when the casing diameter is kept 100 mm, at injection pressure 6 bar (90 psi and speed of rotation 2500 rpm. A prototype air engine is built and tested in the laboratory. The experimental results are also seen much closer to the analytical values, and the performance efficiencies are recorded around 70% to 95% at the speed of rotation 2500–3000 rpm.

  14. Collective properties of injection-induced earthquake sequences: 1. Model description and directivity bias

    Science.gov (United States)

    Dempsey, David; Suckale, Jenny

    2016-05-01

    Induced seismicity is of increasing concern for oil and gas, geothermal, and carbon sequestration operations, with several M > 5 events triggered in recent years. Modeling plays an important role in understanding the causes of this seismicity and in constraining seismic hazard. Here we study the collective properties of induced earthquake sequences and the physics underpinning them. In this first paper of a two-part series, we focus on the directivity ratio, which quantifies whether fault rupture is dominated by one (unilateral) or two (bilateral) propagating fronts. In a second paper, we focus on the spatiotemporal and magnitude-frequency distributions of induced seismicity. We develop a model that couples a fracture mechanics description of 1-D fault rupture with fractal stress heterogeneity and the evolving pore pressure distribution around an injection well that triggers earthquakes. The extent of fault rupture is calculated from the equations of motion for two tips of an expanding crack centered at the earthquake hypocenter. Under tectonic loading conditions, our model exhibits a preference for unilateral rupture and a normal distribution of hypocenter locations, two features that are consistent with seismological observations. On the other hand, catalogs of induced events when injection occurs directly onto a fault exhibit a bias toward ruptures that propagate toward the injection well. This bias is due to relatively favorable conditions for rupture that exist within the high-pressure plume. The strength of the directivity bias depends on a number of factors including the style of pressure buildup, the proximity of the fault to failure and event magnitude. For injection off a fault that triggers earthquakes, the modeled directivity bias is small and may be too weak for practical detection. For two hypothetical injection scenarios, we estimate the number of earthquake observations required to detect directivity bias.

  15. The effect of injection timing on energy and exergy analysis of a diesel engine with biodiesel fuel

    Directory of Open Access Journals (Sweden)

    A Farhadi

    2017-05-01

    Full Text Available Introduction Nowadays, due to higher environmental pollution and decreasing fossil fuels many countries make decisions to use renewable fuels and restrict using of fossil fuels. Renewable fuels generally produce from biological sources. Biodiesel is an alternative diesel fuel derived from the transesterification of vegetable oils, animal fats, or waste frying oils. Considering the differences between diesel and biodiesel fuels, engine condition should be modified based on the fuel or fuel blends to achieve optimum performance. One of the simplest and yet the most widely used models is the thermodynamic model. After verification of the data obtained by model with experimental data it is possible to generalize the extracted data to an unlimited number of functional conditions or unlimited number of fuel types which saves time and reduces costs for experimental engine tests. Using the second law of thermodynamics, it is possible to calculate and analyze the exergy of the engine.4 Materials and Methods In this work, the zero-dimensional model was used to account for internal energy variations, pressure work, heat transfer losses to the solid walls and heat release. The applied assumptions include: The cylinder mixture temperature, pressure and composition were assumed uniform throughout the cylinder. Furthermore, the one-zone thermodynamic model assumes instantaneous mixing between the burned and unburned gases. The cylinder gases were assumed to behave as an ideal gas mixture, Gas properties, include enthalpy, internal energy modeled using polynomial equations associated with temperature. In this research, the equations 1 to 20 were used in Fortran programming language. The results of incylinder pressure obtained by the model were validated by the results of experimental test of OM314 engine. Then the effects of injection timing on Energy and Exergy of the engine were analyzed for B20 fuel. Results and Discussion Comparing the results of the model

  16. Advanced rotary engines

    Science.gov (United States)

    Jones, C.

    1983-01-01

    The broad objectives of this paper are the following: (1) to summarize the Curtiss-Wright design, development and field testing background in the area of rotary aircraft engines; (2) to briefly summarize past activity and update development work in the area of stratified charge rotary combustion engines; and (3) to discuss the development of a high-performance direct injected unthrottled stratified charge rotary combustion aircraft engine. Efficiency improvements through turbocharging are also discussed.

  17. Behaviour analysis of the fuel injected in the intake manifold of port-injected spark ignition engines: modeling and experimental validation; Analyse du comportement du carburant injecte dans les conduits d`admission des moteurs a allumage commande a injection multipoint: modelisation et validation experimentale

    Energy Technology Data Exchange (ETDEWEB)

    Sches, C

    1999-01-27

    In order to limit pollutant emissions resulting from transient engine operation, the mastering of mixture formation is essential. In this context, an interactive work was undertaken between a modeling job and an experimental study, to get better understanding of the mechanisms of fuel dynamic behavior in the intake manifold of port-injected spark-ignition engines. The experimental study, elaborated thanks to experimental designs, showed out two essential factors: injection timing and coolant liquid temperature, which act on the fuel dynamic behavior through a second order filter. Then, a phenomenological modeling was established and validated, to analyze the various phenomena influencing mixture formation and to calculate the air/fuel ratio evolutions during transient operation. This program uses the results of a 3D model describing the fuel spray transportation, evaporation and impact on the port walls. The calculation does not need any boundary conditions and the running times are vary satisfactory. We showed that a correct description of the liquid fuel film was necessary to get good prediction of the mixture fuel/air ratio. The spray modeling, which is necessary, can however be kept simple. Future work may develop either in the engine control filed (injection strategies development, optimization of the injection system configuration, ...), or in the theoretical field (better modeling of fuel film displacement or of secondary atomization of the fuel on the intake valve). (author) 79 refs.

  18. Extraordinary mullet growth through direct injection of foreign DNA ...

    African Journals Online (AJOL)

    The present study aims to produce a genetically modified grey mullet, Mugil cephalus, with accelerated growth through direct injection of foreign DNA isolated from the liver of shark (Squalus acanthias L.) or African catfish (Clarias gariepinus) into muscles of fingerlings fish at the dose of 40 μg/fish. The results show a ...

  19. Effects of Injection Rate Profile on Combustion Process and Emissions in a Diesel Engine

    Directory of Open Access Journals (Sweden)

    Fuqiang Bai

    2017-01-01

    Full Text Available When multi-injection is implemented in diesel engine via high pressure common rail injection system, changed interval between injection pulses can induce variation of injection rate profile for sequential injection pulse, though other control parameters are the same. Variations of injection rate shape which influence the air-fuel mixing and combustion process will be important for designing injection strategy. In this research, CFD numerical simulations using KIVA-3V were conducted for examining the effects of injection rate shape on diesel combustion and emissions. After the model was validated by experimental results, five different shapes (including rectangle, slope, triangle, trapezoid, and wedge of injection rate profiles were investigated. Modeling results demonstrate that injection rate shape can have obvious influence on heat release process and heat release traces which cause different combustion process and emissions. It is observed that the baseline, rectangle (flat, shape of injection rate can have better balance between NOx and soot emissions than the other investigated shapes. As wedge shape brings about the lowest NOx emissions due to retarded heat release, it produces the highest soot emissions among the five shapes. Trapezoid shape has the lowest soot emissions, while its NOx is not the highest one. The highest NOx emissions were produced by triangle shape due to higher peak injection rate.

  20. Prediction of major pollutants emission in direct injection dual-fuel diesel and natural-gas engines

    International Nuclear Information System (INIS)

    Pirouzpanah, V.; Kashani, B.O.

    2000-01-01

    The dual-fuel diesel engine is a conventional diesel engine in which much of the energy released, hence power, comes from the combustion of gaseous fuel such as natural gas. The exhaust emission characteristics of the dual-fuel diesel engine needs further refinements, particularly in terms of reduction of Unburnt Hydrocarbons and Carbon Monoxide (CO) emission, because the concentration of these pollutants are higher than that of the baseline diesel engine. Furthermore, the combustion process in a typical dual-fuel diesel engine tends to be complex, showing combination of the problems encountered both in diesel and spark ignition engines. In this work, a computer code has been modified for simulation of dual-fuel diesel engine combustion process. This model simulates dual-fuel diesel engine combustion by using a Multi-Zone Combustion Model for diesel pilot jet combustion and a conventional spark ignition combustion model for modelling of combustion of premixed gas/air charge. Also, in this model, there are four submodels for prediction of major emission pollutants such as: Unburnt Hydrocarbons, No, Co and soot which are emitted from dual-fuel diesel engine. For prediction of formation and oxidation rates of pollutants, relevant s conventional kinetically-controlled mechanisms and mass balances are used. the model has been verified by experimental data obtained from a heavy-duty truck and bus diesel engines. The comparison shows that, there exist good agreements between the experimental and predicted results from the dual-fuel diesel engine

  1. A direct plasma injection system into an RFQ for clean and safe ion implantation

    International Nuclear Information System (INIS)

    Takeuchi, T.; Katayama, T.; Okamura, M.; Yano, K.; Sakumi, A.; Hattori, T.; Hayashizaki, N.; Jameson, R.A.

    2002-01-01

    A new injection system, direct plasma injection system, was tested and its principle was proved successfully. We found that one of advantages of this injection system was efficient consumption of source materials. Large portions of induced ions can be injected into a first stage accelerator. This feature is quite useful for ion implantation applications, because toxic exhaust gas can be eliminated. In order to utilize this system for industrial application, the feasibility of a boron injection scheme using a Nd:YAG laser system was investigated

  2. Contribution to the study of an lpg jet in the combustion chamber of a spark-ignition engine; Contribution a l'etude d'un jet de gpl dans la chambre de combustion d'un moteur a allumage commande, pour differentes strategies d'injection

    Energy Technology Data Exchange (ETDEWEB)

    Duong Viet, D.

    2002-07-01

    It appears tempting to combine the less polluting combustion of LPG with the energy performances of a direct injection spark-ignition engine. To this aim the study of high pressure injection of a liquid LPG jet, directly inside the combustion chamber of an engine was performed in two ways: Experimental studies: one with fast cinematography and another with the method of Doppler phases in an one-cylinder 'transparent' engine for various conditions of injection and without combustion. They respectively deliver empirical laws for the jet development and some informations about size and speed of the droplets of LPG. A modeling of the jet could then be made on the basis of a turbulent and deviated jet the parameters of which could be adjusted using results of the preceding experimental study. (author)

  3. A Theoretical and Experimental Analysis of Post-Compression Water Injection in a Rolls-Royce M250 Gas Turbine Engine

    Science.gov (United States)

    2015-05-18

    ROLLS-ROYCE M250 GAS TURBINE ENGINE by Midshipman 1/C Brian R. He United States Naval Academy Annapolis, Maryland...Injection in a Rolls- Royce M250 Gas Turbine Engine 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) He...output, efficiency, operating conditions, and emissions of injecting water at the compressor discharge of a Rolls-Royce M250 . The results

  4. Effects of pilot injection pressure on the combustion and emissions characteristics in a diesel engine using biodiesel–CNG dual fuel

    International Nuclear Information System (INIS)

    Ryu, Kyunghyun

    2013-01-01

    Highlights: • Injection pressure of pilot fuel in dual fuel combustion (DFC) affects the engine power and exhaust emissions. • In the biodiesel–CNG DFC mode, the combustion begins and ends earlier as the pilot-fuel injection pressure increases. • The ignition delay in the DFC mode is about 1.2–2.6 °CA longer than that in the diesel single fuel combustion (SFC) mode. • The smoke and NOx emissions are significantly reduced in the DFC mode. - Abstract: Biodiesel–compressed natural gas (CNG) dual fuel combustion (DFC) system is studied for the simultaneous reduction of particulate matters (PM) and nitrogen oxides (NOx) from diesel engine. In this study, biodiesel is used as a pilot injection fuel to ignite the main fuel, CNG of DFC system. In particular, the pilot injection pressure is controlled to investigate the characteristics of engine performance and exhaust emissions in a single cylinder diesel engine. The results show that the indicated mean effective pressure (IMEP) of biodiesel–CNG DFC mode is lower than that of diesel single fuel combustion (SFC) mode at higher injection pressure. However, the combustion stability of biodiesel–CNG DFC mode is increased with the increase of pilot injection pressure. At the same injection pressure, the start of combustion of biodiesel–CNG DFC is delayed compared to diesel SFC due to the increase of ignition delay of pilot fuel. On the contrary, it is observed that as the pilot injection pressure increase, the combustion process begins and ends a little earlier for biodiesel–CNG DFC. The ignition delay in the DFC is about 1.2–2.6 °CA longer compared to diesel SFC, but decreases with increases of pilot injection pressure. Smoke and NOx emissions are decreased and increased, respectively, as the pilot injection pressure increases in the biodiesel–CNG DFC. In comparison to diesel SFC, smoke emissions are significantly reduced over all the operating conditions and NOx emissions also exhibited similar

  5. Study of hydrocarbon emission in small direct injection engines; Kogata DI diesel kikan ni okeru teifukaji HC haishutsu ni kansuru kiso kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Tsurushima, T; Zhang, L; Ueda, T; Fujino, R; Yokota, K [Isuzu Advanced Engineering Center, Tokyo (Japan)

    1997-10-01

    The cause of unburned hydrocarbon emission in small DI diesel engines at light load was studied. An optically accessible engine which was enabled to visualize the squish area was used to investigate the behavior of spray, mixture distribution and so on. Based on these observations and engine tests, the factors such as the direct impingement of liquid phase fuel spray to the combustion chamber wall the unevenness of fuel spray among holes and spreading of the fuel droplets, mixture and flame to the squish area were supposed to be the cause of forming HC emission. 18 refs., 10 figs., 2 tabs.

  6. Critical firing and misfiring boundary in a spark ignition methanol engine during cold start based on single cycle fuel injection

    International Nuclear Information System (INIS)

    Li, Zhaohui; Gong, Changming; Qu, Xiang; Liu, Fenghua; Sun, Jingzhen; Wang, Kang; Li, Yufeng

    2015-01-01

    The influence of the mass of methanol injected per cycle, ambient temperature, injection and ignition timing, preheating methods, and supplying additional liquefied petroleum gas (LPG) injection into the intake manifold on the critical firing and misfiring boundary of an electronically injection controlled spark ignition (SI) methanol engine during cold start were investigated experimentally based on a single cycle fuel injection with cycle-by-cycle control strategy. The critical firing and misfiring boundary was restricted by all parameters. For ambient temperatures below 16 °C, methanol engines must use auxiliary start-aids during cold start. Optimal control of the methanol injection and ignition timing can realize ideal next cycle firing combustion after injection. Resistance wire and glow plug preheating can provide critical firing down to ambient temperatures of 5 °C and 0 °C, respectively. Using an additional LPG injection into the intake manifold can provide critical firing down to an ambient temperature of −13 °C during cold start. As the ambient temperature decreases, the optimal angle difference between methanol injection timing and LPG injection timing for critical firing of a methanol engine increases rapidly during cold start. - Highlights: • A single cycle fuel injection and cycle-by-cycle control strategy are used to study. • In-cylinder pressure and instantaneous speed were used to determine firing boundary. • For the ambient temperatures below 16 °C, an auxiliary start-aids must be used. • A preheating and additional LPG were used to expand critical firing boundary. • Additional LPG can result in critical firing down to ambient temperature of −13 °C

  7. Photoelectric schlieren method used to study the properties of diesel engine injection systems

    International Nuclear Information System (INIS)

    Reznicek, R.

    1987-01-01

    The time dependence of the fuel flow rate issuing from the injector nozzle represents very important information concerning the properties of Diesel engine injection systems. By analysing the delivery rate, it is possible to judge a new design, and the modifications and adjustments of Diesel engine injection systems. A number of devices for measuring the delivery rate, frequently founded on mechanical principles, have also been constructed. Mechanical methods are laborious, require complicated measuring instruments, and the analysis of the results is quite tedious. For investigating the delivery rate, one can also use the intensity of the luminous flux of the light ray which is intersected, and consequently its intensity decreased, by the flow of the delivered fuel. The schlieren method can be used for this purpose, employing a thin beam of parallel light rays and a photoelectric sensor placed immediately beyond the cut-off slit. After adjustment and calibration, the variations of the original electric signal represent the time variation of the delivery rate by the nozzle

  8. Installation, maintenance and operating manual for the Lucas-type fuel injection system of the 3 B rotary engine

    Science.gov (United States)

    1985-01-01

    The installation procedure, maintenance, adjustment and operation of a Lucas type fuel injection system for 13B rotary racing engine is outlined. Components of the fuel injection system and installation procedure and notes are described. Maintenance, adjustment, and operation are discussed.

  9. Effect of glycerol ethoxylate as an ignition improver on injection and combustion characteristics of hydrous ethanol under CI engine condition

    International Nuclear Information System (INIS)

    Munsin, R.; Laoonual, Y.; Jugjai, S.; Matsuki, M.; Kosaka, H.

    2015-01-01

    Highlights: • Glycerol ethoxylate (GE) shows the similar results as the commercial additive. • GE decreases injection rate, but increases injection delay and duration of ethanol. • GE shortens ignition delay and decreases heat released in premixed burn of ethanol. • GE has a minor effect on flame temperature of ethanol. • KL factor and soot of ethanol are sensitive to both GE and the commercial additive. - Abstract: This paper investigates the effects of glycerol ethoxylate as an ignition improver on injection and combustion characteristics of hydrous ethanol under a CI engine condition. Injection characteristics were investigated by an in-house injection rate measurement device based on the Zeuch method, while spray combustion has been performed in the rapid compression and expansion machine (RCEM). The CI engine condition indicated as density, pressure and temperature of compressed synthetic gas, consisting of 80% argon and 20% oxygen, at fuel injection timing in RCEM of 21 kg/m 3 , 4.4 MPa and 900 K, respectively. This condition is equivalent to the isentropic compression of air of the actual CI engine with compression ratio of 22. Hydrous ethanol without ignition improver (Eh95) and the ethanol dedicated for heavy duty vehicles (ED95: composed of hydrous ethanol with the commercial additive for ED95) are reference fuels representing low and high quality ethanol fuel for CI engines, respectively. All test fuels are injected at constant heat input. The results indicate that the additional ignition improvers change injection characteristics, i.e. injection delay, injection rate and discharge coefficient of hydrous ethanol. The maximum injection rates at fully opened needle for the ethanol dedicated for heavy duty vehicles (ED95) and hydrous ethanol with 5% glycerol ethoxylate (5%GE) are lower than that of hydrous ethanol without ignition improver (Eh95) by approximately 10%. Additional injection duration is required for ED95 and 5%GE to maintain a

  10. An investigation of the effects of spray angle and injection strategy on dimethyl ether (DME) combustion and exhaust emission characteristics in a common-rail diesel engine

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Seung Hyun; Cha, June Pyo [Graduate School of Hanyang University, Hanyang University, 17 Haengdang-dong, Sungdong-gu, Seoul, 133-791 (Korea); Lee, Chang Sik [Department of Mechanical Engineering, Hanyang University, 17 Haengdang-dong, Sungdong-gu, Seoul 133-791 (Korea)

    2010-11-15

    An experimental investigation was performed on the effects of spray angle and injection strategies (single and multiple) on the combustion characteristics, concentrations of exhaust emissions, and the particle size distribution in a direct-injection (DI) compression ignition engine fueled with dimethyl ether (DME) fuel. In this study, two types of narrow spray angle injectors ({theta}{sub spray} = 70 and 60 ) were examined and its results were compared with the results of conventional spray angle ({theta}{sub spray} = 156 ). In addition, to investigate the optimal operating conditions, early single-injection and multiple-injection strategies were employed to reduce cylinder wall-wetting of the injected fuels and to promote the ignition of premixed charge. The engine test was performed at 1400 rpm, and the injection timings were varied from TDC to BTDC 40 of the crank angle. The experimental results showed that the combustion pressure from single combustion for narrow-angle injectors ({theta}{sub spray} = 70 and 60 ) is increased, as compared to the results of the wide-angle injector ({theta}{sub spray} = 156 ) with advanced injection timing of BTDC 35 . In addition, two peaks of the rate of heat release (ROHR) are generated by the combustion of air-fuel premixed mixtures. DME combustion for all test injectors indicated low levels of soot emissions at all injection timings. The NO{sub x} emissions for narrow-angle injectors simultaneously increased in proportion to the advance in injection timing up to BTDC 25 , whereas BTDC 20 for the wide-angle injector. For multiple injections, the combustion pressure and ROHR of the first injection with narrow-angle injectors are combusted more actively, and the ignition delay of the second injected fuel is shorter than with the wide-angle injector. However, the second combustion pressure and ROHR were lower than during the first injection, and combustion durations are prolonged, as compared to the wide-angle injector. With

  11. An investigation of the effects of spray angle and injection strategy on dimethyl ether (DME) combustion and exhaust emission characteristics in a common-rail diesel engine

    International Nuclear Information System (INIS)

    Yoon, Seung Hyun; Cha, June Pyo; Lee, Chang Sik

    2010-01-01

    An experimental investigation was performed on the effects of spray angle and injection strategies (single and multiple) on the combustion characteristics, concentrations of exhaust emissions, and the particle size distribution in a direct-injection (DI) compression ignition engine fueled with dimethyl ether (DME) fuel. In this study, two types of narrow spray angle injectors (θ spray = 70 and 60 ) were examined and its results were compared with the results of conventional spray angle (θ spray = 156 ). In addition, to investigate the optimal operating conditions, early single-injection and multiple-injection strategies were employed to reduce cylinder wall-wetting of the injected fuels and to promote the ignition of premixed charge. The engine test was performed at 1400 rpm, and the injection timings were varied from TDC to BTDC 40 of the crank angle. The experimental results showed that the combustion pressure from single combustion for narrow-angle injectors (θ spray = 70 and 60 ) is increased, as compared to the results of the wide-angle injector (θ spray = 156 ) with advanced injection timing of BTDC 35 . In addition, two peaks of the rate of heat release (ROHR) are generated by the combustion of air-fuel premixed mixtures. DME combustion for all test injectors indicated low levels of soot emissions at all injection timings. The NO x emissions for narrow-angle injectors simultaneously increased in proportion to the advance in injection timing up to BTDC 25 , whereas BTDC 20 for the wide-angle injector. For multiple injections, the combustion pressure and ROHR of the first injection with narrow-angle injectors are combusted more actively, and the ignition delay of the second injected fuel is shorter than with the wide-angle injector. However, the second combustion pressure and ROHR were lower than during the first injection, and combustion durations are prolonged, as compared to the wide-angle injector. With advanced timing of the first injection, narrow

  12. Investigation of Diesel combustion using multiple injection strategies for idling after cold start of passenger-car engines

    Energy Technology Data Exchange (ETDEWEB)

    Payri, F.; Broatch, A.; Salavert, J.M.; Martin, J. [CMT-Motores Termicos, Universidad Politecnica de Valencia, Aptdo. 22012, E-46071 Valencia (Spain)

    2010-10-15

    A comprehensive investigation was carried out in order to better understand the combustion behaviour in a low compression ratio DI Diesel engine when multiple injection strategies are applied just after the engine cold starts in low temperature conditions (idling). More specifically, the aim of this study was twofold: on one hand, to understand the effect of the multiple injection strategies on the indicated mean effective pressure; on the other hand, to contribute to the understanding of combustion stability characterized by the coefficient of variation of indicated mean effective pressure. The first objective was fulfilled by analyzing the rate of heat release obtained by in-cylinder pressure diagnosis. The results showed that the timing of the pilot injection closest to the main injection was the most influential parameter based on the behaviour of the rate of heat release (regardless of the multiple injection strategy applied). For the second objective, the combustion stability was found to be correlated with the combustion centroid angle. The results showed a trend between them and the existence of a range of centroid angles where the combustion stability is strong enough. In addition, it was also evident that convenient split injection allows shifting the centroid to such a zone and improves combustion stability after start. (author)

  13. Lubrication and wear in diesel engine injection equipment fuelled by dimethyl ether (DME)

    DEFF Research Database (Denmark)

    Sivebæk, Ion Marius

    2003-01-01

    Dimethyl ether (DME) has been recognised as an excellent fuel for diesel engines for over one decade now. DME fueled engines emit virtually no particulate matter even at low NOx levels. DME has thereby the potential of reducing the diesel engine emissions without filters or other devices...... that jeopardise the high efficiency of the engine and increase the manufacturing costs. DME has a low toxicity and can be made from anything containing carbon including biomass. If DME is produced from cheap natural gas from remote locations, the price of this new fuel could even become lower than that of diesel...... oil. Fueling diesel engines with DME presents two significant problems: The injection equipment can break down due to extensive wear and DME attacks nearly all known elastomers. The latter problem renders dynamic sealing diƣult whereas the first one involves the poor lubrication qualities of DME which...

  14. Power Balancing of Inline Multicylinder Diesel Engine

    Directory of Open Access Journals (Sweden)

    S. H. Gawande

    2012-01-01

    Full Text Available In this work, a simplified methodology is presented for power balancing by reducing the amplitude of engine speed variation, which result in excessive torsional vibrations of the crankshaft of inline six-cylinder diesel engine. In modern fuel injection systems for reciprocating engines, nonuniform cylinder-wise torque contribution is a common problem due to nonuniform fuel supply due to a defect in fuel injection system, causing increased torsional vibration levels of the crankshaft and stress of mechanical parts. In this paper, a mathematical model for the required fuel adjustment by using amplitude of engine speed variation applied on the flywheel based on engine dynamics is suggested. From the found empirical relations and FFT analysis, the amplitude of engine speed variation (i.e., torsional vibration levels of the crankshaft of inline six-cylinder diesel engine genset can be reduced up to 55%. This proposed methodology is simulated by developing MATALB code for uniform and nonuniform working of direct injection diesel engine of SL90 type manufactured by Kirloskar Oil Engine Ltd., Pune, India.

  15. Research on Continuous Injection Direct Rolling Process for PMMA Optical Plate

    Directory of Open Access Journals (Sweden)

    HaiXiong Wang

    2014-06-01

    Full Text Available Continuous injection direct rolling (CIDR combined intermittent injection and rolling process is a new technology for molding optical polymer plates with microstructured patterns; research on forming PMMA optical plates is an aspect of it in this paper. The equipment of CIDR process consists of plastic injection module, precision rolling module, and automatic coiling module. Based on the establishing mathematical CIDR models, numerical analysis was used to explode the distribution of velocity, temperature, and pressure in injection-rolling zone. The simulation results show that it is feasible to control the temperature, velocity, and injection-rolling force, so it can form polymer plate under certain process condition. CIDR experiment equipment has been designed and produced. PMMA optical plate was obtained by CIDR experiments, longitudinal thickness difference is 0.005 mm/200 mm, horizontal thickness difference is 0.02/200 mm, transmittance is 86.3%, Haze is 0.61%, and the difference is little compared with optical glasses. So it can be confirmed that CIDR process is practical to produce PMMA optical plates.

  16. Reducing Diesel Engine Emission Using Reactivity Controlled Approach

    Directory of Open Access Journals (Sweden)

    Osama Hasib Ghazal

    2018-01-01

    Full Text Available Several automobile manufacturers are interested in investigating of dual fuel internal combustion engines, due to high efficiencand low emissions. Many alternative fuels have been used in dual fuel mode for IC engine, such as methane, hydrogen, and natural gas. In the present study, a reactivity controlled compression ignition (RCCI engine using gasoline/diesel (G/D dual fuel has been investigated. The effectof mixing gasoline with diesel fuel on combustion characteristic, engine performance and emissions has been studied. The gasoline was injected in the engine intake port, to produce a homogeneous mixture with air. The diesel fuel was injected directly to the combustion chamber during compression stroke to initiate the combustion process. A direct injection compression ignition engine has been built and simulated using ANSYS Forte professional code. The gasoline amount in the simulation varied from (50%-80% by volume. The diesel fuel was injected to the cylinder in two stages. The model has been validated and calibrated for neat diesel fuel using available data from the literature. The results show that the heat release rate and the cylinder pressure increased when the amount of added gasoline is between 50%-60% volume of the total injected fuels, compared to the neat diesel fuel. Further addition of gasoline will have a contrary effect. In addition, the combustion duration is extended drastically when the gasoline ratio is higher than 60% which results in an incomplete combustion. The NO emission decreased drastically as the gasoline ratio increased. Moreover, addition of gasoline to the mixture increased the engine power, thermal efficienc and combustion efficienc compared to neat diesel fuel.

  17. Vehicle driving cycle performance of the spark-less di-ji hydrogen engine

    Energy Technology Data Exchange (ETDEWEB)

    Boretti, Alberto A. [School of Science and Engineering, University of Ballarat, PO Box663, Ballarat, VIC 3353 (Australia)

    2010-05-15

    The paper describes coupled CFD combustion simulations and CAE engine performance computations to describe the operation over the full range of load and speed of an always lean burn, Direct Injection Jet Ignition (DI-JI) hydrogen engine. Jet ignition pre-chambers and direct injection are enablers of high efficiencies and load control by quantity of fuel injected. Towards the end of the compression stroke, a small quantity of hydrogen is injected within the spark-less pre-chamber of the DI-JI engine, where it mixes with the air entering from the main chamber and auto-ignites because of the high temperature of the hot glow plug. Then, jets of partially combusted hot gases enter the main chamber igniting there in the bulk, over multiple ignition points, lean stratified mixtures of air and fuel. Engine maps of brake specific fuel consumption vs. speed and brake mean effective pressure are computed first. CAE vehicle simulations are finally performed evaluating the fuel consumption over emission cycles of a vehicle equipped with this engine. (author)

  18. Imaging diagnostics of ethanol port fuel injection sprays for automobile engine applications

    International Nuclear Information System (INIS)

    Padala, Srinivas; Le, Minh Khoi; Kook, Sanghoon; Hawkes, Evatt R.

    2013-01-01

    This paper presents characteristics of ethanol sprays at port fuel injection (PFI) conditions with variations in injection and ambient parameters. Details of temporal and spatial development of ethanol PFI sprays are studied using Mie-scattering and high-speed shadowgraph imaging techniques. Momentum flux-based injection rate measurement is also performed. The influences of fuel flow-rate, injection duration, and ambient air cross-flow are of particular interest in an effort to understand ethanol PFI spray characteristics that are relevant to automobile engines. For comparison purposes, the results from gasoline fuel are also presented. Ethanol flow-rate effects are studied using two injectors with different nozzle-hole sizes at a fixed injection pressure. From the experiments, it was found that the actual injection duration was longer for the higher flow-rate injector although an electronic pulse width was fixed. This was due to an extended delay in the injector needle closing as the flow resistance against the needle was increased for the high flow-rate injector. For liquid droplets, the larger hole size of the higher flow-rate injector caused a higher mean droplet diameter and higher number of droplets. Injection duration was also varied to study transient spray behaviour: short-injection sprays with the end-of-injection transient dominating the overall spray development were compared to long, steady-injection sprays. From Mie-scattering images, the number of droplets and mean droplet diameter were found to be less for the short injection sprays. Detailed analysis using an axial profile of the number of droplets and mean droplet diameter suggested that the observed trends were a result of increased evaporation rate near the nozzle after the end of injection. This was consistent with shadowgraph images showing no liquid regions but only the vapour-phase fuel near the nozzle. Under the influence of ambient air cross-flow, both mean droplet diameter and number of

  19. Comparison of long-term voice outcomes after vocal fold augmentation using autologous fat injection by direct microlaryngoscopy versus office-based calcium hydroxylapatite injection.

    Science.gov (United States)

    Zeleník, Karol; Walderová, Radana; Kučová, Hana; Jančatová, Debora; Komínek, Pavel

    2017-08-01

    The objective is to compare the long-term voice outcomes of vocal fold augmentation (VFA) using autologous fat injection via direct microlaryngoscopy versus office-based calcium hydroxylapatite (CaHA) injection. Patients with glottal insufficiency and a gap no greater than 3 mm caused by unilateral vocal fold paralysis or vocal fold atrophy were prospectively recruited to the study from September 2012 to September 2015. From September 2012 to May 2014, VFA was only performed using autologous fat via direct microlaryngoscopy under general anesthesia (N = 14). From May 2014 to September 2015, VFA was performed as an office-based procedure using a transoral approach to inject CaHA (N = 17). Videolaryngostroboscopic evaluation, subjective satisfaction with voice, voice handicap index (VHI), and maximal phonation time (MPT) were analyzed pre-injection and 12 months after VFA. A total of 31 patients were analyzed. One year after VFA, 67.8% of the patients were satisfied with their voice, with no significant difference between groups (P = 0.247). The mean improvement in VHI in the autologous fat group was 31.6 ± 16.82 versus 35 ± 27.24 in the CaHA group (P = 0.664). MPT improvement was also similar in the two groups: 5.5 ± 2.52 for the autologous fat group versus 6.0 ± 3.98 for the CaHA group (P = 0.823). Both autologous fat injection via direct microlaryngoscopy and office-based CaHA injection have good long-term results. There were no differences in the treatment results of the two procedures 1 year after injection.

  20. Analysis of emergency core cooling capability of direct vessel vertical injection using CFX

    International Nuclear Information System (INIS)

    Yoon, Sang H.; Yu, Yong H.; Suh, Kune Y.

    2003-01-01

    More reliable and efficient safety injection system is of utmost importance in the design of advanced reactors such as the APR1400 (Advanced Power Reactor 1400 MWe). In this work, a new idea is proposed to inject the Emergency Core Cooling (ECC) water utilizing a dedicated nozzle with a vertically downward elbow. The Direct Vessel Injection (DVI) system is located horizontally above the cold leg in the APR1400. However, the horizontal injection method may not always satisfy the ECC penetration requirement into the core on account of rather involved multidimensional thermal and hydraulic phenomena occurring in the annular reactor downcomer such as bypass, impingement, entrainment and sweepout, condensation oscillation, etc. Thus, a novel concept is called for from the reactor safety point of view. The Direct Vessel Vertical Injection (DVVI) system is one of these efforts to penetrate as much the ECC water through the downcomer into the core as is practically achievable. The DVVI system can increase the momentum of the downward flow, thus minimizing the effect of water impingement on the core barrel and the direct bypass though the break. To support the claim of increased downward momentum of flow in the DVVI system, computational fluid dynamics analyses were performed using CFX. The new concept of the DVVI system, which can certainly help increase the core thermal margin, is found to be more efficient than DVI. If the structural problem in the manufacturing process is properly solved, this concept can safely be applied in the advanced nuclear reactor design

  1. Multifuel rotary aircraft engine

    Science.gov (United States)

    Jones, C.; Berkowitz, M.

    1980-01-01

    The broad objectives of this paper are the following: (1) to summarize the Curtiss-Wright design, development and field testing background in the area of rotary aircraft engines; (2) to briefly summarize past activity and update development work in the area of stratified charge rotary combustion engines; and (3) to discuss the development of a high-performance direct injected unthrottled stratified charge rotary combustion aircraft engine. Efficiency improvements through turbocharging are also discussed.

  2. Injectable dextran hydrogels fabricated by metal-free click chemistry for cartilage tissue engineering.

    Science.gov (United States)

    Wang, Xiaoyu; Li, Zihan; Shi, Ting; Zhao, Peng; An, Kangkang; Lin, Chao; Liu, Hongwei

    2017-04-01

    Injectable dextran-based hydrogels were prepared for the first time by bioorthogonal click chemistry for cartilage tissue engineering. Click-crosslinked injectable hydrogels based on cyto-compatible dextran (Mw=10kDa) were successfully fabricated under physiological conditions by metal-free alkyne-azide cycloaddition (click) reaction between azadibenzocyclooctyne-modified dextran (Dex-ADIBO) and azide-modified dextran (Dex-N 3 ). Gelation time of these dextran hydrogels could be regulated in the range of approximately 1.1 to 10.2min, depending on the polymer concentrations (5% or 10%) and ADIBO substitution degree (DS, 5 or 10) of Dex-ADIBO. Rheological analysis indicated that the dextran hydrogels were elastic and had storage moduli from 2.1 to 6.0kPa with increasing DS of ADIBO from 5 to 10. The in vitro tests revealed that the dextran hydrogel crosslinked from Dex-ADIBO DS 10 and Dex-N 3 DS 10 at a polymer concentration of 10% could support high viability of individual rabbit chondrocytes and the chondrocyte spheroids encapsulated in the hydrogel over 21days. Individual chondrocytes and chondrocyte spheroids in the hydrogel could produce cartilage matrices such as collagen and glycosaminoglycans. However, the chondrocyte spheroids produced a higher content of matrices than individual chondrocytes. This study indicates that metal-free click chemistry is effective to produce injectable dextran hydrogels for cartilage tissue engineering. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. A study on the amount of pilot injection and its effects on rich and lean boundaries of the premixed CNG/air mixture for a CNG/diesel dual-fuel engine

    Energy Technology Data Exchange (ETDEWEB)

    Zhiqiang Lin; Wanhua Su [Tianjin University (China). State Key Laboratory of Engines

    2003-07-01

    A sequential port injection, lean-burn, fully electronically-controlled compressed natural gas (CNG)/diesel dual-fuel engine has been developed based on a turbo-charged and inter-cooled direct injection (D.I.) diesel engine. During the optimisation of engine overall performance, the effects of pilot diesel and premixed CNG/air mixture equivalence ratio on emissions (CO, HC, NO{sub x}, soot), knocking, misfire and fuel economy are studied. The rich and lean boundaries of the premixed CNG/air mixture versus engine load are also provided, considering the acceptable values of NO{sub x} and THC emissions, respectively. It is interesting to find that there is a critical amount of pilot diesel for each load and speed point, which proved to be the optimum amount of pilot fuel. Any decrease in the amount of pilot diesel from this optimum amount results in an increase of NO{sub x} emissions, because the premixed CNG/air mixture must be made richer, otherwise THC emissions would increase. However, the soot emissions remain almost unchanged at a very low level. (author)

  4. 78 FR 47534 - Airworthiness Directives; General Electric Company Turbofan Engines

    Science.gov (United States)

    2013-08-06

    ... Airworthiness Directives; General Electric Company Turbofan Engines AGENCY: Federal Aviation Administration (FAA... directive (AD) 2013-14-51 for General Electric Company (GE) GE90-110B1 and GE90-115B turbofan engines with... all known U.S. owners and operators of GE90-110B1 and GE90-115B turbofan engines. AD 2013-14-51...

  5. Uncooled EGR as a means of limiting wall-wetting under early direct injection conditions

    NARCIS (Netherlands)

    Boot, M.D.; Luijten, C.C.M.; Somers, L.M.T.; Eguz, U.; Erp, D.D.T.M. van; Albrecht, A.; Baert, R.S.G.

    2009-01-01

    Collision of injected fuel spray against the cylinder liner (wall-wetting) is one of the main hurdles that must be overcome in order for early direct injection Premixed Charge Compression Ignition (EDI PCCI) combustion to become a viable alternative for conventional DI diesel combustion. Preferably,

  6. Fuel supply system for diesel engines. Kraftstoffzufuhrsystem fuer Dieselmotoren

    Energy Technology Data Exchange (ETDEWEB)

    Mowbray, D F; Jarrett, B A

    1979-10-05

    The invention deals with a fuel feeding system, in particular for diesel engines with direct injection, provided with electromagnetic fuel pumps and injection nozzles for every combustion chamber. The pumps are equiped with control systems, which are actuated during the injection process. Switch valves with magnetic control devices serve as controllers.

  7. Numerical investigation of the effect of injection strategy on mixture formation and combustion process in a port injection natural gas rotary engine

    International Nuclear Information System (INIS)

    Fan, Baowei; Pan, Jianfeng; Yang, Wenming; Liu, Yangxian; Bani, Stephen; Chen, Wei

    2017-01-01

    Highlights: • For injection timing, the fuel movement is controlled by the intensity of the vortex I. • For injection duration, the fuel movement is controlled by the value of jet flux. • The ideal fuel distribution at ignition timing for high combustion rate is studied. • The optimal injection strategy had an increase in the peak pressure and NO emissions. - Abstract: This work aimed to numerically study the influence of injection strategy on mixture formation and combustion process in a port injection natural gas rotary engine. On the base of a 3D dynamic simulation model which was established in our previous work, some critical information was obtained, which was difficult to obtain through experiment, in terms of the flow field, the fuel distribution, the temperature field and the concentration fields of some intermediates. Simulation results showed that for mixture formation, the movements of fuel in injection stage were mainly controlled by the intensity of the vortex I for injection timing, and the value of jet flux for injection duration respectively. With retarded injection timing, the decreasing intensity of the vortex I resulted in less fuel moving toward the back of the combustion chamber. With the extension in injection duration, the decreasing value of jet flux resulted in more fuel staying at the back of the combustion chamber. For combustion process, the overall combustion rate for injection strategy which had an injection timing of 390 °CA (BTDC) and injection duration of 51.5 °CA (case ID4) was the fastest. This was mainly due to the fact that the accumulation area of fuel was at the middle and front of the combustion chamber. Meanwhile, fuel concentration near the leading and trailing spark plugs was conducive for the flame kernel formation. Compared with the injection strategy which had an injection timing of 450 °CA (BTDC) and an injection duration of 55 °CA (case IT1), the improved combustion rate of case ID4 had a 23% increase in

  8. Common rail fuel injection system for improvement of engine performance and reduction of exhaust emission on heavy duty diesel engine; Common rail system ni yoru seino haishutsu gas no kaizen

    Energy Technology Data Exchange (ETDEWEB)

    Kato, T; Koyama, T; Sasaki, K; Mori, K; Mori, K [Mitsubishi Motor Corp., Tokyo (Japan)

    1997-10-01

    With the objective of improvement of engine performance and reduction of exhaust emissions, influence of control method to decrease initial injection rate and effect of injector types on fuel leakage of common rail fuel injection system (Common Rail System) were investigated. As a results, it became clear that injector with 2-way valve brings improvement of engine performance and reduction of exhaust emissions as compared with injector with 3-way valve because injector with 2-way valve has lower fuel leakage and is able to use higher injection pressure than injector with 3-way valve. 5 refs., 13 figs., 1 tab.

  9. Effects of fresh lubricant oils on particle emissions emitted by a modern gasoline direct injection passenger car.

    Science.gov (United States)

    Pirjola, Liisa; Karjalainen, Panu; Heikkilä, Juha; Saari, Sampo; Tzamkiozis, Theodoros; Ntziachristos, Leonidas; Kulmala, Kari; Keskinen, Jorma; Rönkkö, Topi

    2015-03-17

    Particle emissions from a modern turbocharged gasoline direct injection passenger car equipped with a three-way catalyst and an exhaust gas recirculation system were studied while the vehicle was running on low-sulfur gasoline and, consecutively, with five different lubrication oils. Exhaust particle number concentration, size distribution, and volatility were determined both at laboratory and on-road conditions. The results indicated that the choice of lubricant affected particle emissions both during the cold start and warm driving cycles. However, the contribution of engine oil depended on driving conditions being higher during acceleration and steady state driving than during deceleration. The highest emission factors were found with two oils that had the highest metal content. The results indicate that a 10% decrease in the Zn content of engine oils is linked with an 11-13% decrease to the nonvolatile particle number emissions in steady driving conditions and a 5% decrease over the New European Driving Cycle. The effect of lubricant on volatile particles was even higher, on the order of 20%.

  10. Impact of physical properties of mixture of diesel and biodiesel fuels on hydrodynamic characteristics of fuel injection system

    Directory of Open Access Journals (Sweden)

    Filipović Ivan M.

    2014-01-01

    Full Text Available One of the alternative fuels, originating from renewable sources, is biodiesel fuel, which is introduced in diesel engines without major construction modifications on the engine. Biodiesel fuel, by its physical and chemical properties, is different from diesel fuel. Therefore, it is expected that by the application of a biodiesel fuel, the characteristic parameters of the injection system will change. These parameters have a direct impact on the process of fuel dispersion into the engine cylinder, and mixing with the air, which results in an impact on the quality of the combustion process. Method of preparation of the air-fuel mixture and the quality of the combustion process directly affect the efficiency of the engine and the level of pollutant emissions in the exhaust gas, which today is the most important criterion for assessing the quality of the engine. The paper presents a detailed analysis of the influence of physical properties of a mixture of diesel and biodiesel fuels on the output characteristics of the fuel injection system. The following parameters are shown: injection pressure, injection rate, the beginning and duration of injection, transformation of potential into kinetic energy of fuel and increase of energy losses in fuel injection system of various mixtures of diesel and biodiesel fuels. For the analysis of the results a self-developed computer program was used to simulate the injection process in the system. Computational results are verified using the experiment, for a few mixtures of diesel and biodiesel fuels. This paper presents the verification results for diesel fuel and biodiesel fuel in particular.

  11. Direct injection of {sup 188}Re-microspheres in the treatment of hepatocellular carcinoma. Compared with traditional percutaneous ethanol injection: an animal study

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Y.C.; Lee, J.C.; Huang, Y.S. [Dept. of Veterinary Medicine, National Chung-Hsing Univ., Taichung (Taiwan); Dept. of Nuclear Medicine (Taiwan); Tsai, S.C. [Show Chwan Memorial Hospital (Taiwan); Hung, G.U. [Changhua Christian Hospital, Changhua (Taiwan); Lin, W.Y. [Taichung Veterans General Hospital, Taichung (Taiwan)

    2005-07-01

    The aim of this study was to compare the therapeutic efficacies of direct intratumoural injection of {sup 188}Re microspheres (DIRM) and direct intratumoural injection of ethanol (DIE) in rabbits bearing liver tumours. Materials and methods: Fifteen rabbits bearing liver tumours were divided into three groups: group 1 received DIE, group 2 received DIRM, and group 3 (control) received saline. Tumour size was measured by liver sonography before injection, as well as 2, 4, 8, and 12 weeks after injection. Survival time was calculated from the day of treatment to three months after treatment by Kaplan-Meier survival analysis. Results: The mean survival time was 68{+-}9.8 days for the rabbits in the DIRM group, 55.8{+-}11.8 days for the DIE group, and 38.8{+-}6.2 days for the control group. Conclusion: The rabbits survived longer in the DIRM group than in the DIE group although there is no statistical significance. We believe the DIRM method has a good potential to be an alternative to DIE for the treatment of liver tumours. (orig.)

  12. Effects of Mixture Stratification on Combustion and Emissions of Boosted Controlled Auto-Ignition Engines

    Directory of Open Access Journals (Sweden)

    Jacek Hunicz

    2017-12-01

    Full Text Available The stratification of in-cylinder mixtures appears to be an effective method for managing the combustion process in controlled auto-ignition (CAI engines. Stratification can be achieved and controlled using various injection strategies such as split fuel injection and the introduction of a portion of fuel directly before the start of combustion. This study investigates the effect of injection timing and the amount of fuel injected for stratification on the combustion and emissions in CAI engine. The experimental research was performed on a single cylinder engine with direct gasoline injection. CAI combustion was achieved using negative valve overlap and exhaust gas trapping. The experiments were performed at constant engine fueling. Intake boost was applied to control the excess air ratio. The results show that the application of the late injection strategy has a significant effect on the heat release process. In general, the later the injection is and the more fuel is injected for stratification, the earlier the auto-ignition occurs. However, the experimental findings reveal that the effect of stratification on combustion duration is much more complex. Changes in combustion are reflected in NOX emissions. The attainable level of stratification is limited by the excessive emission of unburned hydrocarbons, CO and soot.

  13. Linear engine development for series hybrid electric vehicles

    Science.gov (United States)

    Toth-Nagy, Csaba

    This dissertation argues that diminishing oil reserves, concern over global climate change, and desire to improve ambient air quality all demand the development of environment-friendly personal transportation. In certain applications, series hybrid electric vehicles offer an attractive solution to reducing fuel consumption and emissions. Furthermore, linear engines are emerging as a powerplant suited to series HEV applications. In this dissertation, a linear engine/alternator was considered as the auxiliary power unit of a range extender series hybrid electric vehicle. A prototype linear engine/alternator was developed, constructed and tested at West Virginia University. The engine was a 2-stroke, 2-cylinder, dual piston, direct injection, diesel engine. Experiment on the engine was performed to study its behavior. The study variables included mass of the translator, amount of fuel injected, injection timing, load, and stroke with operating frequency and mechanical efficiency as the basis of comparison. The linear engine was analyzed in detail and a simple simulation model was constructed to compare the trends of simulation with the experimental data and to expand on the area where the experimental data were lacking. The simulation was based on a simple and analytical model, rather than a detailed and intensely numerical one. The experimental and theoretical data showed similar trends. Increasing translator mass decreased the operating frequency and increased compression ratio. Larger mass and increased compression ratio improved the ability of the engine to sustain operation and the engine was able to idle on less fuel injected into the cylinder. Increasing the stroke length caused the operating frequency to drop. Increasing fueling or decreasing the load resulted in increased operating frequency. This projects the possibility of using the operating frequency as an input for feedback control of the engine. Injection timing was varied to investigate two different

  14. An analysis of direct-injection spark-ignition (DISI) soot morphology

    Science.gov (United States)

    Barone, Teresa L.; Storey, John M. E.; Youngquist, Adam D.; Szybist, James P.

    2012-03-01

    We have characterized particle emissions produced by a 4-cylinder, 2.0 L DISI engine using transmission electron microscopy (TEM) and image analysis. Analyses of soot morphology provide insight to particle formation mechanisms and strategies for prevention. Particle emissions generated by two fueling strategies were investigated, early injection and injection modified for low particle number concentration emissions. A blend of 20% ethanol and 80% emissions certification gasoline was used for the study given the likelihood of increased ethanol content in widely available fuel. In total, about 200 particles and 3000 primary soot spherules were individually measured. For the fuel injection strategy which produced low particle number concentration emissions, we found a prevalence of single solid sub-25 nm particles and fractal-like aggregates. The modal diameter of single solid particles and aggregate primary particles was between 10 and 15 nm. Solid particles as small as 6 nm were present. Although nanoparticle aggregates had fractal-like morphology similar to diesel soot, the average primary particle diameter per aggregate had a much wider range that spanned from 7 to 60 nm. For the early fuel injection strategy, liquid droplets were prevalent, and the modal average primary particle diameter was between 20 and 25 nm. The presence of liquid droplets may have been the result of unburned fuel and/or lubricating oil originating from fuel impingement on the piston or cylinder wall; the larger modal aggregate primary particle diameter suggests greater fuel-rich zones in-cylinder than for the low particle number concentration point. However, both conditions produced aggregates with a wide range of primary particle diameters, which indicates heterogeneous fuel and air mixing.

  15. Construction engineering inspection direct cost survey.

    Science.gov (United States)

    2014-07-01

    The objective of the study was to provide a rationale to Georgia Department of Transportation : (GDOT) for Direct Costs in terms of salary and wages charged by qualified independent : contractors performing Construction Engineering Inspection (CEI) s...

  16. Detailed characterization of particulate matter emitted by lean-burn gasoline direct injection engine

    Energy Technology Data Exchange (ETDEWEB)

    Zelenyuk, Alla [Pacific Northwest National Laboratory, Richland, WA, USA; Wilson, Jacqueline [Pacific Northwest National Laboratory, Richland, WA, USA; Imre, Dan [Imre Consulting, Richland, WA, USA; Stewart, Mark [Pacific Northwest National Laboratory, Richland, WA, USA; Muntean, George [Pacific Northwest National Laboratory, Richland, WA, USA; Storey, John [Oak Ridge National Laboratory, Knoxville, TN, USA; Prikhodko, Vitaly [Oak Ridge National Laboratory, Knoxville, TN, USA; Lewis, Samuel [Oak Ridge National Laboratory, Knoxville, TN, USA; Eibl, Mary [Oak Ridge National Laboratory, Knoxville, TN, USA; Parks, Jim [Oak Ridge National Laboratory, Knoxville, TN, USA

    2016-11-10

    This study presents detailed characterization of the chemical and physical properties of PM emitted by a 2.0L BMW lean-burn turbocharged GDI engine operated under a number of combustion strategies that include lean homogeneous, lean stratified, stoichiometric, and fuel rich conditions. We characterized PM number concentrations, size distributions, and the size, mass, compositions, and effective density of fractal and compact individual exhaust particles. For the fractal particles, these measurements yielded fractal dimension, average diameter of primary spherules, and number of spherules, void fraction, and dynamic shape factors as function of particle size. Overall, the PM properties were shown to vary significantly with engine operation condition. Lean stratified operation yielded the most diesel-like size distribution and the largest PM number and mass concentrations, with nearly all particles being fractal agglomerates composed of elemental carbon with small amounts of ash and organics. In contrast, stoichiometric operation yielded a larger fraction of ash particles, especially at low speed and low load. Three distinct forms of ash particles were observed, with their fractions strongly dependent on engine operating conditions: sub-50 nm ash particles, abundant at low speed and low load, ash-containing fractal particles, and large compact ash particles that significantly contribute to PM mass loadings

  17. Effect of steam injection on nox emissions and performance of a single cylinder diesel engine fuelled with soy methyl ester

    Directory of Open Access Journals (Sweden)

    Manickam Madhavan V.

    2017-01-01

    Full Text Available Biodiesel attracts most of the researchers and automotive industries in recent years as an alternative fuel for diesel engines, because of its better lubricity property, higher cetane number, and less greenhouse gas emissions. The use of bio diesel leads to reduction in hydro carbons, carbon monoxide, and particulate matter, but increase in NOx emissions. Increase in biodiesel blends in standard diesel leads to increase in NOx emission. In this study, an attempt is made to reduce the NOx emis-sions of a diesel engine fueled with pure soy methyl ester (B100 with low pressure steam injection. Experiments were carried out and studied for both standard diesel and pure biodiesel of soy methyl ester with steam injection ratio of 5, 10, and 15% on mass ratio basis of air in the inlet manifold. The present study has shown that around 30% reduction in NOx can be achieved for the steam injection rate of 10% and considerable reduction for all other steam injection rates when compared to standard diesel and B100. It is also observed that steam injection having signifi-cant impact on reduction of other emissions such as HC, CO, and CO2. The study also noted marginal improvement in the engine brake power, brake thermal effi-ciency and reduction in specific fuel consumption at part loads and minor increase during peak load operation for the low pressure steam injection on B100.

  18. Study on effect of mixing mechanism by the transverse gaseous injection flow in scramjet engine with variable parameters

    Science.gov (United States)

    Yadav, Siddhita; Pandey, K. M.

    2018-04-01

    In scramjet engine the mixing mechanism of fuel and atmospheric air is very complicated, because the fuel have time in milliseconds for mixing with atmospheric air in combustion chamber having supersonic speed. Mixing efficiency of fuel and atmospheric air depends on mainly these parameters: Aspect ratio of injector, vibration amplitude, shock type, number of injector, jet to transverse flow momentum flux ratio, injector geometry, injection angle, molecular weight, incoming air stream angle, jet to transverse flow pressure ratio, spacing variation, mass flow rate of fuel etc. here is a very brief study of these parameters from previously done research on these parameters for the improvement of mixing efficiency. The mixing process have the significant role for the working of engine, and mixing between the atmospheric air and the jet fuel is significant factor for improving the overall thrust of the engine. The results obtained by study of papers are obtained by the 3D-Reynolds Average-Nervier-Stokes(RANS) equations along with the 2-equation k-ω shear-stress-transport (SST) turbulence model. Engine having multi air jets have 60% more mixing efficiency than single air jet, thus if the jets are increased, the mixing efficiency of engine can also be increased up to 150% by changing jet from 1 to 16. When using delta shape of injector the mixing efficiency is inversely proportional to the pressure ratio. When the fuel is injected inside the combustor from the top and bottom walls of the engine efficiency of mixing in reacting zone is higher than the single wall injection and in comparison to parallel flow, the transverse type flow is better as the atmospheric air jet can penetrate smoothly in the fuel jets and mixes well in less time. Hence this study of parameters and their effects on mixing can enhance the efficiency of mixing in engine.

  19. Experimental investigation of pistacia lentiscus biodiesel as a fuel for direct injection diesel engine

    International Nuclear Information System (INIS)

    Khiari, K.; Awad, S.; Loubar, K.; Tarabet, L.; Mahmoud, R.; Tazerout, M.

    2016-01-01

    Highlights: • Biodiesel is prepared from Pistacia Lentiscus oil. • Biodiesel yield is 94% when using 6:1 methanol/oil and 1% KOH catalyst at 50 °C. • BSFC and NOx emissions have increased with the use of biodiesel and its blends. • Biodiesel reduces significantly HC, CO and particulate emissions at high engine load. - Abstract: Biodiesel is currently seen as an interesting substitute for diesel fuel due to the continuing depletion of petroleum reserves and the environment pollution emerging from exhaust emissions. The present work is an experimental study conducted on a DI diesel engine running with either pistacia lentiscus (PL) biodiesel or its blends with conventional diesel fuel. PL biodiesel is obtained by converting PL seed oil via a single-step homogenous alkali catalyzed transesterification process. The PL biodiesel physicochemical properties, which are measured via standard methods, are similar to those of diesel fuel. A single cylinder, naturally aspirated DI diesel engine is operated at 1500 rpm with either PL biodiesel or its blends with diesel fuel for several ratios (50, 30 and 5 by v%) and engine load conditions. The combustion parameters, performance and pollutant emissions of PL biodiesel and its blends are compared with those of diesel fuel. The results show that the thermal efficiency is 3% higher for PL biodiesel than for diesel fuel. The emission levels of carbon monoxide (CO), unburned hydrocarbon (HC) and particulate matter are considerably reduced at full engine load (around 25%, 45% and 17% respectively). On the other hand, the brake specific fuel consumption (BSFC) and the nitrogen oxide (NOx) emissions increase (around 10% and 4% respectively).

  20. Improvement of combustion in a direct injection diesel engine by micro-hole nozzle; Micro hole nozzle wo mochiita chokusetsu funshashiki diesel kikan no nensho kaizen

    Energy Technology Data Exchange (ETDEWEB)

    Murata, M. [Keio University, Tokyo (Japan); Kobori, S. [Tokyo Institute of Technology, Tokyo (Japan); Iida, N. [Keio University, Tokyo (Japan). Faculty of Science and Technology

    2000-07-25

    In an attempt to promote the atomization of fuel spray and the mixing of fuel and air in diesel engines, a micro-hole nozzle which has orifices with a diameter smaller than 0.10mm was developed. In this study, the combustion tests were carried out using a single cylinder diesel engine equipped with a micro-hole nozzle and a common rail type high-pressure fuel injection system. A comparison with the results of a conventional nozzle experiment showed that the peak of initial premixed combustion increased, but the peak of diffusion combustion decreased. As a result, when nozzle orifice diameter become small from {phi} 0.15 mm to {phi} 0.10 mm, the combustion was accompanied by smokeless with the same levels of NO{sub x} emission and fuel economy. And results of a comparison the toroidal type chamber with the shallow dish type chamber revealed that the optimization of combustion chamber is necessary for the increase of the injection stage with increasing of the number of nozzle orifice. If an orifice diameter becomes {phi} 0.06 mm, the diffusion combustion can not be observed and the combustion is formed of only premixed combustion. The combustion in the case of {phi} 0.06 mm was accompanied with the drastic deterioration of fuel economy, smoke and HC with all over load. But the micro-hole nozzle has a potential for the formation of the lean and homogeneous premixed mixture until the fuel-air mixture ignites. (author)

  1. Properties of Laser-Produced Highly Charged Heavy Ions for Direct Injection Scheme

    CERN Document Server

    Sakakibara, Kazuhiko; Hayashizaki, Noriyosu; Ito, Taku; Kashiwagi, Hirotsugu; Okamura, Masahiro

    2005-01-01

    To accelerate highly charged intense ion beam, we have developed the Direct Plasma Injection Scheme (DPIS) with laser ion source. In this scheme an ion beam from a laser ion source is injected directly to a RFQ linac without a low energy beam transport (LEBT) and the beam loss in the LEBT can be avoided. We achieved high current acceleration of carbon ions (60mA) by DPIS with the high current optimized RFQ. As the next setp we will use heavier elements like Ag, Pb, Al and Cu as target in LIS (using CO2, Nd-YAG or other laser) for DPIS and will examine properties of laser-produced plasma (the relationship of between charge state and laser power density, the current dependence of the distance from the target, etc).

  2. Jet plume injection and combustion system for internal combustion engines

    Science.gov (United States)

    Oppenheim, Antoni K.; Maxson, James A.; Hensinger, David M.

    1993-01-01

    An improved combustion system for an internal combustion engine is disclosed wherein a rich air/fuel mixture is furnished at high pressure to one or more jet plume generator cavities adjacent to a cylinder and then injected through one or more orifices from the cavities into the head space of the cylinder to form one or more turbulent jet plumes in the head space of the cylinder prior to ignition of the rich air/fuel mixture in the cavity of the jet plume generator. The portion of the rich air/fuel mixture remaining in the cavity of the generator is then ignited to provide a secondary jet, comprising incomplete combustion products which are injected into the cylinder to initiate combustion in the already formed turbulent jet plume. Formation of the turbulent jet plume in the head space of the cylinder prior to ignition has been found to yield a higher maximum combustion pressure in the cylinder, as well as shortening the time period to attain such a maximum pressure.

  3. The role of the fuel injection system for combustion process optimization of highly turbocharged PC diesel engines; Die Rolle des Einspritzsystems bei der Brennverfahrensoptimierung von hochaufgeladenen Pkw-Dieselmotoren

    Energy Technology Data Exchange (ETDEWEB)

    Gerhardt, Juergen; Leonhard, Rolf; Krueger, Michael; Naber, Dirk; Pitt, J. [Robert Bosch GmbH, Stuttgart (Germany)

    2008-07-01

    In order to comply with continuously rising requirements from emission legislation and fuel economy enhancement, modern Diesel engines for passenger cars still offer a variety of measures. Focus of this paper is the importance of a highly flexible fuel-injection system and an optimized injection strategy as direct measures to improve both, tail-pipe emission as well as vehicle fuel economy. An integrated system approach of high pressure pump, injector and nozzle provides the latest injection patterns combined with an increased rail pressure level with a best-in-class hydraulic efficiency. The resulting improvement in the injection system and thus in the combustion also enables the introduction of additional indirect, very effective measures for fuel consumption reduction, such as downsizing and downspeeding. In order to fully utilize the potent of the mentioned approaches, the application of advanced boosting technology is an additional key factor. Bosch Diesel injection technology and optimized combustion systems pave the way to achieve the goal of efficient emission reduction. (orig.)

  4. Particulate emission characteristics of a port-fuel-injected SI engine

    International Nuclear Information System (INIS)

    Gupta, S.; Poola, R.; Lee, K. O.; Sekar, R.

    2000-01-01

    Particulate emissions from spark-ignited (SI) engines have come under close scrutiny as they tend to be smaller than 50 nm, are composed mainly of volatile organic compounds, and are emitted in significant numbers. To assess the impact of such emissions, measurements were performed in the exhaust of a current-technology port-fuel-injected SI engine, which was operated at various steady-state conditions. To gain further insights into the particulate formation mechanisms, measurements were also performed upstream of the catalytic converter. At all engine speeds, a general trend was observed in the number densities and mass concentrations: a moderate increase at low loads followed by a decrease at mid-range loads, which was followed by a steep increase at high loads. Within reasonable bounds, one could attribute such a trend to three different mechanisms. An unidentified mechanism at low loads results in particulate emissions monotonically increasing with load. At medium loads, wherein the engine operates close to stoichiometric conditions, high exhaust temperatures lead to particulate oxidation. At high loads, combustion occurs mostly under fuel-rich conditions, and the contribution from combustion soot becomes significant. Estimates of the number of particles emitted per kilometer by a vehicle carrying the current test engine were found to be lower than those from a comparable diesel vehicle by three orders of magnitude. Similar estimates for mass emissions (grams of particulates emitted per kilometer) were found to be two orders of magnitude lower than the future regulated emission value of 0.006 (g/km) for light-duty diesel vehicles. Moreover, considering the fact that these particles have typical lifetimes of 15 min, the health hazard from particulate emissions from SI engines appears to be low

  5. Fonctionnement transitoire et controle de la richesse des moteurs à allumage commandé à injection multipoint Transient Operation and Air-Fuel Ratio Control of Spark-Ignition Port-Injected Engines

    Directory of Open Access Journals (Sweden)

    Le Moyne L.

    2006-12-01

    Full Text Available Sur les moteurs à allumage commandé à injection multipoint on observe des désadaptations de richesse lors de fonctionnement transitoire. Ces désadaptations sont dues au dépôt, sous forme de film liquide, du carburant injecté dans le collecteur. Elles peuvent être compensées par une gestion adéquate de la masse injectée. Ainsi, afin d'obtenir la masse de carburant qui maintient la richesse constante, nous avons développé un modèle bidimensionnel des écoulements dans le collecteur au cours du cycle moteur. Ce modèle décrit l'écoulement des gaz frais, des gouttes injectées, des gaz brûlés refoulés vers l'admission et du film sur les parois, sur le principe de la séparation des phases. Nous montrons que le modèle reproduit correctement le signal de richesse et comment il permet de supprimer les désadaptations. La mesure de richesse est faite à l'échappement avec une sonde à oxygène dont nous validons le fonctionnement en transitoire avec une corrélation à la pression maximale du cycle dans le cylindre. Air-fuel ratio excursions are observed on port-injected spark ignition engines during transients. This excursions result from the liquid fuel film deposited on intake port. They can be compensated by controlling the injected fuel mass. In order to have the amount of fuel that keeps air-fuel ratio constant, we have developed a 2D model of flows in the intake port during engine cycle. This separate phases model describes the flow of fresh gases, injected droplets, hot burned gases and film on port walls. We show that the model effectively predicts the equivalence ratio and how it allows to eliminate excursions. Equivalence ratio measures are made with an oxygen sensor which functioning is validated during transients by correlating it to maximal pressure during engine cycle.

  6. Combustion characteristics and optimal factors determination with Taguchi method for diesel engines port-injecting hydrogen

    International Nuclear Information System (INIS)

    Wu, Horng-Wen; Wu, Zhan-Yi

    2012-01-01

    This study applies the L 9 orthogonal array of the Taguchi method to find out the best hydrogen injection timing, hydrogen-energy-share ratio, and the percentage of exhaust gas circulation (EGR) in a single DI diesel engine. The injection timing is controlled by an electronic control unit (ECU) and the quantity of hydrogen is controlled by hydrogen flow controller. For various engine loads, the authors determine the optimal operating factors for low BSFC (brake specific fuel consumption), NO X , and smoke. Moreover, net heat-release rate involving variable specific heat ratio is computed from the experimental in-cylinder pressure. In-cylinder pressure, net heat-release rate, A/F ratios, COV (coefficient of variations) of IMEP (indicated mean effective pressure), NO X , and smoke using the optimum condition factors are compared with those by original baseline diesel engine. The predictions made using Taguchi's parameter design technique agreed with the confirmation results on 95% confidence interval. At 45% and 60% loads the optimum factor combination compared with the original baseline diesel engine reduces 14.52% for BSFC, 60.5% for NO X and for 42.28% smoke and improves combustion performance such as peak in-cylinder pressure and net heat-release rate. Adding hydrogen and EGR would not generate unstable combustion due to lower COV of IMEP. -- Highlights: ► We use hydrogen injector controlled by ECU and cooled EGR system in a diesel engine. ► Optimal factors by Taguchi method are determined for low BSFC, NO X and smoke. ► The COV of IMEP is lower than 10% so it will not cause the unstable combustion. ► We improve A/F ratio, in-cylinder pressure, and heat-release at optimized engine. ► Decrease is 14.5% for BSFC, 60.5% for NO X , and 42.28% for smoke at optimized engine.

  7. Numerical Investigation of Injection Timing Influence on Fuel Slip and Influence of Compression Ratio on Knock Occurrence in Conventional Dual Fuel Engine

    Directory of Open Access Journals (Sweden)

    Mario Sremec

    2017-12-01

    Full Text Available Compressed natural gas can be used in diesel engine with great benefits, but because of its low reactivity it is usually used in a so called dual fuel combustion process. Optimal parameters for dual fuel engines are not yet investigated thoroughly which is the motivation for this work. In this work, a numerical study performed in a cycle simulation tool (AVL Boost v2013 on the influence of different injection timings on fuel slip into exhaust and influence of compression ratio on knock phenomena in port injected dual fuel engine was conducted. The introduction of natural gas into the intake port of a diesel engine usually results in some fuel slipping into the exhaust port due to valve overlap. By analysing the simulation results, the injection strategy that significantly decreases the natural gas slip is defined. The knock occurrence study showed that the highest allowed compression ratio that will result in knock free operation of the presented engine is 18 for ambient intake condition, while for charged intake conditions the compression ratio should be lowered to 16.

  8. Compositional Effects of Gasoline Fuels on Combustion, Performance and Emissions in Engine

    KAUST Repository

    Ahmed, Ahfaz; Waqas, Muhammad; Naser, Nimal; Singh, Eshan; Roberts, William L.; Chung, Suk-Ho; Sarathy, Mani

    2016-01-01

    to interpret differences in combustion behavior of gasoline fuels that show similar knock characteristics in a cooperative fuel research (CFR) engine, but may behave differently in direct injection spark ignition (DISI) engines or any other engine combustion

  9. Experimental study of dual fuel engine performance using variable LPG composition and engine parameters

    International Nuclear Information System (INIS)

    Elnajjar, Emad; Selim, Mohamed Y.E.; Hamdan, Mohammad O.

    2013-01-01

    Highlights: • The effect of using variable LPG is studied. • Five fuels with propane to butane % volume ratio are: 100-70-55-25-0. • 100% Propane composition shows the highest noise levels with similar performance. • At 45° BTDC injection timing 55% Propane LPG the only fuel experience knocking. • LPG fuels gave similar engine performance, with differences in levels of noise. - Abstract: The present work investigates experimentally the effect of LPG fuel with different composition and engine parameters on the performance of a dual compression engine. Five different blends of LPG fuels are used with Propane to Butane volume ratio of 100:0, 70:30, 55:45, 25:75, and 0:100. A single cylinder, naturally aspirated, four strokes, indirectly injected, water cooled modified Ricardo E6 engine, is used in this study. The study is carried out by measuring the cylinder pressure, engine load, engine speed, crank angle, and the fuel’s flow rate. The engine performance under variable LPG fuel composition, engine load, pilot fuel injection timing, compression ratio, pilot fuel mass and engine speed, are estimated by comparing the following engine parameters: the cylinder maximum pressure, the indicated mean effective pressure, the maximum rate of pressure rise, and the thermal efficiency. The experimental data indicates that the engine parameters are playing a major role on the engine’s performance. Different LPG fuel composition did not show a major effect on the engine efficiency but directly impacted the levels of generated combustion noise

  10. Investigation of ecological parameters of four-stroke SI engine, with pneumatic fuel injection system

    Science.gov (United States)

    Marek, W.; Śliwiński, K.

    2016-09-01

    The publication presents the results of tests to determine the impact of using waste fuels, alcohol, to power the engine, on the ecological parameters of the combustion engine. Alternatively fuelled with a mixture of iso- and n-butanol, indicated with "X" and "END, and gasoline and a mixture of fuel and alcohol. The object of the study was a four-stroke engine with spark ignition designed to work with a generator. Motor power was held by the modified system of pneumatic injection using hot exhaust gases developed by Prof. Stanislaw Jarnuszkiewicz, controlled by modern mechatronic systems. Tests were conducted at a constant speed for the intended use of the engine. The subject of the research was to determine the control parameters such as ignition timing, mixture composition and the degree of exhaust gas recirculation on the ecological parameters of the engine. Tests were carried out using partially quality power control. In summary we present the findings of this phase of the study.

  11. Weed control by direct injection of plant protection products according to specific situations

    Directory of Open Access Journals (Sweden)

    Krebs, Mathias

    2016-02-01

    Full Text Available Precision Farming in agriculture allows a site-specific management of the crop. The aim of plant protection is to apply plant protection products (PPP according to the site specific requirements on the field. Within the context of a research program to promote innovation, a sprayer with direct injection of plant protection products was developed. The direct injection offers site specific spraying of different individual PPP in a single pass. The sprayer prototype is equipped with a special spray boom combining three nozzle lines. In order to prevent delay times, the nozzle lines are preloaded before spraying. First results for weed control from test stand measurements and field trials showed that the injection pumps work with high accuracy. The prototype can be used without delay times site specific with up to three different herbicides. Field trials for site-specific weed control in winter wheat demonstrate the applicability of the system under practical conditions. By treatment of subareas herbicides and therefore costs could be saved. A reduction in yield compared with the conventionally treated field areas could not be ascertained. Also an efficacy reduction through washout of active ingredient from target surfaces due to simultaneous use of all three nozzle lines with up to 1050 l/ha application rate could not be detected. At high water spray rates, the efficacy effect occurs delayed. Overall, the newly developed direct injection system proved fieldabillity during the first tests. So weed control can be carried out situation-responsive, which can save herbicides and environmental impacts are reduced.

  12. 77 FR 73268 - Airworthiness Directives; Rolls-Royce plc Turbofan Engines

    Science.gov (United States)

    2012-12-10

    ... Airworthiness Directives; Rolls-Royce plc Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT... certain Rolls-Royce plc (RR) RB211-Trent 900 series turbofan engines. This AD requires inspection of the... turbofan engines, all serial numbers. (d) Reason This AD was prompted by a Trent 900 engine experiencing a...

  13. THE EFFECT OF GASOLINE-LIKE FUEL PRODUCED FROM WASTE AUTOMOBILE TIRES ON EMISSIONS IN SPARK-IGNITION ENGINES

    OpenAIRE

    ÖZTOP, H. F.; VAROL, Y.; ALTUN, Ş.; FIRAT, M.

    2016-01-01

    In the present paper, the effect of Gasoline-Like Fuel (GLF) on emissions was investigated for direct injection spark-ignited engine. The GLF was obtained from waste automobile tires by using the pyrolysis. The tires are installed to oven without any procedure such as cutting, melding etc. Obtained GLF was then used in a four-cylinder, four-stroke, water-cooled and direct injection spark-ignited engine as blended with unleaded gasoline from 0% to 60% with an increment of 10%. Engine tests res...

  14. The new 2.5L L4 gasoline engine for LEXUS IS300h. The renewed engine series for FR hybrid vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Ishiguro, Fumihisa; Mashiki, Zenichiro; Yamanari, Kenji [Toyota Motor Corporation, Aichi (Japan)

    2013-08-01

    To ensure future sustainable mobility, vehicles have to face crucial problems such as energy security, global warming and air quality. To address these problems, TOYOTA introduced in 1997 the TOYOTA Hybrid System (THS) and has continuously improved its technology, globally contributing to the environmental improvement by its expansion into many markets in the world. TOYOTA presented the renewed 4 Cylinder Engine Series for FF vehicles at this symposium last year. This year, Toyota presents the result of its continuous development for FR Hybrid Vehicles, especially for D and E segment vehicles. Toyota not only improved thermal efficiency and reduced CO{sub 2} but also achieved high power output. In 2012, TOYOTA launched 3.5L V6 engine for LEXUS-GS (2GR-FXE engine), as first engine of this new engine series. In 2013, TOYOTA will launch 2.5L-L4 engine for LEXUS-IS (2AR-FSE engine), as the leading engine of this series. Toyota developed these new engines, aiming at leadership with regard to fuel economy, clean exhaust gas and high reliability. Toyota carried out modifications, taking into account usage of Hybrid System. With targeting highest levels of environmental performance, Toyota improved the vehicle driving performances like acceleration response by the combination of enhanced engine power output and newly developed Hybrid System. One of the biggest feature of this series is new generation D-4S system, including two injectors (for Direct injection and Port injection) for each cylinder, high fuel pressure (greater than 18MPa) and high fuel flow rate. The new generation D-4S system helps achieving high performance and good thermal efficiency. Furthermore, Toyota added on Cooled EGR system to 2AR-FSE engine, contributing to lower the fuel consumption, especially in highway driving. The very low friction technology and the well proven Atkinson Cycle are also key features of this engine series. Thanks to the above features, the new engine series achieves high

  15. Combustion Noise and Pollutants Prediction for Injection Pattern and Exhaust Gas Recirculation Tuning in an Automotive Common-Rail Diesel Engine

    Directory of Open Access Journals (Sweden)

    Arsie Ivan

    2015-01-01

    Full Text Available In the last years, emissions standards for internal combustion engines are becoming more and more restrictive, particularly for NOx and soot emissions from Diesel engines. In order to comply with these requirements, OEMs have to face with innovative combustion concepts and/or sophisticate after-treatment devices. In both cases, the role of the Engine Management System (EMS is increasingly essential, following the large number of actuators and sensors introduced and the need to meet customer expectations on performance and comfort. On the other hand, the large number of control variables to be tuned imposes a massive recourse to the experimental testing which is poorly sustainable in terms of time and money. In order to reduce the experimental effort and the time to market, the application of simulation models for EMS calibration has become fundamental. Predictive models, validated against a limited amount of experimental data, allow performing detailed analysis on the influence of engine control variables on pollutants, comfort and performance. In this paper, a simulation analysis on the impact of injection pattern and Exhaust Gas Recirculation (EGR rate on fuel consumption, combustion noise, NO and soot emissions is presented for an automotive Common-Rail Diesel engine. Simulations are accomplished by means of a quasi-dimensional multi-zone model of in-cylinder processes. Furthermore a methodology for in-cylinder pressure processing is presented to estimate combustion noise contribution to radiated noise. Model validation is carried out by comparing simulated in-cylinder pressure traces and exhaust emissions with experimental data measured at the test bench in steady-state conditions. Effects of control variables on engine performance, noise and pollutants are analyzed by imposing significant deviation of EGR rate and injection pattern (i.e. rail pressure, start-of-injection, number of injections. The results evidence that quasi-dimensional in

  16. 76 FR 54373 - Airworthiness Directives; Austro Engine GmbH Model E4 Diesel Piston Engines

    Science.gov (United States)

    2011-09-01

    ... diesel piston engines, with high-pressure (HP) fuel pump, part number (P/N) E4A- 30-100-000, installed... Airworthiness Directives; Austro Engine GmbH Model E4 Diesel Piston Engines AGENCY: Federal Aviation... pressure supply for excessive oscillations to determine if high-pressure (HP) fuel pumps have been exposed...

  17. Study on the Effect of water Injection Momentum on the Cooling Effect of Rocket Engine Exhaust Plume

    Science.gov (United States)

    Yang, Kan; Qiang, Yanhui; Zhong, Chenghang; Yu, Shaozhen

    2017-10-01

    For the study of water injection momentum factors impact on flow field of the rocket engine tail flame, the numerical computation model of gas-liquid two phase flow in the coupling of high temperature and high speed gas flow and low temperature liquid water is established. The accuracy and reliability of the numerical model are verified by experiments. Based on the numerical model, the relationship between the flow rate and the cooling effect is analyzed by changing the water injection momentum of the water spray pipes. And the effective mathematical expression is obtained. What’s more, by changing the number of the water spray and using small flow water injection, the cooling effect is analyzed to check the application range of the mathematical expressions. The results show that: the impact and erosion of the gas flow field could be reduced greatly by water injection, and there are two parts in the gas flow field, which are the slow cooling area and the fast cooling area. In the fast cooling area, the influence of the water flow momentum and nozzle quantity on the cooling effect can be expressed by mathematical functions without causing bifurcation flow for the mainstream gas. The conclusion provides a theoretical reference for the engineering application.

  18. Euro VI particulate limits. Methods of development for GDI engines; Euro VI Partikelgrenzwerte. Entwicklungsmethoden fuer GDI Motoren

    Energy Technology Data Exchange (ETDEWEB)

    Fuchs, Heribert; Hopfner, Wolfgang; Kapus, Paul; Kortschak, Martin; Winklhofer, Ernst [AVL List GmbH, Graz (Austria)

    2011-07-01

    Development of direct injection spark ignition (DISI) engines is focussing on techniques to provide mixture quality and charge motion suitable for clean and fuel efficient combustion. A significant number of such DISI engines employ turbo charging. They most often operate under homogeneous and stoichiometric conditions. Charge stratification and fuel rich combustion modes are, however, selected for specific drive conditions and must be included into emissions development strategies. Particle mass and number emissions allowed by forthcoming Euro VI legistation for the NEDC test impose engine out limits which require mixture formation quality otherwise achieved in natural gas engines and in modern port injection engines. Such high quality mixture formation targets with direct injection of liquid fuel need development techniques including all relevant steps from engine concept selection until final vehicle calibration. This paper describes testing techniques supporting such development efforts from first hardware tests on single cylinder optical engines up to in-cylinder evaluation of mixture quality in vehicle calibration work. (orig.)

  19. 77 FR 57007 - Airworthiness Directives; Pratt & Whitney Division Turbofan Engines

    Science.gov (United States)

    2012-09-17

    ... Airworthiness Directives; Pratt & Whitney Division Turbofan Engines AGENCY: Federal Aviation Administration (FAA... turbofan engines. That AD currently requires initial and repetitive fluorescent penetrant inspections (FPI... applies to the following Pratt & Whitney Division (Pratt & Whitney) turbofan engines: (1) PW4000-94...

  20. Case study: Comparison of motivation for achieving higher performance between self-directed and manager-directed aerospace engineering teams

    Science.gov (United States)

    Erlick, Katherine

    "The stereotype of engineers is that they are not people oriented; the stereotype implies that engineers would not work well in teams---that their task emphasis is a solo venture and does not encourage social aspects of collaboration" (Miner & Beyerlein, 1999, p. 16). The problem is determining the best method of providing a motivating environment where design engineers may contribute within a team in order to achieve higher performance in the organization. Theoretically, self-directed work teams perform at higher levels. But, allowing a design engineer to contribute to the team while still maintaining his or her anonymity is the key to success. Therefore, a motivating environment must be established to encourage greater self-actualization in design engineers. The purpose of this study is to determine the favorable motivational environment for design engineers and describe the comparison between two aerospace design-engineering teams: one self-directed and the other manager directed. Following the comparison, this study identified whether self-direction or manager-direction provides the favorable motivational environment for operating as a team in pursuit of achieving higher performance. The methodology used in this research was the case study focusing on the team's levels of job satisfaction and potential for higher performance. The collection of data came from three sources, (a) surveys, (b) researcher observer journal and (c) collection of artifacts. The surveys provided information regarding personal behavior characteristics, potentiality for higher performance and motivational attributes. The researcher journal provided information regarding team dynamics, individual interaction, conflict and conflict resolution. The milestone for performance was based on the collection of artifacts from the two teams. The findings from this study illustrated that whether the team was manager-directed or self-directed does not appear to influence the needs and wants of the

  1. Neutral-beam-injected tokamak fusion reactors: a review

    International Nuclear Information System (INIS)

    Jassby, D.L.

    1976-08-01

    The theories of energetic-ion velocity distributions, stability, injection, and orbits were summarized. The many-faceted role of the energetic ions in plasma heating, fueling, and current maintenance, as well as in the direct enhancement of fusion power multiplication and power density, is discussed in detail for three reactor types. The relevant implications of recent experimental results on several beam-injected tokamaks are examined. The behavior of energetic ions is found to be in accordance with classical theory, large total ion energy densities are readily achieved, and plasma equilibrium and stability are maintained. The status of neutral-beam injectors and of conceptual design studies of beam-driven reactors are briefly reviewed. The principal plasma-engineering problems are those associated directly with achieving quasi-stationary operation

  2. A Comparison of Combustion Dynamics for Multiple 7-Point Lean Direct Injection Combustor Configurations

    Science.gov (United States)

    Tacina, K. M.; Hicks, Y. R.

    2017-01-01

    The combustion dynamics of multiple 7-point lean direct injection (LDI) combustor configurations are compared. LDI is a fuel-lean combustor concept for aero gas turbine engines in which multiple small fuel-air mixers replace one traditionally-sized fuel-air mixer. This 7-point LDI configuration has a circular cross section, with a center (pilot) fuel-air mixer surrounded by six outer (main) fuel-air mixers. Each fuel-air mixer consists of an axial air swirler followed by a converging-diverging venturi. A simplex fuel injector is inserted through the center of the air swirler, with the fuel injector tip located near the venturi throat. All 7 fuel-air mixers are identical except for the swirler blade angle, which varies with the configuration. Testing was done in a 5-atm flame tube with inlet air temperatures from 600 to 800 F and equivalence ratios from 0.4 to 0.7. Combustion dynamics were measured using a cooled PCB pressure transducer flush-mounted in the wall of the combustor test section.

  3. 77 FR 15939 - Airworthiness Directives; Pratt & Whitney Turbofan Engines

    Science.gov (United States)

    2012-03-19

    ... Airworthiness Directives; Pratt & Whitney Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT... & Whitney (PW) JT9D series turbofan engines. That AD currently requires revisions to the Airworthiness..., -7R4E, - 7R4E1, -7R4E4, -7R4G2, and -7R4H1 series turbofan engines. (d) Unsafe Condition This AD results...

  4. Measurement of elemental speciation by liquid chromatography -- inductively coupled plasma mass spectrometry (LC-ICP-MS) with the direct injection nebulizer (DIN)

    Energy Technology Data Exchange (ETDEWEB)

    Shum, Sam [Iowa State Univ., Ames, IA (United States)

    1993-05-01

    This thesis is divided into 4 parts: elemental speciation, speciation of mercury and lead compounds by microbore column LC-ICP-MS with direct injection nebulization, spatially resolved measurements of size and velocity distributions of aerosol droplets from a direct injection nebulizer, and elemental speciation by anion exchange and size exclusion chromatography with detection by ICP-MS with direct injection nebulization.

  5. The new 1.8 l TFSI engine from Audi. Pt. 1. Base engine and thermomanagement

    Energy Technology Data Exchange (ETDEWEB)

    Eiser, Alex; Jung, Michael; Adam, Stephan [Audi AG, Ingolstadt (Germany). Engine Development Dept.; Doerr, Joachim [Audi AG, Ingolstadt (Germany). Longitudinally Mounted Engines Dept.

    2011-06-15

    The launch of the new 1.8 l TFSI engine marks the third generation of the successful four-cylinder gasoline engine family from Audi. It has been completely revised in order to meet ambitious CO{sub 2} targets and ensure compliance with future Euro 6 emissions standards. The new generation features numerous innovative technologies, including an exhaust gas cooling system integrated into the cylinder head, a dual fuel injection system with direct and port-fuel injection as well as the Audi valvelift system with twin camshaft adjustment. A new-style fully electronic coolant control also enables an innovative thermomanagement system to be implemented. This first part of the article details the base engine and the thermomanagement system of the new engine. The second part of the article, which will be published in MTZ 7/8, covers the mixture formation, the combustion method and the turbocharging. (orig.)

  6. Myocardial imaging by direct injection of thallium-201 into coronary artery

    International Nuclear Information System (INIS)

    Sugihara, Hiroki; Inagaki, Suetsugu; Kubota, Yasushi

    1988-01-01

    Myocardial perfusion images were evaluated by direct injection of Thallium (Tl)-201 into coronary artery. Approximately 0.5 - 1 mCi of Tl-201 were instilled into the right coronary artery and/or the left coronary artery after coronary arteriography. Three images were obtained in the anterior, left anterior oblique and left lateral projections. Myocardial perfusion images of single photon emission computed tomography were also acquired in some patients. An image of supreme quality could be obtained in spite of small dose of Tl-201 since there was a lack of interference from background activity. Myocardial perfusion images corresponded to areas which were supplied by left or right coronary artery respectively. And the regional myocardial blood flow distribution of a coronary artery bypass graft could be revealed by instilling Tl-201 into the graft. Further, contribution of collateral channels to myocardial perfusion was showed. Not only left ventricle but also right ventricle was clearly visualized by injection of Tl-201 into right coronary artery. But in a case with arrhythmogenic right ventricular dysplasia, there was an area of decreased tracer uptake in the apex of the right ventricle which was identified as the site of dysplasia by electrophysiologic study. We conclude that direct injection of Tl-201 into coronary artery is an useful method to clarify the correlation between coronary anatomical findings and coronary perfusion and contribution of collaterals to myocardial perfusion, and also to detect the right ventricular myopathic site. (author)

  7. 77 FR 51695 - Airworthiness Directives; Honeywell International Inc. Turbofan Engines

    Science.gov (United States)

    2012-08-27

    ... Airworthiness Directives; Honeywell International Inc. Turbofan Engines AGENCY: Federal Aviation Administration... Honeywell International Inc. TFE731-20R, -20AR, -20BR, -40, -40AR, - 40R, -50R, and -60 turbofan engines... Inc. TFE731-20R, -20AR, -20BR, -40, -40AR, -40R, -50R, and -60 turbofan engines: (i) With an engine...

  8. Organic Spin-Valves and Beyond: Spin Injection and Transport in Organic Semiconductors and the Effect of Interfacial Engineering.

    Science.gov (United States)

    Jang, Hyuk-Jae; Richter, Curt A

    2017-01-01

    Since the first observation of the spin-valve effect through organic semiconductors, efforts to realize novel spintronic technologies based on organic semiconductors have been rapidly growing. However, a complete understanding of spin-polarized carrier injection and transport in organic semiconductors is still lacking and under debate. For example, there is still no clear understanding of major spin-flip mechanisms in organic semiconductors and the role of hybrid metal-organic interfaces in spin injection. Recent findings suggest that organic single crystals can provide spin-transport media with much less structural disorder relative to organic thin films, thus reducing momentum scattering. Additionally, modification of the band energetics, morphology, and even spin magnetic moment at the metal-organic interface by interface engineering can greatly impact the efficiency of spin-polarized carrier injection. Here, progress on efficient spin-polarized carrier injection into organic semiconductors from ferromagnetic metals by using various interface engineering techniques is presented, such as inserting a metallic interlayer, a molecular self-assembled monolayer (SAM), and a ballistic carrier emitter. In addition, efforts to realize long spin transport in single-crystalline organic semiconductors are discussed. The focus here is on understanding and maximizing spin-polarized carrier injection and transport in organic semiconductors and insight is provided for the realization of emerging organic spintronics technologies. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. 77 FR 13485 - Airworthiness Directives; Rolls-Royce plc Turbofan Engines

    Science.gov (United States)

    2012-03-07

    ... Airworthiness Directives; Rolls-Royce plc Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT... series turbofan engines. This AD requires inspecting the front combustion liner head section for cracking.... (c) Applicability This AD applies to Rolls-Royce plc (RR) RB211-Trent 800 turbofan engines, all...

  10. Research directions in computer engineering. Report of a workshop

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, H

    1982-09-01

    The results of a workshop held in November 1981 in Washington, DC, to outline research directions for computer engineering are reported upon. The purpose of the workshop was to provide guidance to government research funding agencies, as well as to universities and industry, as to the directions which computer engineering research should take for the next five to ten years. A select group of computer engineers was assembled, drawn from all over the United States and with expertise in virtually every aspect of today's computer technology. Industrial organisations and universities were represented in roughly equal numbers. The panel proceeded to provide a sharper definition of computer engineering than had been in popular use previously, to identify the social and national needs which provide the basis for encouraging research, to probe for obstacles to research and seek means of overcoming them and to delineate high-priority areas in which computer engineering research should be fostered. These included experimental software engineering, architectures in support of programming style, computer graphics, pattern recognition. VLSI design tools, machine intelligence, programmable automation, architectures for speech and signal processing, computer architecture and robotics. 13 references.

  11. An analytical and experimental study of performance on jatropha biodiesel engine

    Directory of Open Access Journals (Sweden)

    Ganapathy Thirunavukkarasu

    2009-01-01

    Full Text Available Biodiesel plays a major role as one of the alternative fuel options in direct injection diesel engines for more than a decade. Though many feed stocks are employed for making biodiesel worldwide, biodiesel derived from domestically available non-edible feed stocks such as Jatropha curcas L. is the most promising alternative engine fuel option especially in developing countries. Since experimental analysis of the engine is pricey as well as more time consuming and laborious, a theoretical thermodynamic model is necessary to analyze the performance characteristics of jatropha biodiesel fueled diesel engine. There were many experimental studies of jatropha biodiesel fueled diesel engine reported in the literature, yet theoretical study of this biodiesel run diesel engine is scarce. This work presents a theoretical thermodynamic study of single cylinder four stroke direct injection diesel engine fueled with biodiesel derived from jatropha oil. The two zone thermodynamic model developed in the present study computes the in-cylinder pressure and temperature histories in addition to various performance parameters. The results of the model are validated with experimental values for a reasonable agreement. The variation of cylinder pressure with crank angle for various models are also compared and presented. The effects of injection timing, relative air fuel ratio and compression ratio on the engine performance characteristics for diesel and jatropha biodiesel fuels are then investigated and presented in the paper.

  12. NOx reduction by ozone injection and direct plasma treatment

    DEFF Research Database (Denmark)

    Stamate, Eugen; Salewski, Mirko

    2012-01-01

    NOx reduction by ozone injection and direct plasma treatment is investigated for different process parameters in a 6 m long serpentine reactor. Several aspects including the role of mixing scheme, water vapours, steep temperature gradient and time dependet NOx levels are taken into consideration...

  13. STUDY ON THE NITROGEN OXIDES EMISSIONS GENERATED BY THE DIRECT INJECTION DIESEL ENGINES RUNNING WITH BIODIESEL

    Directory of Open Access Journals (Sweden)

    Doru Cosofret

    2016-05-01

    Full Text Available Currently, research results on the use of mixtures of biofuels with fossil fuels to power diesel engines are controversial in terms of reducing emissions of NO in the exhaust gases of diesel engines. This diversity on the results is due to possibly different type of biodiesel used, the type of engine on which the tests were carried out and the methods and conditions for obtaining these results. Therefore research on biodiesel mixed with diesel is still a matter of study. In this regard, we conducted a laboratory study on a 4-stroke diesel engine naturally aspirated, using different mixtures (10, 15, 20, 25, 30, 40 and 50% of diesel with biodiesel made from rapeseed oil. The study results revealed that the NO emissions of the mixtures used are lower than the same emissions produced when the engine is powered with diesel. Also, the emissions of NO do not have a significant drop in the case of mixtures compared with the diesel fuel.

  14. Development and validation of double and single Wiebe function for multi-injection mode Diesel engine combustion modelling for hardware-in-the-loop applications

    International Nuclear Information System (INIS)

    Maroteaux, Fadila; Saad, Charbel; Aubertin, Fabrice

    2015-01-01

    Highlights: • Modelling of Diesel engine combustion with multi-injection mode was conducted. • Double and single Wiebe correlations for pilot, main and post combustion processes were calibrated. • Ignition delay time correlations have been developed and calibrated using experimental data for each injection. • The complete in-cylinder model has been applied successfully to real time simulations on HiL test bed. - Abstract: The improvement of Diesel engine performances in terms of fuel consumption and pollutant emissions has a huge impact on management system and diagnostic procedure. Validation and testing of engine performances can benefit from the use of theoretical models, for the reduction of development time and costs. Hardware in the Loop (HiL) test bench is a suitable way to achieve these objectives. However, the increasing complexity of management systems rises challenges for the development of very reduced physical models able to run in real time applications. This paper presents an extension of a previously developed phenomenological Diesel combustion model suitable for real time applications on a HiL test bench. In the earlier study, the modelling efforts have been targeted at high engine speeds with a very short computational time window, and where the engine operates with single injection. In the present work, a modelling of in-cylinder processes at low and medium engine speeds with multi-injection is performed. In order to reach an adequate computational time, the combustion progress during the pilot and main injection periods has been treated through a double Wiebe function, while the post combustion period has required a single Wiebe function. This paper describes the basic system models and their calibration and validation against experimental data. The use of the developed correlations of Wiebe coefficients and ignition delay times for each combustion phase, included in the in-cylinder crank angle global model, is applied for the prediction

  15. Effect of fuel injection parameters on combustion stability and emissions of a mineral diesel fueled partially premixed charge compression ignition (PCCI) engine

    International Nuclear Information System (INIS)

    Jain, Ayush; Singh, Akhilendra Pratap; Agarwal, Avinash Kumar

    2017-01-01

    Highlights: • NOx and PM emissions were lowest at 700 bar fuel injection pressure (FIP). • PCCI showed lower knocking than compression ignition combustion mode. • Increasing FIP reduced emissions of nitrogen oxides and smoke opacity in PCCI mode. • Increasing FIP reduced nucleation mode particle concentration. • Increasing FIP with advanced main injection timings improved PCCI combustion. - Abstract: This experimental study focuses on developing new combustion concept for compression ignition (CI) engines by achieving partially homogeneous charge, leading to low temperature combustion (LTC). Partially premixed charge compression ignition (PCCI) combustion is a single-stage phenomenon, with combustion shifting towards increasingly premixed combustion phase, resulting in lower in-cylinder temperatures. PCCI leads to relatively lower emissions of oxides of nitrogen (NOx) and particulate matter (PM) simultaneously. To investigate combustion, performance and emission characteristics of the PCCI engine, experiments were performed in a mineral diesel fueled single cylinder research engine, which was equipped with flexible fuel injection equipment (FIE). Effects of fuel injection pressure (FIP) were investigated by changing the FIP from 400 bar to 1000 bar. Experiments were carried out by varying start of main injection (SoMI) timings (from 12° to 24° before top dead center (bTDC)), when using single pilot injection. This experimental study included detailed investigations of particulate characteristics such as particulate number-size distribution using engine exhaust particle sizer (EEPS), particulate bound trace metal analysis using inductively coupled plasma-optical emission spectrometer (ICP-OES), and soot morphology using transmission electron microscopy (TEM). PCCI combustion improved with increasing FIP (up to 700 bar) due to superior fuel atomization however further increasing FIP deteriorated PCCI combustion and engine performance due to intense

  16. 78 FR 5126 - Airworthiness Directives; Rolls-Royce plc Turbofan Engines

    Science.gov (United States)

    2013-01-24

    ... Airworthiness Directives; Rolls-Royce plc Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT... turbofan engines. This AD requires replacement of the fuel oil heat exchanger (FOHE). This AD was prompted...-84 turbofan engines with a fuel oil heat exchanger (FOHE), part number 47111-1241, installed. (d...

  17. A highly efficient six-stroke internal combustion engine cycle with water injection for in-cylinder exhaust heat recovery

    International Nuclear Information System (INIS)

    Conklin, James C.; Szybist, James P.

    2010-01-01

    A concept adding two strokes to the Otto or Diesel engine cycle to increase fuel efficiency is presented here. It can be thought of as a four-stroke Otto or Diesel cycle followed by a two-stroke heat recovery steam cycle. A partial exhaust event coupled with water injection adds an additional power stroke. Waste heat from two sources is effectively converted into usable work: engine coolant and exhaust gas. An ideal thermodynamics model of the exhaust gas compression, water injection and expansion was used to investigate this modification. By changing the exhaust valve closing timing during the exhaust stroke, the optimum amount of exhaust can be recompressed, maximizing the net mean effective pressure of the steam expansion stroke (MEP steam ). The valve closing timing for maximum MEP steam is limited by either 1 bar or the dew point temperature of the expansion gas/moisture mixture when the exhaust valve opens. The range of MEP steam calculated for the geometry of a conventional gasoline engine and is from 0.75 to 2.5 bars. Typical combustion mean effective pressures (MEP combustion ) of naturally aspirated gasoline engines are up to 10 bar, thus this concept has the potential to significantly increase the engine efficiency and fuel economy.

  18. Performance evaluation of a direct injection engine using different blends of soybeans methyl biodiesel; Avaliacao do desempenho de um motor de injecao direta utlizando diferentes misturas de biodiesel metilico de soja

    Energy Technology Data Exchange (ETDEWEB)

    Nietiedt, G.H.; Schlosser, J.F.; Uhry, D.; Casali, A.L.; Ribas, R.L. [Universidade Federal de Santa Maria (UFSM), RS (Brazil)], email: gustavoheller@hotmail.com

    2011-07-01

    The diesel fuel is used widely in the country and the world. However, growing environmental awareness leads to a larger demand for renewable energy resources. The pioneering in the use of ethanol makes Brazil also consolidate itself in the use of the biodiesel in larger scales, in replacement or as a blend with mineral diesel. Thus, this work aimed to evaluate the use of soybeans methyl biodiesel blends and diesel in an ignition compression engine with fuel direct injection. The tests were performed on a dynamometer bench, using the blends B10, B20 and B100 in comparison to the commercial diesel (B5). The engine performance was analyzed by tractor power take off (PTO) for each fuel, and the best results obtained for the power and the specific fuel consumption, respectively, were: B5 (44,62 kW; 234,87 g/kW.h{sup -1}); B10 (44,73 kW; 233,78 g/kW.h{sup -1}); B20 (44,40 kW; 236,20 g/kW.h{sup -1}) e B100 (43,40 kW; 263,63 g/kW.h{sup -1}). The best performance happened on the use of B5 and B10 fuel, without significant differences between these blends. The B100 fuel showed significant differences compared to the other fuels. (author)

  19. Performance Evaluation of a Software Engineering Tool for Automated Design of Cooling Systems in Injection Moulding

    DEFF Research Database (Denmark)

    Jauregui-Becker, Juan M.; Tosello, Guido; van Houten, Fred J.A.M.

    2013-01-01

    This paper presents a software tool for automating the design of cooling systems for injection moulding and a validation of its performance. Cooling system designs were automatically generated by the proposed software tool and by applying a best practice tool engineering design approach. The two...

  20. 发动机早喷过程中燃油喷射混合的大涡模拟%Large eddy simulation for fuel injection and mixing of early-injection in diesel engine

    Institute of Scientific and Technical Information of China (English)

    周磊; 解茂昭; 贾明; 史俊瑞

    2012-01-01

    The feasibility of large eddy simulation (LES) for predicting fuel injection and mixing of early injection in diesel engine was studied. LES turbulent model was implemented into KTVA3V code to make numerical simulation of the atomization and evaporation processes of early injection timing in a constant volume chamber and a ford high-speed direct-injection diesel engine. The results show that the predictive vapor mass fraction and liquid penetration using LES is obviously better than those using RANS model and good agreement with the experiment results. In combustion chamber, the sub-grid turbulent kinetic energy and viscosity using LES is less than those of the RANS models', and with the increase of time, the sub-grid turbulent kinetic energy and viscosity also increase and concentrate on the spray area. Meantime, advancing the injection timing can help to achieve more homogenous mixture between the fuel and ambient gas. The distribution of the mixture is more uniform and the tree-dimension and disorder structures are more obvious using LES model. Compared to RANS model, LES model can better reflect the real spray flow field of early injection process in diesel engine.%对大涡模型在预测发动机早喷中燃料和空气混合过程的适用性进行研究.将大涡模拟(LES)湍流模型加入KIVA3V程序中,对定容弹中燃油短喷以及在1台Ford高速直喷柴油发动机中的早喷过程进行数值模拟.研究结果表明:LES模型预测的喷雾浓度分布和贯穿距与实验结果较相符,明显比RANS模型的优;在燃烧室中LES模型得到的湍动能和黏性都要比RANS模型的小,而且随着喷射时间的增加,亚网格湍动能和黏性都增加并集中在喷射区域;同时,喷油时刻提前有利于燃油与空气的均质混合,LES模型得到的混合气分布更加均匀,三维紊乱的结构更加明显;与RANS模型相比,ES模型更能真实反映柴油机早喷过程中的喷雾流场.

  1. 78 FR 70487 - Airworthiness Directives; Rolls-Royce plc Turbofan Engines

    Science.gov (United States)

    2013-11-26

    ... Airworthiness Directives; Rolls-Royce plc Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT... turbofan engines. This AD requires removal of certain high-pressure (HP) and intermediate-pressure (IP..., RB211 Trent 768-60, 772-60, and 772B-60 turbofan engines with turbine disc part numbers (P/Ns) and...

  2. 77 FR 56760 - Airworthiness Directives; Rolls-Royce plc Turbofan Engines

    Science.gov (United States)

    2012-09-14

    ... Airworthiness Directives; Rolls-Royce plc Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT... all Rolls-Royce plc (RR) RB211-Trent 800 series turbofan engines. This AD requires removing from...-17, 892-17, 892B-17, and 895-17 turbofan engines that have an intermediate pressure (IP) turbine disc...

  3. 78 FR 68360 - Airworthiness Directives; Rolls-Royce plc Turbofan Engines

    Science.gov (United States)

    2013-11-14

    ... Airworthiness Directives; Rolls-Royce plc Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT... turbofan engines. The AD number is incorrect in the Regulatory text. This document corrects that error. In... turbofan engines. As published, the AD number 2013-19-17 under Sec. 39.13 [Amended], is incorrect. No other...

  4. 78 FR 61171 - Airworthiness Directives; Rolls-Royce plc Turbofan Engines

    Science.gov (United States)

    2013-10-03

    ... Airworthiness Directives; Rolls-Royce plc Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT... (RR) RB211-535E4-B-37 series turbofan engines. This AD requires removal of affected parts using a...-B-37 series turbofan engines. (d) Unsafe Condition This AD was prompted by recalculating the lives...

  5. 77 FR 16921 - Airworthiness Directives; Pratt & Whitney Division Turbofan Engines

    Science.gov (United States)

    2012-03-23

    ... Airworthiness Directives; Pratt & Whitney Division Turbofan Engines AGENCY: Federal Aviation Administration (FAA..., PW4160, PW4460, PW4462, and PW4650 turbofan engines, including models with any dash number suffix. This... Compliance We estimate that this AD will affect 44 turbofan engines installed on airplanes of U.S. registry...

  6. 77 FR 20987 - Airworthiness Directives; Rolls-Royce plc Turbofan Engines

    Science.gov (United States)

    2012-04-09

    ... Directives; Rolls-Royce plc Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION... the Federal Register. That AD applies to RB211-Trent 800 series turbofan engines. The last comment...

  7. Advanced stratified charge rotary aircraft engine design study

    Science.gov (United States)

    Badgley, P.; Berkowitz, M.; Jones, C.; Myers, D.; Norwood, E.; Pratt, W. B.; Ellis, D. R.; Huggins, G.; Mueller, A.; Hembrey, J. H.

    1982-01-01

    A technology base of new developments which offered potential benefits to a general aviation engine was compiled and ranked. Using design approaches selected from the ranked list, conceptual design studies were performed of an advanced and a highly advanced engine sized to provide 186/250 shaft Kw/HP under cruise conditions at 7620/25,000 m/ft altitude. These are turbocharged, direct-injected stratified charge engines intended for commercial introduction in the early 1990's. The engine descriptive data includes tables, curves, and drawings depicting configuration, performance, weights and sizes, heat rejection, ignition and fuel injection system descriptions, maintenance requirements, and scaling data for varying power. An engine-airframe integration study of the resulting engines in advanced airframes was performed on a comparative basis with current production type engines. The results show airplane performance, costs, noise & installation factors. The rotary-engined airplanes display substantial improvements over the baseline, including 30 to 35% lower fuel usage.

  8. Effects of biobutanol and biobutanol–diesel blends on combustion and emission characteristics in a passenger car diesel engine with pilot injection strategies

    International Nuclear Information System (INIS)

    Yun, Hyuntae; Choi, Kibong; Lee, Chang Sik

    2016-01-01

    Highlights: • Effects of biobutanol blends on NOx and soot emission characteristics in a diesel engine. • Comparison of combustion characteristics between biobutanol and diesel fuels. • Effect of pilot injection on combustion and emissions reduction in a diesel engine. - Abstract: In this study, we investigated the effect of biobutanol and biobutanol–diesel blends on the combustion and emission characteristics in a four-cylinder compression ignition engine using pilot injection strategies. The test fuels were a mixture of 10% biobutanol and 90% conventional diesel (Bu10), 20% biobutanol and 80% diesel (Bu20), and 100% diesel fuel (Bu0) based on mass. To study the combustion and emission characteristics of the biobutanol blended fuels, we carried out experimental investigations under various pilot injection timings from BTDC 20° to BTDC 60° with constant main injection timing. As the butanol content in the blended fuel increased, the experimental results indicated that the ignition delay was longer than that of diesel fuel for all pilot injection timings. Also, the indicated specific fuel consumption (ISFC) of the blended fuels was higher than that of diesel at all test conditions. However, the exhaust temperature was lower than that of diesel at all injection timings. Nitrogen oxide (NOx), carbon monoxide (CO) and soot from Bu20 were lower than those from diesel fuel at all test conditions and hydrocarbons (HC) were higher than that from diesel.

  9. Sector Tests of a Low-NO(sub x), Lean, Direct- Injection, Multipoint Integrated Module Combustor Concept Conducted

    Science.gov (United States)

    Tacina, Robert R.; Wey, Chang-Lie; Laing, Peter; Mansour, Adel

    2002-01-01

    The low-emissions combustor development described is directed toward advanced high pressure aircraft gas-turbine applications. The emphasis of this research is to reduce nitrogen oxides (NOx) at high-power conditions and to maintain carbon monoxide and unburned hydrocarbons at their current low levels at low power conditions. Low-NOx combustors can be classified into rich-burn and lean-burn concepts. Lean-burn combustors can be further classified into lean-premixed-prevaporized (LPP) and lean direct injection (LDI) concepts. In both concepts, all the combustor air, except for liner cooling flow, enters through the combustor dome so that the combustion occurs at the lowest possible flame temperature. The LPP concept has been shown to have the lowest NOx emissions, but for advanced high-pressure-ratio engines, the possibility of autoignition or flashback precludes its use. LDI differs from LPP in that the fuel is injected directly into the flame zone, and thus, it does not have the potential for autoignition or flashback and should have greater stability. However, since it is not premixed and prevaporized, good atomization is necessary and the fuel must be mixed quickly and uniformly so that flame temperatures are low and NOx formation levels are comparable to those of LPP. The LDI concept described is a multipoint fuel injection/multiburning zone concept. Each of the multiple fuel injectors has an air swirler associated with it to provide quick mixing and a small recirculation zone for burning. The multipoint fuel injection provides quick, uniform mixing and the small multiburning zones provide for reduced burning residence time, resulting in low NOx formation. An integrated-module approach was used for the construction where chemically etched laminates, diffusion bonded together, combine the fuel injectors, air swirlers, and fuel manifold into a single element. The multipoint concept combustor was demonstrated in a 15 sector test. The configuration tested had 36

  10. 78 FR 17297 - Airworthiness Directives; Rolls-Royce plc Turbofan Engines

    Science.gov (United States)

    2013-03-21

    ... Airworthiness Directives; Rolls-Royce plc Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT... (AD) for all Rolls-Royce plc (RR) RB211 Trent 500 series turbofan engines. That AD currently requires... 9, 2012), for all RR RB211 Trent 500 series turbofan engines. That AD requires a one-time inspection...

  11. 77 FR 67763 - Airworthiness Directives; Pratt & Whitney Division Turbofan Engines

    Science.gov (United States)

    2012-11-14

    ... Airworthiness Directives; Pratt & Whitney Division Turbofan Engines AGENCY: Federal Aviation Administration (FAA..., PW4156A, PW4158, PW4160, PW4460, PW4462, and PW4650 turbofan engines, including models with any dash... PW4650 turbofan engines, including models with any dash number suffix, with 3rd stage low-pressure...

  12. 78 FR 76045 - Airworthiness Directives; General Electric Company Turbofan Engines

    Science.gov (United States)

    2013-12-16

    ... Airworthiness Directives; General Electric Company Turbofan Engines AGENCY: Federal Aviation Administration (FAA... (AD) for General Electric Company (GE) GE90-110B1 and GE90-115B turbofan engines with certain high... turbofan engines with high pressure compressor (HPC) rotor stage 2-5 spools, part numbers (P/Ns) 351-103...

  13. 78 FR 11976 - Airworthiness Directives; Rolls-Royce plc Turbofan Engines

    Science.gov (United States)

    2013-02-21

    ... Airworthiness Directives; Rolls-Royce plc Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT... (AD) for all Rolls-Royce plc (RR) RB211-524 series turbofan engines. That AD currently requires...-16724 (76 FR 40217, July 8, 2011), for all RR plc RB211-524 series turbofan engines. That AD required...

  14. 78 FR 50320 - Airworthiness Directives; General Electric Company Turbofan Engines

    Science.gov (United States)

    2013-08-19

    ... Airworthiness Directives; General Electric Company Turbofan Engines AGENCY: Federal Aviation Administration (FAA... Electric Company (GE) model GEnx-2B67B turbofan engines with booster anti-ice (BAI) air duct, part number...-2B67 turbofan engine be removed from the Applicability section of this AD. The commenters noted that...

  15. 77 FR 3088 - Airworthiness Directives; General Electric Company Turbofan Engines

    Science.gov (United States)

    2012-01-23

    ... Airworthiness Directives; General Electric Company Turbofan Engines AGENCY: Federal Aviation Administration (FAA... Electric Company (GE) CF34-10E series turbofan engines. This AD was prompted by a report of heavy wear... turbofan engines installed on airplanes of U.S. registry. We also estimate that it will take about 8 work...

  16. 77 FR 51459 - Airworthiness Directives; Pratt & Whitney Division Turbofan Engines

    Science.gov (United States)

    2012-08-24

    ... Airworthiness Directives; Pratt & Whitney Division Turbofan Engines AGENCY: Federal Aviation Administration (FAA..., PW4460, PW4462, PW4164, PW4164C, PW4164C/B, PW4168, and PW4168A turbofan engines with certain high... ADs None. (c) Applicability This AD applies to the following Pratt & Whitney Division turbofan engines...

  17. Photobiomodulation of mesenchymal stem cells encapsulated in an injectable rhBMP4-loaded hydrogel directs hard tissue bioengineering.

    Science.gov (United States)

    Diniz, Ivana M A; Carreira, Ana C O; Sipert, Carla R; Uehara, Cindi M; Moreira, Maria S N; Freire, Laila; Pelissari, Cibele; Kossugue, Patrícia M; de Araújo, Daniele R; Sogayar, Mari C; Marques, Márcia M

    2018-06-01

    Photobiomodulation (PBM) therapy displays relevant properties for tissue healing and regeneration, which may be of interest for the tissue engineering field. Here, we show that PBM is able to improve cell survival and to interact with recombinant human Bone Morphogenetic Protein 4 (rhBMP4) to direct and accelerate odonto/osteogenic differentiation of dental derived mesenchymal stem cells (MSCs). MSCs were encapsulated in an injectable and thermo-responsive cell carrier (Pluronic ® F-127) loaded with rhBMP4 and then photoactivated. PBM improved MSCs self-renewal and survival upon encapsulation in the Pluronic ® F-127. In the presence of rhBMP4, cell odonto/osteogenic differentiation was premature and markedly improved in the photoactivated MSCs. An in vivo calvarial critical sized defect model demonstrated significant increase in bone formation after PBM treatment. Finally, a balance in the reactive oxygen species levels may be related to the favorable results of PBM and rhBMP4 association. PBM may act in synergism with rhBMP4 and is a promise candidate to direct and accelerate hard tissue bioengineering. © 2017 Wiley Periodicals, Inc.

  18. Cold Start Emissions of Spark-Ignition Engines at Low Ambient Temperatures as an Air Quality Risk

    Directory of Open Access Journals (Sweden)

    Bielaczyc Piotr

    2014-12-01

    Full Text Available SI engines are highly susceptible to excess emissions when started at low ambient temperatures. This phenomenon has multiple air quality and climate forcing implications. Direct injection petrol engines feature a markedly different fuelling strategy, and so their emissions behaviour is somewhat different from indirect injection petrol engines. The excess emissions of direct injection engines at low ambient temperatures should also differ. Additionally, the direct injection fuel delivery process leads to the formation of PM, and DISI engines should show greater PM emissions at low ambient temperatures. This study reports on laboratory experiments quantifying excess emissions of gaseous and solid pollutants over a legislative driving cycle following cold start at a low ambient temperature for both engine types. Over the legislative cycle for testing at -7°C (the UDC, emissions of HC, CO, NOx and CO2 were higher when tested at -7°C than at 24°C. Massive increases in emissions of HC and CO were observed, together with more modest increases in NOx and CO2 emissions. Results from the entire driving cycle showed excess emissions in both phases (though they were much larger for the UDC. The DISI vehicle showed lower increases in fuel consumption than the port injected vehicles, but greater increases in emission of HC and CO. DISI particle number emissions increased by around 50%; DISI particle mass by over 600%. The observed emissions deteriorations varied somewhat by engine type and from vehicle to vehicle. Excesses were greatest following start-up, but persisted, even after several hundred seconds’ driving. The temperature of the intake air appeared to have a limited but significant effect on emissions after the engine has been running for some time. All vehicles tested here comfortably met the relevant EU limits, providing further evidence that these limits are no longer challenging and need updating.

  19. Evaluation of an accident management strategy of emergency water injection using fire engines in a typical pressurized water reactor

    Directory of Open Access Journals (Sweden)

    Soo-Yong Park

    2015-10-01

    Full Text Available Following the Fukushima accident, a special safety inspection was conducted in Korea. The inspection results show that Korean nuclear power plants have no imminent risk for expected maximum potential earthquake or coastal flooding. However long- and short-term safety improvements do need to be implemented. One of the measures to increase the mitigation capability during a prolonged station blackout (SBO accident is installing injection flow paths to provide emergency cooling water of external sources using fire engines to the steam generators or reactor cooling systems. This paper illustrates an evaluation of the effectiveness of external cooling water injection strategies using fire trucks during a potential extended SBO accident in a 1,000 MWe pressurized water reactor. With regard to the effectiveness of external cooling water injection strategies using fire engines, the strategies are judged to be very feasible for a long-term SBO, but are not likely to be effective for a short-term SBO.

  20. Evaluation of an accident management strategy of emergency water injection using fire engines in a typical pressurized water reactor

    International Nuclear Information System (INIS)

    Park, Soo Yong; Ahn, Kwang Il

    2015-01-01

    Following the Fukushima accident, a special safety inspection was conducted in Korea. The inspection results show that Korean nuclear power plants have no imminent risk for expected maximum potential earthquake or coastal flooding. However long- and short-term safety improvements do need to be implemented. One of the measures to increase the mitigation capability during a prolonged station blackout (SBO) accident is installing injection flow paths to provide emergency cooling water of external sources using fire engines to the steam generators or reactor cooling systems. This paper illustrates an evaluation of the effectiveness of external cooling water injection strategies using fire trucks during a potential extended SBO accident in a 1,000 MWe pressurized water reactor. With regard to the effectiveness of external cooling water injection strategies using fire engines, the strategies are judged to be very feasible for a long-term SBO, but are not likely to be effective for a short-term SBO

  1. Evaluation of an accident management strategy of emergency water injection using fire engines in a typical pressurized water reactor

    Energy Technology Data Exchange (ETDEWEB)

    Park, Soo Yong; Ahn, Kwang Il [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    Following the Fukushima accident, a special safety inspection was conducted in Korea. The inspection results show that Korean nuclear power plants have no imminent risk for expected maximum potential earthquake or coastal flooding. However long- and short-term safety improvements do need to be implemented. One of the measures to increase the mitigation capability during a prolonged station blackout (SBO) accident is installing injection flow paths to provide emergency cooling water of external sources using fire engines to the steam generators or reactor cooling systems. This paper illustrates an evaluation of the effectiveness of external cooling water injection strategies using fire trucks during a potential extended SBO accident in a 1,000 MWe pressurized water reactor. With regard to the effectiveness of external cooling water injection strategies using fire engines, the strategies are judged to be very feasible for a long-term SBO, but are not likely to be effective for a short-term SBO.

  2. 77 FR 42424 - Airworthiness Directives; Pratt & Whitney Turbofan Engines

    Science.gov (United States)

    2012-07-19

    ... Airworthiness Directives; Pratt & Whitney Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT... & Whitney Division PW4074 and PW4077 turbofan engines. That AD currently requires removing the 15th stage..., August 4, 2011). (c) Applicability This AD applies to Pratt & Whitney Division PW4074 and PW4077 turbofan...

  3. 77 FR 32007 - Airworthiness Directives; Rolls-Royce plc Turbofan Engines

    Science.gov (United States)

    2012-05-31

    ... Airworthiness Directives; Rolls-Royce plc Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT... all Rolls-Royce plc (RR) RB211-Trent 800 series turbofan engines. This AD requires removal from...-17, 877- 17, 884-17, 884B-17, 892-17, 892B-17, and 895-17 turbofan engines. (d) Reason This AD was...

  4. 77 FR 39157 - Airworthiness Directives; Rolls-Royce plc Turbofan Engines

    Science.gov (United States)

    2012-07-02

    ... Airworthiness Directives; Rolls-Royce plc Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT...-84, and 980-84 turbofan engines. That AD currently requires inspecting the intermediate-pressure (IP... RR model RB211-Trent 970-84, 970B-84, 972-84, 972B-84, 977-84, 977B-84, and 980-84 turbofan engines...

  5. 78 FR 6749 - Airworthiness Directives; Rolls-Royce plc Turbofan Engines

    Science.gov (United States)

    2013-01-31

    ... Airworthiness Directives; Rolls-Royce plc Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT... (AD) for all Rolls-Royce plc (RR) models RB211 Trent 768-60, 772-60, and 772B-60 turbofan engines... 772B-60 turbofan engines. (d) Reason This AD was prompted by low-pressure (LP) compressor blade partial...

  6. 77 FR 4650 - Airworthiness Directives; General Electric Company Turbofan Engines

    Science.gov (United States)

    2012-01-31

    ... Airworthiness Directives; General Electric Company Turbofan Engines AGENCY: Federal Aviation Administration (FAA... General Electric Company (GE) CF6-45 and CF6-50 series turbofan engines with certain low-pressure turbine... Compliance We estimate that this AD will affect 387 CF6-45 and CF6-50 series turbofan engines installed on...

  7. 78 FR 72567 - Airworthiness Directives; General Electric Company Turbofan Engines

    Science.gov (United States)

    2013-12-03

    ... Airworthiness Directives; General Electric Company Turbofan Engines AGENCY: Federal Aviation Administration (FAA... General Electric Company (GE) GE90-110B1 and -115B turbofan engines. This AD was prompted by multiple... turbofan engines with variable bypass valve (VBV) actuator fuel supply tube, part number (P/N) 2165M22P01...

  8. 77 FR 54791 - Airworthiness Directives; Pratt & Whitney Division Turbofan Engines

    Science.gov (United States)

    2012-09-06

    ... Airworthiness Directives; Pratt & Whitney Division Turbofan Engines AGENCY: Federal Aviation Administration (FAA... & Whitney Division PW4000-94'' and PW4000-100'' turbofan engines having a 1st stage high-pressure turbine... AD will affect 446 P&W PW4000-94'' and PW4000-100'' turbofan engines installed on airplanes of U.S...

  9. 77 FR 6668 - Airworthiness Directives; Rolls-Royce plc Turbofan Engines

    Science.gov (United States)

    2012-02-09

    ... Airworthiness Directives; Rolls-Royce plc Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT... all Rolls-Royce plc RB211-Trent 500 series turbofan engines. This AD requires a one-time inspection of... RB211- Trent 560A2-61 turbofan engines that have not complied with Rolls- Royce plc Service Bulletin No...

  10. 77 FR 51892 - Airworthiness Directives; Honeywell International Inc. Turbofan Engines

    Science.gov (United States)

    2012-08-28

    ... Airworthiness Directives; Honeywell International Inc. Turbofan Engines AGENCY: Federal Aviation Administration... Honeywell International Inc. models TFE731-4, -4R, -5, -5R, -5AR, and - 5BR series turbofan engines. This AD... International Inc.: (1) Model TFE731-5 series turbofan engines, with a first stage low-pressure turbine (LPT1...

  11. Engineering of beam direct conversion for a 120-kV, 1-MW ion beam

    International Nuclear Information System (INIS)

    Barr, W.L.; Doggett, J.N.; Hamilton, G.W.; Kinney, J.D.; Moir, R.W.

    1977-01-01

    Practical systems for beam direct conversion are required to recover the energy from ion beams at high efficiency and at very high beam power densities in the environment of a high-power, neutral-injection system. Such an experiment is now in progress using a 120-kV beam with a maximum total current of 20 A. After neutralization, the H + component to be recovered will have a power of approximately 1MW. A system testing these concepts has been designed and tested at 15 kV, 2 kW in preparation for the full-power tests. The engineering problems involved in the full-power tests affect electron suppression, gas pumping, voltage holding, diagnostics, and measurement conditions. Planning for future experiments at higher power includes the use of cryopumping and electron suppression by a magnetic field rather than by an electrostatic field. Beam direct conversion for large fusion experiments and reactors will save millions of dollars in the cost of power supplies and electricity and will dispose of the charged beam under conditions that may mot be possible by other techniques

  12. Engineering of beam direct conversion for a 120-kV, 1-MW ion beam

    International Nuclear Information System (INIS)

    Barr, W.L.; Doggett, J.N.; Hamilton, G.W.; Kinney, J.D.; Moir, R.W.

    1977-01-01

    Practical systems for beam direct conversion are required to recover the energy from ion beams at high efficiency and at very high beam power densities in the environment of a high-power, neutral-injection system. Such an experiment is now in progress using a 120-kV beam with a maximum total current of 20 A. After neutralization, the H + component to be recovered will have a power of approximately 1 MW. A system testing these concepts has been designed and tested at 15 kV, 2 kW in preparation for the full-power tests. The engineering problems involved in the full-power tests affect electron suppression, gas pumping, voltage holding, diagnostics, and measurement conditions. Planning for future experiments at higher power includes the use of cryopumping and electron suppression by a magnetic field rather than by an electrostatic field. Beam direct conversion for large fusion experiments and reactors will save millions of dollars in the cost of power supplies and electricity and will dispose of the charged beam under conditions that may not be possible by other techniques

  13. Quantitative Imaging of Turbulent Mixing Dynamics in High-Pressure Fuel Injection to Enable Predictive Simulations of Engine Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Frank, Jonathan H. [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Reacting Flows Dept.; Pickett, Lyle M. [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Engine Combustion Dept.; Bisson, Scott E. [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Remote Sensing and Energetic Materials Dept.; Patterson, Brian D. [Sandia National Lab. (SNL-CA), Livermore, CA (United States). combustion Chemistry Dept.; Ruggles, Adam J. [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Reacting Flows Dept.; Skeen, Scott A. [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Engine Combustion Dept.; Manin, Julien Luc [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Engine Combustion Dept.; Huang, Erxiong [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Reacting Flows Dept.; Cicone, Dave J. [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Engine Combustion Dept.; Sphicas, Panos [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Engine Combustion Dept.

    2015-09-01

    In this LDRD project, we developed a capability for quantitative high - speed imaging measurements of high - pressure fuel injection dynamics to advance understanding of turbulent mixing in transcritical flows, ignition, and flame stabilization mechanisms, and to provide e ssential validation data for developing predictive tools for engine combustion simulations. Advanced, fuel - efficient engine technologies rely on fuel injection into a high - pressure, high - temperature environment for mixture preparation and com bustion. Howe ver, the dynamics of fuel injection are not well understood and pose significant experimental and modeling challenges. To address the need for quantitative high - speed measurements, we developed a Nd:YAG laser that provides a 5ms burst of pulses at 100 kHz o n a robust mobile platform . Using this laser, we demonstrated s patially and temporally resolved Rayleigh scattering imaging and particle image velocimetry measurements of turbulent mixing in high - pressure gas - phase flows and vaporizing sprays . Quantitativ e interpretation of high - pressure measurements was advanced by reducing and correcting interferences and imaging artifacts.

  14. Nanoscale Science, Engineering and Technology Research Directions

    Energy Technology Data Exchange (ETDEWEB)

    Lowndes, D. H.; Alivisatos, A. P.; Alper, M.; Averback, R. S.; Jacob Barhen, J.; Eastman, J. A.; Imre, D.; Lowndes, D. H.; McNulty, I.; Michalske, T. A.; Ho, K-M; Nozik, A. J.; Russell, T. P.; Valentin, R. A.; Welch, D. O.; Barhen, J.; Agnew, S. R.; Bellon, P.; Blair, J.; Boatner, L. A.; Braiman, Y.; Budai, J. D.; Crabtree, G. W.; Feldman, L. C.; Flynn, C. P.; Geohegan, D. B.; George, E. P.; Greenbaum, E.; Grigoropoulos, C.; Haynes, T. E.; Heberlein, J.; Hichman, J.; Holland, O. W.; Honda, S.; Horton, J. A.; Hu, M. Z.-C.; Jesson, D. E.; Joy, D. C.; Krauss, A.; Kwok, W.-K.; Larson, B. C.; Larson, D. J.; Likharev, K.; Liu, C. T.; Majumdar, A.; Maziasz, P. J.; Meldrum, A.; Miller, J. C.; Modine, F. A.; Pennycook, S. J.; Pharr, G. M.; Phillpot, S.; Price, D. L.; Protopopescu, V.; Poker, D. B.; Pui, D.; Ramsey, J. M.; Rao, N.; Reichl, L.; Roberto, J.; Saboungi, M-L; Simpson, M.; Strieffer, S.; Thundat, T.; Wambsganss, M.; Wendleken, J.; White, C. W.; Wilemski, G.; Withrow, S. P.; Wolf, D.; Zhu, J. H.; Zuhr, R. A.; Zunger, A.; Lowe, S.

    1999-01-01

    This report describes important future research directions in nanoscale science, engineering and technology. It was prepared in connection with an anticipated national research initiative on nanotechnology for the twenty-first century. The research directions described are not expected to be inclusive but illustrate the wide range of research opportunities and challenges that could be undertaken through the national laboratories and their major national scientific user facilities with the support of universities and industry.

  15. Advanced diesel electronic fuel injection and turbocharging

    Science.gov (United States)

    Beck, N. J.; Barkhimer, R. L.; Steinmeyer, D. C.; Kelly, J. E.

    1993-12-01

    The program investigated advanced diesel air charging and fuel injection systems to improve specific power, fuel economy, noise, exhaust emissions, and cold startability. The techniques explored included variable fuel injection rate shaping, variable injection timing, full-authority electronic engine control, turbo-compound cooling, regenerative air circulation as a cold start aid, and variable geometry turbocharging. A Servojet electronic fuel injection system was designed and manufactured for the Cummins VTA-903 engine. A special Servojet twin turbocharger exhaust system was also installed. A series of high speed combustion flame photos was taken using the single cylinder optical engine at Michigan Technological University. Various fuel injection rate shapes and nozzle configurations were evaluated. Single-cylinder bench tests were performed to evaluate regenerative inlet air heating techniques as an aid to cold starting. An exhaust-driven axial cooling air fan was manufactured and tested on the VTA-903 engine.

  16. Fuel injection assembly for use in turbine engines and method of assembling same

    Science.gov (United States)

    Berry, Jonathan Dwight; Johnson, Thomas Edward; York, William David; Uhm, Jong Ho

    2015-12-15

    A fuel injection assembly for use in a turbine engine is provided. The fuel injection assembly includes an end cover, an endcap assembly, a fluid supply chamber, and a plurality of tube assemblies positioned at the endcap assembly. Each of the tube assemblies includes housing having a fuel plenum and a cooling fluid plenum. The cooling fluid plenum is positioned downstream from the fuel plenum and separated from the fuel plenum by an intermediate wall. The plurality of tube assemblies also include a plurality of tubes that extends through the housing. Each of the plurality of tubes is coupled in flow communication with the fluid supply chamber and a combustion chamber positioned downstream from the tube assembly. The plurality of tube assemblies further includes an aft plate at a downstream end of the cooling fluid plenum. The plate includes at least one aperture.

  17. 77 FR 16139 - Airworthiness Directives; Pratt & Whitney (PW) Turbofan Engines

    Science.gov (United States)

    2012-03-20

    ... Airworthiness Directives; Pratt & Whitney (PW) Turbofan Engines AGENCY: Federal Aviation Administration (FAA... & Whitney (PW) PW2037, PW2037(M), and PW2040 turbofan engines with certain fan blades with a cutback leading..., PW2040, PW2240, PW2337 Turbofan Engine Manual, Part No. 1A6231, Chapter/Section 72-31-12, Repair-14 and...

  18. 78 FR 70489 - Airworthiness Directives; Rolls-Royce plc Turbofan Engines

    Science.gov (United States)

    2013-11-26

    ... Airworthiness Directives; Rolls-Royce plc Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT..., and 560A2-61 turbofan engines. This AD requires replacement or repair of the low-pressure (LP...-61, 556B2-61, 560-61, and 560A2-61 turbofan engines. (d) Reason This AD was prompted by reports of...

  19. 77 FR 58762 - Airworthiness Directives; Rolls-Royce plc Turbofan Engines

    Science.gov (United States)

    2012-09-24

    ... Airworthiness Directives; Rolls-Royce plc Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT...-Trent 892-17, RB211- Trent 892B-17, and RB211-Trent 895-17 turbofan engines. That AD currently requires...-17, RB211-Trent 892B-17, and RB211-Trent 895-17 turbofan engines. (d) Unsafe Condition This AD was...

  20. 78 FR 72552 - Airworthiness Directives; General Electric Company Turbofan Engines

    Science.gov (United States)

    2013-12-03

    ... Airworthiness Directives; General Electric Company Turbofan Engines AGENCY: Federal Aviation Administration (FAA... General Electric Company model GEnx-2B67 and GEnx-2B67B turbofan engines. This AD was prompted by the... certain serial number General Electric Company (GE) model GEnx-2B67 and GEnx-2B67B turbofan engines. The...

  1. 78 FR 49111 - Airworthiness Directives; Pratt & Whitney Division Turbofan Engines

    Science.gov (United States)

    2013-08-13

    ... Airworthiness Directives; Pratt & Whitney Division Turbofan Engines AGENCY: Federal Aviation Administration (FAA... & Whitney Division (PW) turbofan engine model PW4074, PW4074D, PW4077, PW4077D, PW4084D, PW4090, and PW4090...) Applicability This AD applies to all Pratt & Whitney Division (PW) turbofan engine models PW4074, PW4074D...

  2. 78 FR 38195 - Airworthiness Directives; General Electric Company Turbofan Engines

    Science.gov (United States)

    2013-06-26

    ... Directives; General Electric Company Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT... all General Electric Company (GE) GE90-110B1 and GE90-115B turbofan engines. This emergency AD was.... owners and operators of these GE90-110B1 and GE90-115B turbofan engines. This action was prompted by...

  3. 77 FR 9868 - Airworthiness Directives; Honeywell International Inc. Turbofan Engines

    Science.gov (United States)

    2012-02-21

    ... Airworthiness Directives; Honeywell International Inc. Turbofan Engines AGENCY: Federal Aviation Administration... -5BR series turbofan engines. This proposed AD was prompted by a report of a rim/web separation of a..., -4R, -5AR, -5BR, and -5R series turbofan engines, with an LPT1 rotor assembly, P/N 3074748-4, 3074748...

  4. 77 FR 58471 - Airworthiness Directives; General Electric Company Turbofan Engines

    Science.gov (United States)

    2012-09-21

    ... Airworthiness Directives; General Electric Company Turbofan Engines AGENCY: Federal Aviation Administration (FAA.../P1, GEnx-1B75/P1, GEnx- 2B67, and GEnx-2B67B turbofan engines. This AD requires initial and... this AD will affect 11 GE GEnx turbofan engines installed on airplanes of U.S. registry. We also...

  5. Development and Validation of 3D-CFD Injection and Combustion Models for Dual Fuel Combustion in Diesel Ignited Large Gas Engines

    Directory of Open Access Journals (Sweden)

    Lucas Eder

    2018-03-01

    Full Text Available This paper focuses on improving the 3D-Computational Fluid Dynamics (CFD modeling of diesel ignited gas engines, with an emphasis on injection and combustion modeling. The challenges of modeling are stated and possible solutions are provided. A specific approach for modeling injection is proposed that improves the modeling of the ballistic region of the needle lift. Experimental results from an inert spray chamber are used for model validation. Two-stage ignition methods are described along with improvements in ignition delay modeling of the diesel ignited gas engine. The improved models are used in the Extended Coherent Flame Model with the 3 Zones approach (ECFM-3Z. The predictive capability of the models is investigated using data from single cylinder engine (SCE tests conducted at the Large Engines Competence Center (LEC. The results are discussed and further steps for development are identified.

  6. An experimental study on the effects of high-pressure and multiple injection strategies on DI diesel engine emissions

    KAUST Repository

    Yang, Seung Yeon

    2013-03-25

    An experimental study on effects of high-pressure injections in conjunction with split fuel injections were conducted on an AVL single cylinder DI diesel engine. Various injection schemes were studied through the use of an electronically controlled, common rail injection system capable of injection pressures up to 200 MPa and a maximum of six injections per combustion event. Up to 100 MPa of the fuel injection pressure, the higher injection pressures create faster combustion rates that result in the higher in-cylinder gas temperatures as compared to conventional low-pressure fuel injection systems. When applying high-pressure injections, particulate emission reductions of up to 50% were observed with no change in hydrocarbon emissions, reductions of CO emissions and only slightly higher NOx emissions. Over 100 MPa, on the other hand, the higher injection pressures still reduced up to almost zero-level of particulate emission, at the same time that the NO emission is reduced greatly. Under these high-pressure injection conditions, strong correlations between soot and CO emissions were observed, which compete for the oxidizing OH species. Multiple or split high-pressure injections also investigated as a means to decrease particulate emissions. As a result, a four-split injection strategy resulted in a 55% reduction in particulates and with little or no penalty on NOx emissions. The high pressure split injection strategy with EGR was more effective in reducing particulate and CO emissions simultaneously. Copyright © 2013 SAE International and Copyright © 2013 TSAE.

  7. Use of tobacco seed oil methyl ester in a turbocharged indirect injection diesel engine

    International Nuclear Information System (INIS)

    Usta, N.

    2005-01-01

    Vegetable oils and their methyl/ethyl esters are alternative renewable fuels for compression ignition engines. Different kinds of vegetable oils and their methyl/ethyl esters have been tested in diesel engines. However, tobacco seed oil and tobacco seed oil methyl ester have not been tested in diesel engines, yet. Tobacco seed oil is a non-edible vegetable oil and a by-product of tobacco leaves production. To the author's best knowledge, this is the first study on tobacco seed oil methyl ester as a fuel in diesel engines. In this study, potential tobacco seed production throughout the world, the oil extraction process from tobacco seed and the transesterification process for biodiesel production were examined. The produced tobacco seed oil methyl ester was characterized by exposing its major properties. The effects of tobacco seed oil methyl ester addition to diesel No. 2 on the performance and emissions of a four cycle, four cylinder turbocharged indirect injection (IDI) diesel engine were examined at both full and partial loads. Experimental results showed that tobacco seed oil methyl ester can be partially substituted for the diesel fuel at most operating conditions in terms of performance parameters and emissions without any engine modification and preheating of the blends. (Author)

  8. Numerical Simulations of Hollow-Cone Injection and Gasoline Compression Ignition Combustion With Naphtha Fuels

    KAUST Repository

    Badra, Jihad A.

    2016-01-29

    Gasoline compression ignition (GCI), also known as partially premixed compression ignition (PPCI) and gasoline direct injection compression ignition (GDICI), engines have been considered an attractive alternative to traditional spark ignition (SI) engines. Lean-burn combustion with the direct injection of fuel eliminates throttle losses for higher thermodynamic efficiencies, and the precise control of the mixture compositions allows better emission performance such as NOx and particulate matter (PM). Recently, low octane gasoline fuel has been identified as a viable option for the GCI engine applications due to its longer ignition delay characteristics compared to diesel and lighter evaporation compared to gasoline fuel (Chang et al., 2012, "Enabling High Efficiency Direct Injection Engine With Naphtha Fuel Through Partially Premixed Charge Compression Ignition Combustion," SAE Technical Paper No. 2012-01-0677). The feasibility of such a concept has been demonstrated by experimental investigations at Saudi Aramco (Chang et al., 2012, "Enabling High Efficiency Direct Injection Engine With Naphtha Fuel Through Partially Premixed Charge Compression Ignition Combustion," SAE Technical Paper No. 2012-01-0677; Chang et al., 2013, "Fuel Economy Potential of Partially Premixed Compression Ignition (PPCI) Combustion With Naphtha Fuel," SAE Technical Paper No. 2013-01-2701). The present study aims to develop predictive capabilities for low octane gasoline fuel compression ignition (CI) engines with accurate characterization of the spray dynamics and combustion processes. Full three-dimensional simulations were conducted using converge as a basic modeling framework, using Reynolds-averaged Navier-Stokes (RANS) turbulent mixing models. An outwardly opening hollow-cone spray injector was characterized and validated against existing and new experimental data. An emphasis was made on the spray penetration characteristics. Various spray breakup and collision models have been

  9. 78 FR 6206 - Airworthiness Directives; Rolls-Royce plc Turbofan Engines

    Science.gov (United States)

    2013-01-30

    ... Airworthiness Directives; Rolls-Royce plc Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT..., RB211-Trent 977-84, RB211-Trent 977B-84 and RB211-Trent 980-84 turbofan engines. This AD requires on...

  10. 78 FR 5 - Airworthiness Directives; Rolls-Royce plc Turbofan Engines

    Science.gov (United States)

    2013-01-02

    ... Airworthiness Directives; Rolls-Royce plc Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT...-535E4-C-37 turbofan engines. This AD was prompted by an investigation by RR concluding that certain...- 535E4-B-37; RB211-535E4-B-75; and RB211-535E4-C-37 turbofan engines with intermediate-pressure (IP...

  11. 78 FR 37703 - Airworthiness Directives; Rolls-Royce plc Turbofan Engines

    Science.gov (United States)

    2013-06-24

    ... Airworthiness Directives; Rolls-Royce plc Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT... (RR) model RB211 Trent 768-60, 772-60, and 772B-60 turbofan engines. This AD was prompted by low...) model RB211 Trent 768-60, 772-60, and 772B-60 turbofan engines. (d) Reason This AD was prompted by low...

  12. 77 FR 12448 - Airworthiness Directives; Pratt & Whitney Division Turbofan Engines

    Science.gov (United States)

    2012-03-01

    ... Airworthiness Directives; Pratt & Whitney Division Turbofan Engines AGENCY: Federal Aviation Administration (FAA..., PW4160, PW4460, PW4462, and PW4650 turbofan engines, including models with any dash number suffix. This..., PW4062, PW4062A, PW4152, PW4156, PW4156A, PW4158, PW4160, PW4460, PW4462, and PW4650 turbofan engines...

  13. 78 FR 22180 - Airworthiness Directives; Rolls-Royce plc Turbofan Engines

    Science.gov (United States)

    2013-04-15

    ... Airworthiness Directives; Rolls-Royce plc Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT... 972B-84, RB211-Trent 977-84, RB211-Trent 977B-84, and RB211-Trent 980-84 turbofan engines. This AD... 977B-84, and RB211-Trent 980-84 turbofan engines that incorporate RR production Modification 72-G585 or...

  14. 78 FR 24671 - Airworthiness Directives; General Electric Company Turbofan Engines

    Science.gov (United States)

    2013-04-26

    ... Airworthiness Directives; General Electric Company Turbofan Engines AGENCY: Federal Aviation Administration (FAA... certain General Electric Company (GE) CF6-80C2 series turbofan engines. That AD currently requires.../B1F/B2F/B4F/B6F/B7F/D1F turbofan engines with any of the following installed: (1) Fuel tube, part...

  15. 77 FR 20508 - Airworthiness Directives; Rolls-Royce plc Turbofan Engines

    Science.gov (United States)

    2012-04-05

    ... Airworthiness Directives; Rolls-Royce plc Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT...-Trent 884B-17, RB211-Trent 892-17, RB211- Trent 892B-17, and RB211-Trent 895-17 turbofan engines. That...-17, RB211- Trent 892B-17, and RB211-Trent 895-17 turbofan engines. On September 9, 2011, we also...

  16. 78 FR 19983 - Airworthiness Directives; General Electric Company Turbofan Engines

    Science.gov (United States)

    2013-04-03

    ... Airworthiness Directives; General Electric Company Turbofan Engines AGENCY: Federal Aviation Administration (FAA... Electric Company (GE) CF34-8C and CF34-8E turbofan engines with certain part numbers (P/N) of operability...-8E6, and CF34-8E6A1 turbofan engines, with an operability bleed valve (OBV) part number (P/N...

  17. 78 FR 79295 - Airworthiness Directives; CFM International S.A. Turbofan Engines

    Science.gov (United States)

    2013-12-30

    ... Airworthiness Directives; CFM International S.A. Turbofan Engines AGENCY: Federal Aviation Administration (FAA... International (CFM) S.A. CFM56-3 and CFM56-7B series turbofan engines with certain accessory gearboxes (AGBs... of total loss of engine oil from CFM56 series turbofan engines while in flight. This AD requires an...

  18. Injectable alginate-O-carboxymethyl chitosan/nano fibrin composite hydrogels for adipose tissue engineering.

    Science.gov (United States)

    Jaikumar, Dhanya; Sajesh, K M; Soumya, S; Nimal, T R; Chennazhi, K P; Nair, Shantikumar V; Jayakumar, R

    2015-03-01

    Injectable, biodegradable scaffolds are required for soft tissue reconstruction owing to its minimally invasive approach. Such a scaffold can mimic the native extracellular matrix (ECM), provide uniform distribution of cells and overcome limitations like donor site morbidity, volume loss, etc. So, here we report two classes of biocompatible and biodegradable hydrogel blend systems namely, Alginate/O-carboxymethyl chitosan (O-CMC) and Alginate/poly (vinyl alcohol) (PVA) with the inclusion of fibrin nanoparticles in each. The hydrogels were prepared by ionic cross-linking method. The developed hydrogels were compared in terms of its swelling ratio, degradation profile, compressive strength and elastic moduli. From these preliminary findings, it was concluded that Alginate/O-CMC formed a better blend for tissue engineering applications. The potential of the formed hydrogel as an injectable scaffold was revealed by the survival of adipose derived stem cells (ADSCs) on the scaffold by its adhesion, proliferation and differentiation into adipocytes. Cell differentiation studies of fibrin incorporated hydrogel scaffolds showed better differentiation was confirmed by Oil Red O staining technique. These injectable gels have potential in soft tissue regeneration. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. An Injectable Enzymatically Crosslinked Carboxymethylated Pullulan/Chondroitin Sulfate Hydrogel for Cartilage Tissue Engineering

    Science.gov (United States)

    Chen, Feng; Yu, Songrui; Liu, Bing; Ni, Yunzhou; Yu, Chunyang; Su, Yue; Zhu, Xinyuan; Yu, Xiaowei; Zhou, Yongfeng; Yan, Deyue

    2016-01-01

    In this study, an enzymatically cross-linked injectable and biodegradable hydrogel system comprising carboxymethyl pullulan-tyramine (CMP-TA) and chondroitin sulfate-tyramine (CS-TA) conjugates was successfully developed under physiological conditions in the presence of both horseradish peroxidase (HRP) and hydrogen peroxide (H2O2) for cartilage tissue engineering (CTTE). The HRP crosslinking method makes this injectable system feasible, minimally invasive and easily translatable for regenerative medicine applications. The physicochemical properties of the mechanically stable hydrogel system can be modulated by varying the weight ratio and concentration of polymer as well as the concentrations of crosslinking reagents. Additionally, the cellular behaviour of porcine auricular chondrocytes encapsulated into CMP-TA/CS-TA hydrogels demonstrates that the hydrogel system has a good cyto-compatibility. Specifically, compared to the CMP-TA hydrogel, these CMP-TA/CS-TA composite hydrogels have enhanced cell proliferation and increased cartilaginous ECM deposition, which significantly facilitate chondrogenesis. Furthermore, histological analysis indicates that the hydrogel system exhibits acceptable tissue compatibility by using a mouse subcutaneous implantation model. Overall, the novel injectable pullulan/chondroitin sulfate composite hydrogels presented here are expected to be useful biomaterial scaffold for regenerating cartilage tissue.

  20. Potentials of cooled EGR and water injection for knock resistance and fuel consumption improvements of gasoline engines

    International Nuclear Information System (INIS)

    Bozza, Fabio; De Bellis, Vincenzo; Teodosio, Luigi

    2016-01-01

    Highlights: • 1D simulation of a turbocharged VVA engine under knock limited operation. • Description of turbulence, combustion and knock by phenomenological models. • Comparison of EGR and ported water injection at high load for knock mitigation and fuel economy. • Virtual calibration of engine control parameters by a 1D model. - Abstract: It is well known that the downsizing philosophy allows the improvement of the brake specific fuel consumption (BSFC) at part load operation for spark ignition (SI) engines. On the other hand, the BSFC is penalized at high load because of the knock occurrence and of further limitations on the turbine inlet temperature (TIT). Knock control forces the adoption of a late combustion phasing, causing a deterioration of the thermodynamic efficiency, while the TIT control requires the enrichment of the air-to-fuel ratio (A/F), with additional BSFC drawbacks. In this work, two promising techniques are investigated by a 1D approach with the aim of improving the fuel economy of a turbocharged SI engine at full load knock-limited operation. The first technique is the recirculation of low-pressure cooled exhaust gas (EGR), while the second is the injection of liquid water at the intake ports. Proper “in-house developed” sub-models are used to describe the turbulence, combustion and knock phenomena. The effects of the above techniques are studied in six operating points at full load and different speeds for various A/F levels and inert content, by varying the EGR rate and water-to-fuel ratio. The presented results highlight that both the solutions involve significant BSFC improvements, especially in the operating conditions at medium engine speeds. In fact, the introduction of inert gas in the cylinder contributes to reduce the knock tendency, resulting in the possibility to advance the combustion phasing and reduce, or even avoid, the mixture over-fuelling. The heat subtracted by the water evaporation enhances the above effects