On the effects of fuel properties and injection timing in partially premixed compression ignition of low octane fuels

KAUST Repository

Naser, Nimal

2017-06-29

A better understanding on the effects of fuel properties and injection timing is required to improve the performance of advanced engines based on low temperature combustion concepts. In this work, an experimental and computational study was conducted to investigate the effects of physical and chemical kinetic properties of low octane fuels and their surrogates in partially premixed compression ignition (PPCI) engines. The main objective was to identify the relative importance of physical versus chemical kinetic properties in predicting practical fuel combustion behavior across a range of injection timings. Two fuel/surrogate pairs were chosen for comparison: light naphtha (LN) versus the primary reference fuel (PRF) with research octane number of 65 (PRF 65), and FACE (fuels for advanced combustion engines) I gasoline versus PRF 70. Two sets of parametric studies were conducted: the first varied the amount of injected fuel mass at different injection timings to match a fixed combustion phasing, and the second maintained the same injected fuel mass at each injection timing to assess resulting combustion phasing changes. Full-cycle computational fluid dynamic engine simulations were conducted by accounting for differences in the physical properties of the original and surrogate fuels, while employing identical chemical kinetics. The simulations were found to capture trends observed in the experiments, while providing details on spatial mixing and chemical reactivity for different fuels and injection timings. It was found that differences in physical properties become increasingly important as injection timing was progressively delayed from premixed conditions, and this was rationalized by analysis of mixture stratification patterns resulting from injection of fuels with different physical properties. The results suggest that accurate descriptions of both physical and chemical behavior of fuels are critical in predictive simulations of PPCI engines for a wide range of

On the effects of fuel properties and injection timing in partially premixed compression ignition of low octane fuels

KAUST Repository

Naser, Nimal; Jaasim, Mohammed; Atef, Nour; Chung, Suk-Ho; Im, Hong G.; Sarathy, Mani

2017-01-01

A better understanding on the effects of fuel properties and injection timing is required to improve the performance of advanced engines based on low temperature combustion concepts. In this work, an experimental and computational study was conducted to investigate the effects of physical and chemical kinetic properties of low octane fuels and their surrogates in partially premixed compression ignition (PPCI) engines. The main objective was to identify the relative importance of physical versus chemical kinetic properties in predicting practical fuel combustion behavior across a range of injection timings. Two fuel/surrogate pairs were chosen for comparison: light naphtha (LN) versus the primary reference fuel (PRF) with research octane number of 65 (PRF 65), and FACE (fuels for advanced combustion engines) I gasoline versus PRF 70. Two sets of parametric studies were conducted: the first varied the amount of injected fuel mass at different injection timings to match a fixed combustion phasing, and the second maintained the same injected fuel mass at each injection timing to assess resulting combustion phasing changes. Full-cycle computational fluid dynamic engine simulations were conducted by accounting for differences in the physical properties of the original and surrogate fuels, while employing identical chemical kinetics. The simulations were found to capture trends observed in the experiments, while providing details on spatial mixing and chemical reactivity for different fuels and injection timings. It was found that differences in physical properties become increasingly important as injection timing was progressively delayed from premixed conditions, and this was rationalized by analysis of mixture stratification patterns resulting from injection of fuels with different physical properties. The results suggest that accurate descriptions of both physical and chemical behavior of fuels are critical in predictive simulations of PPCI engines for a wide range of

Pressure Fluctuations in a Common-Rail Fuel Injection System

Science.gov (United States)

Rothrock, A M

1931-01-01

This report presents the results of an investigation to determine experimentally the instantaneous pressures at the discharge orifice of a common-rail fuel injection system in which the timing valve and cut-off valve were at some distance from the automatic fuel injection valve, and also to determine the methods by which the pressure fluctuations could be controlled. The results show that pressure wave phenomena occur between the high-pressure reservoir and the discharge orifice, but that these pressure waves can be controlled so as to be advantageous to the injection of the fuel. The results also give data applicable to the design of such an injection system for a high-speed compression-ignition engine.

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.

A multi-objective CFD optimization of liquid fuel spray injection in dry-low-emission gas-turbine combustors

International Nuclear Information System (INIS)

Asgari, Behrad; Amani, Ehsan

2017-01-01

Highlights: •An Eulerian-Lagrangian model for the fuel spray injection is evaluated. •The drop breakup, spray-vortex interaction, and wall-wetting play the key roles. •The injection location and direction are the most important parameters. •The best design candidates are proposed using multi-objective optimizations. •A large central perpendicular injection with high co-rotating swirls is optimal. -- Abstract: The main goal of this research is to investigate the effects of fuel injection strategy on the performance of the premixing chamber of modern Dry-Low-Emission (DLE) Gas-Turbine (GT) combustors. Here, an Eulerian-Lagrangian model for multi-phase multi-component flows is evaluated and used to investigate the effects of different fuel spray design parameters, including the injection location, direction, mass-flow-rate partitioning, and flow Swirl number, on the performance of the premixing chamber. The analysis is enriched by multi-objective optimizations accounting for several goals, including the evaporation efficiency, mixture stratification, entropy generation, and flow recirculation. It is observed that the droplet breakup, spray-vortex interactions, and wall-wetting have significant influences on the performance objectives while the droplet residence time effect is minor. Among the design parameters, the injection location and direction have a profound impact on the droplet breakup which predominately controls the evaporation efficiency. In addition, the interactions between the spray and the two swirling vertices inside the chamber strongly affect the mixture stratification (uniformity), e.g. the location and direction of the injection should not be chosen such that a large proportion of fuel droplets are trapped in the shear layer between the two vortices (otherwise the evaporation efficiency drops significantly) or trapped in the strong outer swirling vortex (if large mixture non-uniformity should be avoided). Finally, the best designs meeting

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

Generation of a rotating liquid liner by tangential injection

International Nuclear Information System (INIS)

Burton, R.L.; Turchi, P.J.; Jenkins, D.J.; Lanham, R.E.; Cameron, J.; Cooper, A.L.

1979-01-01

Efficient compression of low mass-density payloads by the implosion of higher mass-density liquid cylinders or liners, as in the NRL LINUS concept for controlled thermonuclear fusion, requires rotation of the liner material to avoid Rayleigh--Taylor instabilities at the liner-payload interface. Experimentally, such implosions have been demonstrated with liners formed within rotating implosion chambers. The present work uses a scale-model experimental apparatus to investigate the possibility of creating liner rotation by tangential injection of the liquid liner material. Different modes of behavior are obtained depending on the fluid exhaust procedures. Right-circular, cylindrical free surfaces are achieved with axial exhaust of fluid at radii interior to the injection nozzles, for which the liner exhibits a combination of solid-body and free vortex flows in different regions. Measurements allow estimates of power losses to viscous shear, turbulence, etc. A simple model based on open-channel flow is then derived, which is in good agreement with experiment, and is used to extrapolate results to the scale of a possible LINUS fusion reactor

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)

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)

Dextrose Prolotherapy Versus Control Injections in Painful Rotator Cuff Tendinopathy.

Science.gov (United States)

Bertrand, Helene; Reeves, Kenneth Dean; Bennett, Cameron J; Bicknell, Simon; Cheng, An-Lin

2016-01-01

To compare the effect of dextrose prolotherapy on pain levels and degenerative changes in painful rotator cuff tendinopathy against 2 potentially active control injection procedures. Randomized controlled trial, blinded to participants and evaluators. Outpatient pain medicine practice. Persons (N=73) with chronic shoulder pain, examination findings of rotator cuff tendinopathy, and ultrasound-confirmed supraspinatus tendinosis/tear. Three monthly injections either (1) onto painful entheses with dextrose (Enthesis-Dextrose), (2) onto entheses with saline (Enthesis-Saline), or (3) above entheses with saline (Superficial-Saline). All solutions included 0.1% lidocaine. All participants received concurrent programmed physical therapy. Primary: participants achieving an improvement in maximal current shoulder pain ≥2.8 (twice the minimal clinically important difference for visual analog scale pain) or not. Secondary: improvement in the Ultrasound Shoulder Pathology Rating Scale (USPRS) and a 0-to-10 satisfaction score (10, completely satisfied). The 73 participants had moderate to severe shoulder pain (7.0±2.0) for 7.6±9.6 years. There were no baseline differences between groups. Blinding was effective. At 9-month follow-up, 59% of Enthesis-Dextrose participants maintained ≥2.8 improvement in pain compared with Enthesis-Saline (37%; P=.088) and Superficial-Saline (27%; P=.017). Enthesis-Dextrose participants' satisfaction was 6.7±3.2 compared with Enthesis-Saline (4.7±4.1; P=.079) and Superficial-Saline (3.9±3.1; P=.003). USPRS findings were not different between groups (P=.734). In participants with painful rotator cuff tendinopathy who receive physical therapy, injection of hypertonic dextrose on painful entheses resulted in superior long-term pain improvement and patient satisfaction compared with blinded saline injection over painful entheses, with intermediate results for entheses injection with saline. These differences could not be attributed to a

BWR fuel experience with zinc injection

International Nuclear Information System (INIS)

Levin, H.A.; Garcia, S.E.

1995-01-01

In 1982 a correlation between low primary recirculation system dose rates in BWR's and the presence of ionic zinc in reactor water was identified. The source of the zinc was primarily from Admiralty brass condensers. Plants with brass condensers are called ''natural zinc'' plants. Brass condensers were also a source of copper that was implicated in crude induced localized corrosion (CILC) fuel failures. In 1986 the first BWR intentionally injected zinc for the benefits of dose rate control. Although zinc alone was never implicated in fuel degradation of failures, a comprehensive fuel surveillance program was initiated to monitor fuel performance. Currently there are 14 plants that are injecting zinc. Six of these plants are also on hydrogen water chemistry. This paper describes the effect on both Zircaloy corrosion and the cruding characteristics as a result of these changes in water chemistry. Fuel rod corrosion was found to be independent of the specific water chemistry of the plants. The corrosion behavior was the same with the additions of zinc alone or zinc plus hydrogen and well within the operating experience for fuel without either of these additions. No change was observed in the amounts of crude deposited on the fuel rods, both for the adherent and loosely held deposits. One of the effects of the zinc addition was the trend to form more of the zinc rich iron spinel in the fuel deposits rather than the hematite deposits that are predominantly formed with non additive water chemistry

Performance of fuel system at different diesel temperature

Science.gov (United States)

Xu, Xiaoyong; Li, Xiaolu; Sun, Zai

2010-08-01

This paper presents the findings about performance of the fuel system of a diesel engine at different diesel temperature obtained through simulation and experiment. It can be seen from these findings that at the same rotational speed of fuel pump, the initial pressure in the fuel pipe remain unchanged as the fuel temperature increases, the peak pressure at the side of fuel pipe near the injector delays, and its largest value of pressure decreases. Meanwhile, at the same temperature, as the rotational speed increases, the initial pressure of fuel pipe is also essentially the same, the arrival of its peaks delays, and its largest value of pressure increases. The maximum fuel pressure at the side of fuel pipe near the injector has an increase of 28.9 %, 22.3%, and 13.9% respectively than the previous ones according to its conditions. At the same rotational speed, as the temperature increases, the injection quantity through the nozzle orifice decreases. At the same temperature, as the rotational speed increases, the injection quantity through the nozzle orifice increases. These experimental results are consistent with simulation results.

Effect of aviation fuel type and fuel injection conditions on the spray characteristics of pressure swirl and hybrid air blast fuel injectors

Science.gov (United States)

Feddema, Rick

Feddema, Rick T. M.S.M.E., Purdue University, December 2013. Effect of Aviation Fuel Type and Fuel Injection Conditions on the Spray Characteristics of Pressure Swirl and Hybrid Air Blast Fuel Injectors. Major Professor: Dr. Paul E. Sojka, School of Mechanical Engineering Spray performance of pressure swirl and hybrid air blast fuel injectors are central to combustion stability, combustor heat management, and pollutant formation in aviation gas turbine engines. Next generation aviation gas turbine engines will optimize spray atomization characteristics of the fuel injector in order to achieve engine efficiency and emissions requirements. Fuel injector spray atomization performance is affected by the type of fuel injector, fuel liquid properties, fuel injection pressure, fuel injection temperature, and ambient pressure. Performance of pressure swirl atomizer and hybrid air blast nozzle type fuel injectors are compared in this study. Aviation jet fuels, JP-8, Jet A, JP-5, and JP-10 and their effect on fuel injector performance is investigated. Fuel injector set conditions involving fuel injector pressure, fuel temperature and ambient pressure are varied in order to compare each fuel type. One objective of this thesis is to contribute spray patternation measurements to the body of existing drop size data in the literature. Fuel droplet size tends to increase with decreasing fuel injection pressure, decreasing fuel injection temperature and increasing ambient injection pressure. The differences between fuel types at particular set conditions occur due to differences in liquid properties between fuels. Liquid viscosity and surface tension are identified to be fuel-specific properties that affect the drop size of the fuel. An open aspect of current research that this paper addresses is how much the type of aviation jet fuel affects spray atomization characteristics. Conventional aviation fuel specifications are becoming more important with new interest in alternative

A new concept of auxiliary fuel injection through tuyeres in blast furnaces developed by numerical simulations

Directory of Open Access Journals (Sweden)

Bruno Orlando de Almeida Santos

2014-04-01

Full Text Available The Injection of powdered materials in blast furnaces is a great option for reducing costs, increasing productivity and satisfy the environmental norms. Thus, this paper presents a study on the use of a flame stabilization system with rotation, designed to promote greater coal injection in the combustion zone, reducing losses and increasing the efficiency of the equipment. A physical model was used to evaluate scattering of pulverized fuel and is compared with numerical results in the same scale. In the second step, a combustion model was added to the numerical simulation, using dimensions of a real blast furnace. Fields like temperature, velocity and behavior of chemical reactions were analyzed. The results showed that double lances promote better particle injection when compared with simple lance for reduced material injection. The new injection system proposed, with swirl numbers of 0.12 and 0.24, promoted a better injection of both reduced material and temperature in the raceway zone. The swirl 0.24 showed superior performance when compared to other injection systems.

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.

Fuel ion rotation measurement and its implications on H-mode theories

International Nuclear Information System (INIS)

Kim, J.; Burrell, K.H.; Gohil, P.; Groebner, R.J.; Hinton, F.L.; Kim, Y.B.; Seraydarian, R.; Mandl, W.

1993-10-01

Poloidal and toroidal rotation of the fuel ions (He 2+ ) and the impurity ions (C 6+ and B 5+ ) in H-mode helium plasmas have been investigated in the DIII-D tokamak by means of charge exchange recombination spectroscopy, resulting in the discovery that the fuel ion poloidal rotation is in the ion diamagnetic drift direction while the impurity ion rotation is in the electron diamagnetic drift direction. The radial electric field obtained from radial force balance analysis of the measured pressure gradients and rotation velocities is shown to be the same regardless of which ion species is used and therefore is a more fundamental parameter than the rotation flows in studying H-mode phenomena. It is shown that the three contributions to the radial electric field (diamagnetic, poloidal rotation, and toroidal rotation terms) are comparable and consequently the poloidal flow does not solely represent the E x B flow. In the high-shear edge region, the density scale length is comparable to the ion poloidal gyroradius, and thus neoclassical theory is not valid there. In view of this new discovery that the fuel and impurity ions rotate in opposite sense, L-H transition theories based on the poloidal rotation may require improvement

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.

Experimental validation of combustion control with multi-pulse fuel injection

NARCIS (Netherlands)

Luo, X.; Velayutham, S.; Willems, F.P.T.

2017-01-01

Closed-loop combustion control helps to achieve precise fuel injection and robust engine performance against disturbances. The controller design complexity increases greatly with larger number of fuel injection pulses due to the coupled influence of changing individual pulse on the combustion

Method of controlling injection of oxygen into hydrogen-rich fuel cell feed stream

Science.gov (United States)

Meltser, Mark Alexander; Gutowski, Stanley; Weisbrod, Kirk

2001-01-01

A method of operating a H.sub.2 --O.sub.2 fuel cell fueled by hydrogen-rich fuel stream containing CO. The CO content is reduced to acceptable levels by injecting oxygen into the fuel gas stream. The amount of oxygen injected is controlled in relation to the CO content of the fuel gas, by a control strategy that involves (a) determining the CO content of the fuel stream at a first injection rate, (b) increasing the O.sub.2 injection rate, (c) determining the CO content of the stream at the higher injection rate, (d) further increasing the O.sub.2 injection rate if the second measured CO content is lower than the first measured CO content or reducing the O.sub.2 injection rate if the second measured CO content is greater than the first measured CO content, and (e) repeating steps a-d as needed to optimize CO consumption and minimize H.sub.2 consumption.

Diesel/CNG Mixture Autoignition Control Using Fuel Composition and Injection Gap

Directory of Open Access Journals (Sweden)

Firmansyah

2017-10-01

Full Text Available Combustion phasing is the main obstacle to the development of controlled auto-ignition based (CAI engines to achieve low emissions and low fuel consumption operation. Fuel combinations with substantial differences in reactivity, such as diesel/compressed natural gas (CNG, show desirable combustion outputs and demonstrate great possibility in controlling the combustion. This paper discusses a control method for diesel/CNG mixture combustion with a variation of fuel composition and fuel stratification levels. The experiments were carried out in a constant volume combustion chamber with both fuels directly injected into the chamber. The mixture composition was varied from 0 to 100% CNG/diesel at lambda 1 while the fuel stratification level was controlled by the injection phasing between the two fuels, with gaps between injections ranging from 0 to 20 ms. The results demonstrated the suppressing effect of CNG on the diesel combustion, especially at the early combustion stages. However, CNG significantly enhanced the combustion performance of the diesel in the later stages. Injection gaps, on the other hand, showed particular behavior depending on mixture composition. Injection gaps show less effect on combustion phasing but a significant effect on the combustion output for higher diesel percentage (≥70%, while it is contradictive for lower diesel percentage (<70%.

Investigation of High Pressure, Multi-Hole Diesel Fuel Injection Using High Speed Imaging

Science.gov (United States)

Morris, Steven; Eagle, Ethan; Wooldridge, Margaret

2012-10-01

Research to experimentally capture and understand transient fuel spray behavior of modern fuel injection systems remains underdeveloped. To this end, a high-pressure diesel common-rail fuel injector was instrumented in a spherical, constant volume combustion chamber to image the early time history of injection of diesel fuel. The research-geometry fuel injector has four holes aligned on a radial plane of the nozzle with hole sizes of 90, 110, 130 and 150 μm in diameter. Fuel was injected into a non-reacting environment with ambient densities of 17.4, 24.0, and 31.8 kg/m3 at fuel rail pressures of 1000, 1500, and 2000 bar. High speed images of fuel injection were taken using backlighting at 100,000 frames per second (100 kfps) and an image processing algorithm. The experimental results are compared with a one-dimensional fuel-spray model that was historically developed and applied to fuel sprays from single-hole fuel injectors. Fuel spray penetration distance was evaluated as a function of time for the different injector hole diameters, fuel injection pressures and ambient densities. The results show the differences in model predictions and experimental data at early times in the spray development.

Steam injection and enhanced bioremediation of heavy fuel oil contamination

International Nuclear Information System (INIS)

Dablow, J.; Hicks, R.; Cacciatore, D.

1995-01-01

Steam injection has been shown to be successful in remediating sites impacted by heavy fuel oils. Field demonstrations at both pilot and full scale have removed No. 2 diesel fuel and Navy Special Fuel Oil (No. 5 fuel oil) from impacted soils. Removal mechanisms include enhanced volatilization of vapor- and adsorbed-phase contaminants and enhanced mobility due to decreased viscosity and associated residual saturation of separate- and adsorbed-phase contaminants. Laboratory studies have shown that indigenous biologic populations are significantly reduced, but are not eliminated by steam injection operations. Populations were readily reestablished by augmentation with nutrients. This suggests that biodegradation enhanced by warm, moist, oxygenated environments can be expected to further reduce concentrations of contaminants following cessation of steam injection operations

Fuel injection nozzle and method of manufacturing the same

Science.gov (United States)

Monaghan, James Christopher; Johnson, Thomas Edward; Ostebee, Heath Michael

2017-02-21

A fuel injection head for use in a fuel injection nozzle comprises a monolithic body portion comprising an upstream face, an opposite downstream face, and a peripheral wall extending therebetween. A plurality of pre-mix tubes are integrally formed with and extend axially through the body portion. Each of the pre-mix tubes comprises an inlet adjacent the upstream face, an outlet adjacent the downstream face, and a channel extending between the inlet and the outlet. Each pre-mix tube also includes at least one fuel injector that at least partially extends outward from an exterior surface of the pre-mix tube, wherein the fuel injector is integrally formed with the pre-mix tube and is configured to facilitate fuel flow between the body portion and the channel.

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).

Simulation of the injection casting of metallic fuels

International Nuclear Information System (INIS)

Nakagawa, Tomokazu; Ogata, Takanari; Tokiwai, Moriyasu.

1989-01-01

For the fabrication of metallic fuel pins, injection casting is a preferable process because the simplicity of the process is suitable for remote operation. In this process, the molten metal in the crucible is injected into evacuated molds (suspended above the crucible) by pressurizing the casting furnace. Argonne National Laboratory has already adopted this process in the Integral Fast Reactor program. To obtain fuel pins with good quality, the casting parameters, such as the molten metal temperature, the magnitude of the pressure applied, the pressurizing rate, the cooling time, etc., must be optimized. Otherwise, bad-quality castings (short castings, rough surfaces, shrinkage cavities, mold fracture) may result. Therefore, it is very important in designing the casting equipment and optimizing the operation conditions to be able to predict the fluid and thermal behavior of the castings. This paper describes methods to simulate the heat and mass transfer in the molds and molten metallic fuel during injection casting. The results obtained by simulation are compared with experimental ones. Also, appropriate casting conditions for the uranium-plutonium-zirconium alloy are discussed based on the simulated results

Poloidal rotation induced by injecting lower hybrid waves in tokamak plasma edge

International Nuclear Information System (INIS)

Jiao Yiming; Gao Qingdi; Shi Bingren

2001-01-01

The poloidal rotation of the magnetized edge plasma in tokamak driven by the ponderomotive force which is generated by injecting lower hybrid wave (LHW) electric field has been studied. The LHW is launched from a waveguide in the plasma edge, and by Brambilla's grill theory, analytic expressions for the wave electric field in the slab model of an inhomogeneous cold plasma have been derived. It is shown that a strong wave electric field will be generated in the plasma edge by injecting LH wave of the power in MW magnitude, and this electric field will induce a poloidal rotation with a sheared poloidal velocity

Production of a rapidly rotating plasma by cross-field injection of gun-produced plasma

International Nuclear Information System (INIS)

Ohzu, Akira; Ikehata, Takashi; Tanabe, Toshio; Mase, Hiroshi

1984-01-01

Cross-field plasma injection with use of a JxB plasma gun is described as a method to produce rapidly rotating plasma in a crossed electric and magnetic field system. The rotational velocity of the plasma is seriously limited by neutrals surrounding the plasma through strong interactions at the boundary layer. The concentration of neutrals can be reduced by the injection of fully or partially ionized plasma into the discharge volume instead of filling the volume with an operating gas. With use of this method, it is observed that the rotational velocity increases by a factor of 2 to 3 when compared with the conventional method of stationary gas-filling. (author)

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.

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

Mitigation of rotational instability of high-beta field-reversed configuration by double-sided magnetized plasmoid injection

Energy Technology Data Exchange (ETDEWEB)

Itagaki, H.; Inomoto, M. [Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561 (Japan); Asai, T.; Takahashi, Ts. [College of Science and Technology, Nihon University, 1-8-14 Kanda Surugadai, Chiyoda-ku, Tokyo 101-8308 (Japan)

2014-03-15

Active control of destructive rotational instability in a high-beta field-reversed configuration (FRC) plasma was demonstrated by using double-sided plasmoid injection technique. The elliptical deformation of the FRC's cross section was mitigated as a result of substantial suppression of spontaneous spin-up by the plasmoid injection. It was found that the injected plasmoid provided better stability against the rotational mode, suggesting that the compensation of the FRC's decaying magnetic flux might help to suppress its spin-up.

Momentum transfer to rotating magnetized plasma from gun plasma injection

International Nuclear Information System (INIS)

Shamim, Imran; Hassam, A. B.; Ellis, R. F.; Witherspoon, F. D.; Phillips, M. W.

2006-01-01

Numerical simulations are carried out to investigate the penetration and momentum coupling of a gun-injected plasma slug into a rotating magnetized plasma. An experiment along these lines is envisioned for the Maryland Centrifugal Experiment (MCX) [R. F. Ellis et al., Phys. Plasmas 8, 2057 (2001)] using a coaxial plasma accelerator gun developed by HyperV Technologies Corp. [F. D. Witherspoon et al., Bull. Am. Phys. Soc. 50, LP1 87 (2005)]. The plasma gun would be located in the axial midplane and fired off-axis into the rotating MCX plasma annulus. The numerical simulation is set up so that the initial momentum in the injected plasma slug is of the order of the initial momentum of the target plasma. Several numerical firings are done into the cylindrical rotating plasma. Axial symmetry is assumed. The slug is seen to penetrate readily and deform into a mushroom, characteristic of interchange deformations. It is found that up to 25% of the momentum in the slug can be transferred to the background plasma in one pass across a cylindrical chord. For the same initial momentum, a high-speed low density slug gives more momentum transfer than a low-speed high density slug. Details of the numerical simulations and a scaling study are presented

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.)

Influence of engine speed and the course of the fuel injection characteristics on forming the average combustion temperature in the cylinder of turbo diesel engine

Directory of Open Access Journals (Sweden)

Piotr GUSTOF

2007-01-01

Full Text Available Average combustion temperatures inside a turbo diesel engine for the same load and the same total doze of fuel for two rotational speeds: 2004 [rpm] and 4250 [rpm] are presented in this paper. The aim of this work is also the evaluation of the influence of the temporary course of the fuel injection characteristics on forming temperature in theengine cylinder space for these temperatures. The calculations were carried out by means of two zone combustion model.

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.

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.

Testing and modelling of a novel oil-free co-rotating scroll machine with water injection

International Nuclear Information System (INIS)

Mendoza, Luis Carlos; Lemofouet, Sylvain; Schiffmann, Jürg

2017-01-01

Highlights: • Performance of novel oil-free co-rotating scroll expander presented. • Water injection allows reaching quasi-isothermal expansion process. • Comparison between experimental data, semi-empirical and deterministic models. • Flank leakage, water injection and rotor speed effects have been analyzed experimentally. • Design guidelines for co-rotating scroll improvement proposed. - Abstract: Efficient compressed air energy storage requires reversible isothermal compression and expansion devices. The isothermal compression and expansion processes can either be approached by several stages with intercooling or by the more convenient injection of a liquid, often water. While volumetric machines are readily available for dry processes the compression and expansion of a gas with the presence of liquid is still problematic. The concept of a co-rotating scroll has been identified as a promising technology to cope with the presence of liquid. The current paper discusses the first experimental results of an oil-free co-rotating scroll prototype tested in expansion mode on a wide range of rotational speeds, varying water injection flow rates and with different nominal flank clearances. A maximal overall isothermal efficiency of 34% and a maximum output power of 1.74 kW_e_l were measured with this first prototype, providing the proof of the technical feasibility of the oil-free co-rotating scroll expander concept. The experimental data indicate a positive effect of water injection suggesting good heat transfer behaviour between the water and the air in the individual chambers, which is a result of the relatively long residence time compared to other volumetric concepts. The experimental sensitivity analysis yields a strong dependency of the machine performance on both the nominal flank clearance and on the injected water rate. The analysis through a semi-empirical model suggests the inversion of a classical trend, i.e. the increase in total leakage area with

Development of the Simulation Program for the In-Vessel Fuel Handling System of Double Rotating Plug Type

International Nuclear Information System (INIS)

Kim, S. H.; Kim, J. B.

2011-01-01

In-vessel fuel handling machines are the main equipment of the in-vessel fuel handling system, which can move the core assembly inside the reactor vessel along with the rotating plug during refueling. The in vessel fuel handling machines for an advanced sodium cooled fast reactor(SFR) demonstration plant are composed of a direct lift machine(DM) and a fixed arm machine(FM). These machines should be able to access all areas above the reactor core by means of the rotating combination of double rotating plugs. Thus, in the in vessel fuel handling system of the double rotating plug type, it is necessary to decide the rotating plug size and evaluate the accessibility of in-vessel fuel handling machines in given core configuration. In this study, the simulation program based on LABVIEW which can effectively perform the arrangement design of the in vessel fuel handling system and simulate the rotating plug motion was developed. Fig. 1 shows the flow chart of the simulation program

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.

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

Biomass fueled closed cycle gas turbine with water injection

Energy Technology Data Exchange (ETDEWEB)

Bardi, Silvia [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Chemical Engineering and Technology

2001-01-01

Direct water injection has been studied for a small scale ({approx} 8 MW fuel input) closed cycle gas turbine coupled to a biomass fueled CFB furnace. Two different working fluids have been considered (helium-water mixture and nitrogen-water mixture). The water injection could take place between the compressor stages, as an intercooler, or after the high pressure compressor, as an aftercooler. Both this options have been studied, varying the relative humidity levels after the injection and the temperatures of the injected water. The effect of water injection on thermodynamic properties of the working fluids has been studied, together with its effect on turbomachinery isentropic efficiency. A sensitivity analysis on turbomachinery efficiency and cycle base pressure has been included. The results from this study have been compared to the performance of a dry closed cycle without water injection. The wet cycle shows an electric efficiency in the range 29-32% with helium-water mixture as working fluid and 30-32% with nitrogen-water mixture as working fluid, while the total efficiency (referring to the fuel LHV) is always higher than 100%. In the non-injected cycle the electric efficiency is 30-35% with helium and 32-36 with nitrogen. The total efficiency in the dry case with two level intercooling and postcooling is 87-89%, while is higher than 100% when only one stage inter- and postcooling is present. Aside from this, the study also includes a sizing of the heat exchangers for the different cycle variations. The heat transfer area is very sensible to the working fluid and to the amount of injected water and it's always higher when a nitrogen-water mixture is used. Compared to the cycle without water injection, by the way, the number of heat exchangers is reduced. This will lead to a lower pressure drop and a simpler plant layout. The total heat transfer area, however, is higher in the wet cycle than in the dry cycle.

Fuel injection and mixing systems having piezoelectric elements and methods of using the same

Science.gov (United States)

Mao, Chien-Pei [Clive, IA; Short, John [Norwalk, IA; Klemm, Jim [Des Moines, IA; Abbott, Royce [Des Moines, IA; Overman, Nick [West Des Moines, IA; Pack, Spencer [Urbandale, IA; Winebrenner, Audra [Des Moines, IA

2011-12-13

A fuel injection and mixing system is provided that is suitable for use with various types of fuel reformers. Preferably, the system includes a piezoelectric injector for delivering atomized fuel, a gas swirler, such as a steam swirler and/or an air swirler, a mixing chamber and a flow mixing device. The system utilizes ultrasonic vibrations to achieve fuel atomization. The fuel injection and mixing system can be used with a variety of fuel reformers and fuel cells, such as SOFC fuel cells.

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

Sensors Based Measurement Techniques of Fuel Injection and Ignition Characteristics of Diesel Sprays in DI Combustion System

Directory of Open Access Journals (Sweden)

S. Rehman

2016-09-01

Full Text Available Innovative sensor based measurement techniques like needle lift sensor, photo (optical sensor and piezoresistive pressure transmitter are introduced and used to measure the injection and combustion characteristics in direct injection combustion system. Present experimental study is carried out in the constant volume combustion chamber to study the ignition, combustion and injection characteristics of the solid cone diesel fuel sprays impinging on the hot surface. Hot surface ignition approach has been used to create variety of advanced combustion systems. In the present study, the hot surface temperatures were varied from 623 K to 723 K. The cylinder air pressures were 20, 30 and 40 bar and fuel injection pressures were 100, 200 and 300 bar. It is found that ignition delay of fuel sprays get reduced with the rise in injection pressure. The ignition characteristics of sprays much less affected at high fuel injection pressures and high surface temperatures. The fuel injection duration reduces with the increase in fuel injection pressures. The rate of heat release becomes high at high injection pressures and it decreases with the increase in injection duration. It is found that duration of burn/combustion decrease with the increase in injection pressure. The use of various sensors is quite effective, reliable and accurate in measuring the various fuel injection and combustion characteristics. The study simulates the effect of fuel injection system parameters on combustion performance in large heavy duty engines.

A Comparison of Fueling with Deuterium Pellet Injection from Different Locations on the DIII-D Tokamak

International Nuclear Information System (INIS)

Baylor, L.R.; Combs, S.K.; Gohil, P.; Houlberg, W.A.; Hsieh, C.; Jernigan, T.C.; Parks, P.B.

1999-01-01

Initial pellet injection experiments on DIII-D with high field side (HFS) injection have demonstrated that deeper pellet fuel deposition is possible even with HFS injected pellets that are significantly slower than pellets injected from the low field side (LFS) (outer midplane) location. A radial displacement of the pellet mass shortly after or during the ablation process is consistent with the observed mass deposition profiles measured shortly after injection. Vertical injection inside the magnetic axis shows some improvement in fueling efficiency over LFS injection and may provide an optimal injection location for fueling with high speed pellets

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)

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.

Efficacy of hyaluronic acid or steroid injections for the treatment of a rat model of rotator cuff injury.

Science.gov (United States)

Yamaguchi, Takeshi; Ochiai, Nobuyasu; Sasaki, Yu; Kijima, Takehiro; Hashimoto, Eiko; Sasaki, Yasuhito; Kenmoku, Tomonori; Yamazaki, Hironori; Miyagi, Masayuki; Ohtori, Seiji; Takahashi, Kazuhisa

2015-12-01

This study evaluated dorsal root ganglia from C3-C7, analyzed gait, and compared the expression of calcitonin gene-related peptide (CGRP) which was a marker of inflammatory pain in a rat rotator cuff tear model in which the supraspinatus and infraspinatus tendons were detached; comparisons were made to a sham group in which only the tendons were exposed. Fluorogold was injected into the glenohumeral joint 21 days after surgery in both groups, and saline, steroids, or hyaluronic acid was injected into the glenohumeral joint in the rotator cuff tear group 26 days after surgery. The proportions of CGRP-immunoreactive neurons were higher and the gait parameters were impaired in the rotator cuff tear group compared to in the sham group. However, the CGRP expression was reduced and the gait was improved with steroid or hyaluronic acid injection compared to saline, suggesting that both hyaluronic acid and steroid injections suppressed of inflammation which thought to be provided pain relief. While there were no significant differences, the suppression of CGRP expression and the improved gait after hyaluronic acid and steroid injections suggested that both methods were effective for rat rotator cuff tear model. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

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)

Fabrication of uranium alloy fuel slug for sodium-cooled fast reactor by injection casting

International Nuclear Information System (INIS)

Jong Hwan Kim; Hoon Song; Ki Hwan Kim; Chan Bock Lee

2014-01-01

Metal fuel slugs of U-Zr alloys for a sodium-cooled fast reactor (SFR) have been fabricated using an injection casting method. However, casting alloys containing volatile radioactive constituents such as Am can cause problems in a conventional injection casting method. Therefore, in this study, several injection-casting methods were applied to evaluate the volatility of the metal-fuel elements and control the transport of volatile elements. Mn was selected as a volatile surrogate alloy since it possesses a total vapor pressure equivalent to that of minor actinide-bearing fuels for SFRs. U-10 wt% Zr and U-10 wt% Zr-5 wt% Mn metal fuels were prepared, and the casting processes were evaluated. The casting soundness of the fuel slugs was characterized by gamma-ray radiography and immersion density measurements. Inductively coupled plasma atomic emission spectroscopy was used to determine the chemical composition of fuel slugs. Fuel losses after casting were also evaluated according to the casting conditions. (author)

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

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.

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%.

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)

Botulinum Toxin Injection for Internal Rotation Contractures in Brachial Plexus Birth Palsy. A Minimum 5-Year Prospective Observational Study.

Science.gov (United States)

Duijnisveld, Bouke J; van Wijlen-Hempel, Marie S; Hogendoorn, Simone; de Boer, Kees S; Malessy, Martijn J A; Keurentjes, J Christiaan; Nagels, Jochem; Nelissen, Rob G H H

Brachial plexus birth palsy is frequently associated with internal rotation contractures of the shoulder as a result of muscle imbalance. The purpose of this study is to assess the effect of botulinum toxin A (BTX-A) injection in the subscapular (SC) muscle on external rotation and the need for tendon transfer for external rotation of the shoulder. A prospective comparative study was performed including 15 consecutive patients treated with BTX-A and a historic control group of 67 patients with mean age 30 months (SD 10). The BTX-A injection (2 IU/kg body weight) was performed immediately following MRI under general anesthesia in the SC muscle. Passive external rotation, the need for tendon transfer surgery, glenohumeral deformity, and muscle degeneration were evaluated. The hazard ratio for no relapse of internal rotation contracture after BTX-A injection compared with no BTX-A injection was calculated. In the BTX-A group, the passive external rotation in adduction increased from -1 degree (95% CI, -10 to 8) to 32 degrees (95% CI, 17-46) at 3 months and 6 patients were indicated for surgery compared with a decline from -2 degrees (95% CI, -7 to 3) to -11 degrees (95% CI, -17 to -6) in the control group with 66 indications for surgery. At 5 years of follow-up, 10 patients in the BTX-A group were indicated for surgery with a hazard ratio of 4.0 (95% CI, 1.9 to 8.4). BTX-A injection in the SC muscle of brachial plexus birth palsy patients can reduce internal rotation contractures and subsequently the need for tendon transfer surgery. At 5 years of follow-up a relapse was seen in 67% of the patients treated with BTX-A. Because at MRI less SC degeneration was found in the good responders on BTX-A treatment, this group seems to be the best target group. Further research is needed on patient selection for BTX-A injection including glenohumeral deformity, SC degeneration, as well as doses of BTX-A to be used. Level II-prospective comparative study.

Specimen rotation system of the WSU TRIGA-fueled reactor

International Nuclear Information System (INIS)

Lovas, Thomas A.

1976-01-01

The specimen rotation system presently in use at the WSU reactor has been designed to provide maximum utilization of the irradiation capabilities achieved through use of TRIGA-type fuel. This paper describes the system with particular emphasis on characteristics which are advantageous to experimenters. (author)

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.

A study on the fuel injection and atomization characteristics of soybean oil methyl ester (SME)

International Nuclear Information System (INIS)

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

2009-01-01

The spray atomization characteristics of an undiluted biodiesel fuel (soybean oil methyl ester, SME) in a diesel engine were investigated and compared with that of diesel fuel (ultra low sulfur diesel, ULSD). The experimental results were compared with numerical results predicted by the KIVA-3V code. The spray characteristics of the spray tip penetration, spray area, spray centroid and injection delay were analyzed using images obtained from a visualization system. The Sauter mean diameter (SMD) was analyzed using a droplet analyzer system to investigate the atomization characteristics. It was found that the peak injection rate increases and advances when the injection pressure increases due to the increase of the initial injection momentum. The injection rate of the SME, which has a higher density than diesel fuel, is higher than that of diesel fuel despite its low injection velocity. The high ambient pressure induces the shortening of spray tip penetration of the SME. Moreover, the predicted spray tip penetration pattern is similar to the pattern observed experimentally. The SMD of the SME decreases along the axial distance. The predicted local and overall SMD distribution patterns of diesel and SME fuels illustrate similar tendencies when compared with the experimental droplet size distribution patterns

Analysis of Fuel Injection and Atomization of a Hybrid Air-Blast Atomizer.

Science.gov (United States)

Ma, Peter; Esclape, Lucas; Buschhagen, Timo; Naik, Sameer; Gore, Jay; Lucht, Robert; Ihme, Matthias

2015-11-01

Fuel injection and atomization are of direct importance to the design of injector systems in aviation gas turbine engines. Primary and secondary breakup processes have significant influence on the drop-size distribution, fuel deposition, and flame stabilization, thereby directly affecting fuel conversion, combustion stability, and emission formation. The lack of predictive modeling capabilities for the reliable characterization of primary and secondary breakup mechanisms is still one of the main issues in improving injector systems. In this study, an unstructured Volume-of-Fluid method was used in conjunction with a Lagrangian-spray framework to conduct high-fidelity simulations of the breakup and atomization processes in a realistic gas turbine hybrid air blast atomizer. Results for injection with JP-8 aviation fuel are presented and compared to available experimental data. Financial support through the FAA National Jet Fuel Combustion Program is gratefully acknowledged.

Fabrication of U-10wt.%Zr Fuel slug for SFR by Injection Casting

International Nuclear Information System (INIS)

Kim, Jong Hwan; Song, Hoon; Kim, Hyung Tae; Ko, Young Mo; Kim, Ki Hwan; Lee, Chan B.

2013-01-01

The fabrication technology of metal fuel has been developed by various methods such as rolling, swaging, wire drawing, and co-extrusion, but each of these methods had process limitations requiring an additional subsequent process, and needing the fabrication equipment is complex, which is not favorable for remote use. A practical process of metallic fuel fabrication for an SFR needs to be cost efficient, suitable for remote operation, and capable of mass production while reducing the amount of radioactive waste. Injection casting was chosen as the most promising technique, in the early 1950s, and this technique has been applied to fuel slug fabrication for the Experimental Breeder Reactor-II (EBR-II) driver and the Fast Flux Test Facility (FFTF) fuel pins. Because of the simplistic nature of the process and equipment, compared to other processes examined, this process has been successfully used in a remote operation environment for fueling of the EBR-II reactor. In this study, vacuum injection casting suitable for remote operation has been developed to fabricate metallic fuel for an SFR. Vacuum injection casting technique was developed to fabricate metallic fuel for an SFR. The appearance of the fabricated U-10wt.%Zr fuel was generally sound and the internal integrity was found to be satisfactory through gamma-ray radiography. Minimum fuel losses after casting relative to the initial charge amount of U-10wt.%Zr fuel slugs met the proposed goal of less than 0.1% fuel losses during fabrication. Modifications of the current facility system and advanced casting techniques are underway to produce higher quality fuel slugs

Fabrication of U-10wt.%Zr Fuel slug for SFR by Injection Casting

Energy Technology Data Exchange (ETDEWEB)

Kim, Jong Hwan; Song, Hoon; Kim, Hyung Tae; Ko, Young Mo; Kim, Ki Hwan; Lee, Chan B. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2013-10-15

The fabrication technology of metal fuel has been developed by various methods such as rolling, swaging, wire drawing, and co-extrusion, but each of these methods had process limitations requiring an additional subsequent process, and needing the fabrication equipment is complex, which is not favorable for remote use. A practical process of metallic fuel fabrication for an SFR needs to be cost efficient, suitable for remote operation, and capable of mass production while reducing the amount of radioactive waste. Injection casting was chosen as the most promising technique, in the early 1950s, and this technique has been applied to fuel slug fabrication for the Experimental Breeder Reactor-II (EBR-II) driver and the Fast Flux Test Facility (FFTF) fuel pins. Because of the simplistic nature of the process and equipment, compared to other processes examined, this process has been successfully used in a remote operation environment for fueling of the EBR-II reactor. In this study, vacuum injection casting suitable for remote operation has been developed to fabricate metallic fuel for an SFR. Vacuum injection casting technique was developed to fabricate metallic fuel for an SFR. The appearance of the fabricated U-10wt.%Zr fuel was generally sound and the internal integrity was found to be satisfactory through gamma-ray radiography. Minimum fuel losses after casting relative to the initial charge amount of U-10wt.%Zr fuel slugs met the proposed goal of less than 0.1% fuel losses during fabrication. Modifications of the current facility system and advanced casting techniques are underway to produce higher quality fuel slugs.

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.

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.)

Study of a fuel injection quantity sensor in diesel engine. Part 3. Experimental evaluation of the improved type micro turbine sensor; Diesel kikan ni okeru nenryo funsharyo sensor no kenkyu. 3. Funsharyo keisoku no seido kojo ni kansuru jikken hyoka

Energy Technology Data Exchange (ETDEWEB)

Maehara, H; Iwasaki, T; Kobayashi, T [Zexel Corp., Tokyo (Japan)

1997-10-01

A Micro Turbine Sensor has been developed to measure fuel injection quantity and injection rate. Previous reports described results of experiments on the MTS which were carried out under steady and unsteady flow conditions. The MTS has been improved in shape of a holder tip and a detecting procedure for rotating speed of a turbine. As a result revolution speed of the turbine increased 18% over the conventional type holder under steady flow condition. Furthermore the measurement resolution of the MTS came up to about 2(mm{sup 3}/pulse) at 20(mm{sup 3}/stroke) under intermittent spray conditions using fuel injection pump. 11 refs., 11 figs., 1 tab.

Relation Between Subacromial Bursitis on Ultrasonography and Efficacy of Subacromial Corticosteroid Injection in Rotator Cuff Disease: A Prospective Comparison Study.

Science.gov (United States)

Lee, Doo-Hyung; Hong, Ji Yeon; Lee, Michael Young; Kwack, Kyu-Sung; Yoon, Seung-Hyun

2017-05-01

To evaluate the correlations between subacromial bursitis (bursal thickening and effusion) on ultrasonography and its response to subacromial corticosteroid injection in patients with rotator cuff disease. Prospective, longitudinal comparison study. University-affiliated tertiary care hospital. Patients with rotator cuff disease (N=69) were classified into 3 groups based on ultrasonographic findings; (1) normative bursa group (group 1, n=23): bursa and effusion thickness 2mm and effusion thickness 2mm. A single subacromial injection with 20mg of triamcinolone acetonide. Visual analog scale (VAS) of shoulder pain, Shoulder Disability Questionnaire (SDQ), angles of active shoulder range of motion (flexion, abduction, external rotation, and internal rotation), and bursa and effusion thickness at pre- and posttreatment at week 8. There were no significant differences between the 3 groups in demographic characteristics pretreatment. Groups 2 and 3 showed a significant difference compared with group 1 in changes on the VAS and abduction; group 3 showed a significant difference compared with group 1 in changes of the SDQ, internal rotation, and external rotation; and all groups showed significant differences when compared with each other (groups 1 and 3, 2 and 3, and 1 and 2) in changes of thickness. A patient with ultrasonographic observation of subacromial bursitis, instead of normative bursa, can expect better outcome with subacromial corticosteroid injection. Therefore, we recommend a careful selection of patients using ultrasonography prior to injection. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

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.

Apparatus and method for controlling the secondary injection of fuel

Science.gov (United States)

Martin, Scott M.; Cai, Weidong; Harris, Jr., Arthur J.

2013-03-05

A combustor (28) for a gas turbine engine is provided comprising a primary combustion chamber (30) for combusting a first fuel to form a combustion flow stream (50) and a transition piece (32) located downstream from the primary combustion chamber (30). The transition piece (32) comprises a plurality of injectors (66) located around a circumference of the transition piece (32) for injecting a second fuel into the combustion flow stream (50). The injectors (66) are effective to create a radial temperature profile (74) at an exit (58) of the transition piece (32) having a reduced coefficient of variation relative to a radial temperature profile (64) at an inlet (54) of the transition piece (32). Methods for controlling the temperature profile of a secondary injection are also provided.

Superheated fuel injection for combustion of liquid-solid slurries

Science.gov (United States)

Robben, F.A.

1984-10-19

A method and device are claimed for obtaining, upon injection, flash evaporation of a liquid in a slurry fuel to aid in ignition and combustion. The device is particularly beneficial for use of coal-water slurry fuels in internal combustion engines such as diesel engines and gas turbines, and in external combustion devices such as boilers and furnaces. The slurry fuel is heated under pressure to near critical temperature in an injector accumulator, where the pressure is sufficiently high to prevent boiling. After injection into a combustion chamber, the water temperature will be well above boiling point at a reduced pressure in the combustion chamber, and flash boiling will preferentially take place at solid-liquid surfaces, resulting in the shattering of water droplets and the subsequent separation of the water from coal particles. This prevents the agglomeration of the coal particles during the subsequent ignition and combustion process, and reduces the energy required to evaporate the water and to heat the coal particles to ignition temperature. The overall effect will be to accelerate the ignition and combustion rates, and to reduce the size of the ash particles formed from the coal. 2 figs., 2 tabs.

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.

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.

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

A Study of Spill Control Characteristics of JP-8 and Conventional Diesel Fuel with a Common Rail Direct Injection System

Directory of Open Access Journals (Sweden)

Seomoon Yang

2017-12-01

Full Text Available Diversification of energy sources is a key task for decreasing environmental impacts and global emission of gases. JP-8, a fuel derived from natural gas, coal, biomass, and waste plastics, is a bright prospect. JP-8 is considered a multi-source multi-purpose fuel, with several applications. A preliminary characterization of the JP-8 injection rate and injection quantity behavior was investigated based on the high-pressure common rail injection system used in a heavy-duty engine. According to the spill injection and injection pressure, a trade-off trend between injection rate and injection quantity was observed. As expected, pilot injection of JP-8 aviation fuel and diesel fuel affects the spray quantity and injection evolution of the subsequent operation without pilot injection. The difference in spilling between diesel and JP-8 aviation fuel is greater than the difference in injection amount per time; in the process of controlling the injector solenoid through ECU (Electric Control Units, the oil pressure valve and the needle valve operate to a higher extent in order to maintain the diesel fuel’s injection quantity volume. It was found that the total injection quantity was decreased by adding 20% pilot injection duration. Because the pilot injection quantity causes solenoid response, loss and needle lift stroke friction loss.

Effects of injection nozzle exit width on rotating detonation engine

Science.gov (United States)

Sun, Jian; Zhou, Jin; Liu, Shijie; Lin, Zhiyong; Cai, Jianhua

2017-11-01

A series of numerical simulations of RDE modeling real injection nozzles with different exit widths are performed in this paper. The effects of nozzle exit width on chamber inlet state, plenum flowfield and detonation propagation are analyzed. The results are compared with that using an ideal injection model. Although the ideal injection model is a good approximation method to model RDE inlet, the two-dimensional effects of real nozzles are ignored in the ideal injection model so that some complicated phenomena such as the reflected waves caused by the nozzle walls and the reversed flow into the nozzles can not be modeled accurately. Additionally, the ideal injection model overpredicts the block ratio. In all the cases that stabilize at one-wave mode, the block ratio increases as the nozzle exit width gets smaller. The dual-wave mode case also has a relatively high block ratio. A pressure oscillation in the plenum with the same main frequency with the rotating detonation wave is observed. A parameter σ is applied to describe the non-uniformity in the plenum. σ increases as the nozzle exit width gets larger. Under some condition, the heat release on the interface of fresh premixed gas layer and detonation products can be strong enough to induce a new detonation wave. A spontaneous mode-transition process is observed for the smallest exit width case. Due to the detonation products existing in the premixed gas layer before the detonation wave, the detonation wave will propagate through reactants and products alternately, and therefore its strength will vary with time, especially near the chamber inlet. This tendency gets weaker as the injection nozzle exit width increases.

Exergo-Ecological Assessment Of Auxiliary Fuel Injection Into Blast-Furnace

Directory of Open Access Journals (Sweden)

Stanek W.

2015-06-01

Full Text Available Metallurgy represents complex technological chain supplied with different kinds of primary resources. Iron metallurgy based on blast-furnace process, dominates in world steel production. Metallurgical coke is the basic fuel in this case. Its production is connected with several environmental disadvantageous impacts. One of them is the extended production chain from primary energy to final energy. The reduction of coke consumption in the process can be achieved e.g. by injection of auxiliary fuels or increasing the thermal parameters in the process. In present injection of pulverised coal dominates while recirculation of top-gas seems to be future technology. However, the latter one requires the CO2 removal that additionally extended the production chain. The evaluation of resources management in complex energy-technological systems required application of advanced method based on thermodynamics. In the paper the system exergo-ecological assessment of pulverised coal injection into blast-furnace and top-gas recirculation has been applied. As a comparative criterion the thermo-ecological cost has been proposed.

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.

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))

Pulsed, supersonic fuel jets-A review of their characteristics and potential for fuel injection

International Nuclear Information System (INIS)

Milton, B.E.; Pianthong, K.

2005-01-01

High pressure fuel injection has provided considerable benefits for diesel engines, substantially reducing smoke levels while increasing efficiency. Current maximum pressures provide jets that are at less than the sonic velocity of the compressed air in the cylinders at injection. It has been postulated that a further increase into the supersonic range may benefit the combustion process due to increased aerodynamic atomization and the presence of jet bow shock waves that provide higher temperatures around the fuel. Pulsed, supersonic injection may also be beneficial for scramjet engines. The current program is examining pulsed, supersonic jets from a fundamental viewpoint both experimentally and numerically. Shock wave structures have been viewed for jets ranging from 600 to 2400 m/s, velocity attenuation and penetration distance measured, different nozzle designs examined and autoignition experiments carried out. Inside the nozzle, numerical simulation using the Autodyne code has been used to support an analytic approach while in the spray, the FLUENT code has been used. While benefits have not yet been defined, it appears that some earlier claims regarding autoignition at atmospheric conditions were optimistic but that increased evaporation and mixing are probable. The higher jet velocities are likely to mean that wall interactions are increased and hence matching such injectors to engine size and airflow patterns will be important

Current drive by neutral beams, rotating magnetic fields and helicity injection in compact toroids

International Nuclear Information System (INIS)

Farengo, R.; Arista, N.R.; Lifschitz, A.F.; Clemente, R.A.

2003-01-01

The use of neutral beams (NB) for current drive and heating in spheromaks, the relaxed states of flux core spheromaks (FCS) sustained by helicity injection and the effect of ion dynamics on rotating magnetic field (RMF) current drive in spherical tokamaks (ST) are studied. (author)

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...

Effect of water injection on nitric oxide emissions of a gas turbine combustor burning natural gas fuel

Science.gov (United States)

Marchionna, N. R.; Diehl, L. A.; Trout, A. M.

1973-01-01

The effect of direct water injection on the exhaust gas emissions of a turbojet combustor burning natural gas fuel was investigated. The results are compared with the results from similar tests using ASTM Jet-A fuel. Increasing water injection decreased the emissions of oxides of nitrogen (NOX) and increased the emissions of carbon monoxide and unburned hydrocarbons. The greatest percentage decrease in NOX with increasing water injection was at the lowest inlet-air temperature tested. The effect of increasing inlet-air temperature was to decrease the effect of the water injection. The reduction in NOX due to water injection was almost identical to the results obtained with Jet-A fuel. However, the emission indices of unburned hydrocarbons, carbon monoxide, and percentage nitric oxide in NOX were not.

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.

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.

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.

Cylinder Pressure-based Combustion Control with Multi-pulse Fuel Injection

NARCIS (Netherlands)

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

2015-01-01

With an increased number of fuel injection pulses, the control problem in diesel engines becomes complex. Consisting of multiple single-input single-output (SISO) controllers, the conventional control strategy shows unsatisfactory dynamic performance in tracking combustion load and phase reference

Modeling and control of plasma rotation for NSTX using neoclassical toroidal viscosity and neutral beam injection

Energy Technology Data Exchange (ETDEWEB)

Goumiri, I. R. [Princeton Univ., NJ (United States). Mechanical and Aerospace Dept.; Rowley, C. W. [Princeton Univ., NJ (United States). Mechanical and Aerospace Dept.; Sabbagh, S. A. [Columbia Univ., New York, NY (United States). Dept. of Applied Physics and Applied Mathematics; Gates, D. A. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Gerhardt, S. P. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Boyer, M. D. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Andre, R. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Kolemen, E. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Taira, K. [Florida State Univ, Dept Mech Engn, Tallahassee, FL USA.

2016-02-19

A model-based feedback system is presented to control plasma rotation in a magnetically confined toroidal fusion device, to maintain plasma stability for long-pulse operation. This research uses experimental measurements from the National Spherical Torus Experiment (NSTX) and is aimed at controlling plasma rotation using two different types of actuation: momentum from injected neutral beams and neoclassical toroidal viscosity generated by three-dimensional applied magnetic fields. Based on the data-driven model obtained, a feedback controller is designed, and predictive simulations using the TRANSP plasma transport code show that the controller is able to attain desired plasma rotation profiles given practical constraints on the actuators and the available measurements of rotation.

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

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

Entropy Generation in a Rotating Couette Flow with Suction/Injection

Directory of Open Access Journals (Sweden)

S. Das

2015-05-01

Full Text Available The present paper is concerned with an analytical study of entropy generation in viscous incompressible Couette flow with suction/injection in a rotating frame of reference. One of the plate is held at rest and the other one moves with an uniform velocity.The flow induced by the moving plate. An exact solution of governing equations has been obtained in closed form. The entropy generation number and the Bejan number are also obtained. The influences of each of the governing parameters on velocity, temperature, entropy generation and Bejan number are discussed with the help of graphs.

Apparatus and method for preventing the rotation of rods used in nuclear fuel assemblies

International Nuclear Information System (INIS)

Pilgrim, L.G. Jr.; Jackson, L.F.

1985-01-01

Apparatus and method for preventing the rotation of one or more elongated rods used in nuclear fuel assemblies include an end plug secured to one longitudinal end of such an elongated rod and having an out-of-cavity, non-round structure affixed thereto and configured to mate with a complementary shaped structure in a lower tie plate of a nuclear fuel assembly in such a manner as to prevent the rotation of the rod about its longitudinal axis. In one embodiment, the end plug includes a pair of flats formed on a portion of the end plug and configured to abut against a pair of flats formed on the outer surface of a cylindrical boss or sleeve of the lower tie plate, thereby to prevent the rotation of the rod. In another embodiment, four grooves, disposed 90 0 apart about the periphery of an end plug of a rod form a spline. The grooves are configured to receive four, radially inwardly protruding, key members disposed 90 0 apart about the periphery of a sleeve secured to the lower tie plate, thereby to prevent the rotation of the rod. In a further embodiment, a sleeve is secured to an end plug of a rod and includes four elongated slots disposed 90 0 apart about the periphery of the sleeve and configured in width, depth and spacing to receive and mate with four web portions of the lower tie plate of the nuclear fuel assembly, thereby to secure the rod against rotation about its longitudinal axis

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...

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.

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.

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.

Spray combustion of biomass-based renewable diesel fuel using multiple injection strategy in a constant volume combustion chamber

KAUST Repository

Jing, Wei

2016-05-26

Effect of a two-injection strategy associated with a pilot injection on the spray combustion process was investigated under conventional diesel combustion conditions (1000 K and 21% O2 concentration) for a biomass-based renewable diesel fuel, i.e., biomass to liquid (BTL), and a regular No. 2 diesel in a constant volume combustion chamber using multiband flame measurement and two-color pyrometry. The spray combustion flame structure was visualized by using multiband flame measurement to show features of soot formation, high temperature and low temperature reactions, which can be characterized by the narrow-band emissions of radicals or intermediate species such as OH, HCHO, and CH. The objective of this study was to identify the details of multiple injection combustion, including a pilot and a main injection, and to provide further insights on how the two injections interact. For comparison, three injection strategies were considered for both fuels including a two-injection strategy (Case TI), single injection strategy A (Case SA), and single injection strategy B (Case SB). Multiband flame results show a strong interaction, indicated by OH emissions between the pilot injection and the main injection for Case TI while very weak connection is found for the narrow-band emissions acquired through filters with centerlines of 430 nm and 470 nm. A faster flame development is found for the main injection of Case TI compared to Cases SA and SB, which could be due to the high temperature environment and large air entrainment from the pilot injection. A lower soot level is observed for the BTL flame compared to the diesel flame for all three injection types. Case TI has a lower soot level compared to Cases SA and SB for the BTL fuel, while the diesel fuel maintains a similar soot level among all three injection strategies. Soot temperature of Case TI is lower for both fuels, especially for diesel. Based on these results, it is expected that the two-injection strategy could be

Spray and atomization of diesel fuel and its alternatives from a single-hole injector using a common rail fuel injection system

KAUST Repository

Chen, PinChia

2013-01-01

Fuel spray and atomization characteristics play an important role in the performance of internal combustion engines. As the reserves of petroleum fuel are expected to be depleted within a few decades, finding alternative fuels that are economically viable and sustainable to replace the petroleum fuel has attracted much research attention. In this work, the spray and atomization characteristics were investigated for commercial No. 2 diesel fuel, biodiesel (FAME) derived from waste cooking oil (B100), 20% biodiesel blended diesel fuel (B20), renewable diesel fuel produced in house, and civil aircraft jet fuel (Jet-A). Droplet diameters and particle size distributions were measured by a laser diffraction particle analyzing system and the spray tip penetrations and cone angles were acquired using a high speed imaging technique. All experiments were conducted by employing a common-rail high-pressure fuel injection system with a single-hole nozzle under room temperature and pressure. The experimental results showed that biodiesel and jet fuel had different features compared with diesel. Longer spray tip penetration and larger droplet diameters were observed for B100. The smaller droplet size of the Jet-A were believed to be caused by its relatively lower viscosity and surface tension. B20 showed similar characteristics to diesel but with slightly larger droplet sizes and shorter tip penetration. Renewable diesel fuel showed closer droplet size and spray penetration to Jet-A with both smaller than diesel. As a result, optimizing the trade-off between spray volume and droplet size for different fuels remains a great challenge. However, high-pressure injection helps to optimize the trade-off of spray volume and droplet sizes. Furthermore, it was observed that the smallest droplets were within a region near the injector nozzle tip and grew larger along the axial and radial direction. The variation of droplet diameters became smaller with increasing injection pressure. �

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

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.

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

Experimental Study of Injection Characteristics of a Multi-hole port injector on various Fuel Injection pressures and Temperatures

Directory of Open Access Journals (Sweden)

Ommi F

2013-04-01

Full Text Available The structures of the port injector spray dominates the mixture preparation process and strongly affect the subsequent engine combustion characteristics over a wide range of operating conditions in port-injection gasoline engines. All these spray characteristics are determined by particular injector design and operating conditions. In this paper, an experimental study is made to characterize the breakup mechanism and spray characteristics of a injector with multi-disc nozzle (SAGEM,D2159MA. A comparison was made on injection characteristics of the multi-hole injectors and its effects on various fuel pressure and temperature. The distributions of the droplet size and velocity and volume flux were characterized using phase Doppler anemometry (PDA technique. Through this work, it was found that the injector produces a finer spray with a wide spray angle in higher fuel pressure and temperature.

Experimental Study of Injection Characteristics of a Multi-hole port injector on various Fuel Injection pressures and Temperatures

Science.gov (United States)

Movahednejad, E.; Ommi, F.; Nekofar, K.

2013-04-01

The structures of the port injector spray dominates the mixture preparation process and strongly affect the subsequent engine combustion characteristics over a wide range of operating conditions in port-injection gasoline engines. All these spray characteristics are determined by particular injector design and operating conditions. In this paper, an experimental study is made to characterize the breakup mechanism and spray characteristics of a injector with multi-disc nozzle (SAGEM,D2159MA). A comparison was made on injection characteristics of the multi-hole injectors and its effects on various fuel pressure and temperature. The distributions of the droplet size and velocity and volume flux were characterized using phase Doppler anemometry (PDA) technique. Through this work, it was found that the injector produces a finer spray with a wide spray angle in higher fuel pressure and temperature.

Developing the Model of Fuel Injection Process Efficiency Analysis for Injector for Diesel Engines

Science.gov (United States)

Anisimov, M. Yu; Kayukov, S. S.; Gorshkalev, A. A.; Belousov, A. V.; Gallyamov, R. E.; Lysenko, Yu D.

2018-01-01

The article proposes an assessment option for analysing the quality of fuel injection by the injector constituting the development of calculation blocks in a common injector model within LMS Imagine.Lab AMESim. The parameters of the injector model in the article correspond to the serial injector Common Rail-type with solenoid. The possibilities of this approach are demonstrated with providing the results using the example of modelling the modified injector. Following the research results, the advantages of the proposed approach to analysing assessing the fuel injection quality were detected.

Fuel consumption of gasoline ethanol blends at different engine rotational

Directory of Open Access Journals (Sweden)

Y. Barakat

2016-09-01

Full Text Available Fuel consumption (mf kg/h was estimated for two hydrocarbon gasolines (BG1-OE and BG2-OE and their ethanol blends which contain from 4 to 20 vol.% of ethanol. Fuel consumption experiments for sixteen fuel samples (5 L each, were conducted on a four cylinder, four stroke spark ignition test vehicle Sahin car, Type 1.45, model 2001. The engine has a swept volume of 1400 c.c., a compression ratio of 8.3:1 and a maximum power of 78 HP at 5500 rpm. The obtained data reveal that the relation between fuel consumption and ethanol concentration is linear. Six linear equations for BG1-ethanol blends and BG2-ethanol ones at the investigated rotational speeds, were developed. Fuel consumption values of the first set of gasoline-ethanol blends are lower than that of the second set. This may be attributed to the difference in the chemical composition of base gasolines BG1 in the first set which is enriched in the less volatile reformate if compared with the second set which is more enriched in isomerate, the more volatile refinery stream.

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

Investigation on the effects of pilot injection on low temperature combustion in high-speed diesel engine fueled with n-butanol–diesel blends

International Nuclear Information System (INIS)

Huang, Haozhong; Liu, Qingsheng; Yang, Ruzhi; Zhu, Tianru; Zhao, Ruiqing; Wang, Yaodong

2015-01-01

Highlights: • The effects of pre-injected timing and pre-injected mass were studied in CI engine. • The addition of n-butanol consumed OH free radicals, which delayed the ignition time. • With the increase of n-butanol, the BSFC and MPRR increased, NO_x and soot decreased. • With the advance of pilot injection timing, the BSFC increased, NO_x and soot decreased. • With the increase of pilot injection mass, NO_x increased, soot decreased then increased. - Abstract: The effect of pilot injection timing and pilot injection mass on combustion and emission characteristics under medium exhaust gas recirculation (EGR (25%)) condition were experimentally investigated in high-speed diesel engine. Diesel fuel (B0), two blends of butanol and diesel fuel denoted as B20 (20% butanol and 80% diesel in volume), and B30 (30% butanol and 70% diesel in volume) were tested. The results show that, for all fuels, when advancing the pilot injection timing, the peak value of heat release rate decreases for pre-injection fuel, but increases slightly for the main-injection fuel. Moreover, the in-cylinder pressure peak value reduces with the rise of maximum pressure rise rate (MPRR), while NO_x and soot emissions reduce. Increasing the pilot injection fuel mass, the peak value of heat release rate for pre-injected fuel increases, but for the main-injection, the peak descends, and the in-cylinder pressure peak value and NO_x emissions increase, while soot emission decreases at first and then increases. Blending n-butanol in diesel improves soot emissions. When pilot injection is adopted, the increase of n-butanol ratio causes the MPRR increasing and the crank angle location for 50% cumulative heat release (CA50) advancing, as well as NO_x and soot emissions decreasing. The simulation of the combustion of n-butanol–diesel fuel blends, which was based on the n-heptane–n-butanol–PAH–toluene mixing mechanism, demonstrated that the addition of n-butanol consumed OH free radicals

Theoretical study of the effects of pilot fuel quantity and its injection timing on the performance and emissions of a dual fuel diesel engine

International Nuclear Information System (INIS)

Papagiannakis, R.G.; Hountalas, D.T.; Rakopoulos, C.D.

2007-01-01

Various solutions have been proposed for improving the combustion process of conventional diesel engines and reducing the exhaust emissions without making serious modifications on the engine, one of which is the use of natural gas as a supplement for the conventional diesel fuel, the so called dual fuel natural gas diesel engines. The most common type of these is referred to as the pilot ignited natural gas diesel engine (PINGDE). Here, the primary fuel is natural gas that controls the engine power output, while the pilot diesel fuel injected near the end of the compression stroke auto-ignites and creates ignition sources for the surrounding gaseous fuel mixture to be burned. Previous research studies have shown that the main disadvantage of this dual fuel combustion is its negative impact on engine efficiency compared to the normal diesel operation, while carbon monoxide emissions are also increased. The pilot diesel fuel quantity and injection advance influence significantly the combustion mechanism. Then, in order to examine the effect of these two parameters on the performance and emissions, a comprehensive two-zone phenomenological model is employed and applied on a high-speed, pilot ignited, natural gas diesel engine located at the authors' laboratory. According to the results, the simultaneously increase of the pilot fuel quantity accompanied with an increase of its injection timing results to an improvement of the engine efficiency (increase) and of the emitted CO emissions (decrease) while it has a negative effect (increase) of NO emissions

Ducted fuel injection

Energy Technology Data Exchange (ETDEWEB)

Mueller, Charles J.

2018-03-06

Various technologies presented herein relate to enhancing mixing inside a combustion chamber to form one or more locally premixed mixtures comprising fuel and charge-gas with low peak fuel to charge-gas ratios to enable minimal, or no, generation of soot and other undesired emissions during ignition and subsequent combustion of the locally premixed mixtures. To enable sufficient mixing of the fuel and charge-gas, a jet of fuel can be directed to pass through a bore of a duct causing charge-gas to be drawn into the bore creating turbulence to mix the fuel and the drawn charge-gas. The duct can be located proximate to an opening in a tip of a fuel injector. The duct can comprise of one or more holes along its length to enable charge-gas to be drawn into the bore, and further, the duct can cool the fuel and/or charge-gas prior to combustion.

Neural control systems for alternatively fuelled vehicles and natural gas fuel injection for DACIA NOVA

Energy Technology Data Exchange (ETDEWEB)

Sulatisky, M. [Saskatchewan Research Council, Saskatoon, SK (Canada); Ghelesel, A. [BC Gas International, Vancouver, BC (Canada)

1999-07-01

The elements of natural gas vehicle conversion technology are described as background to a discussion of the development of bi-fuel injection system for the Rumanian-manufactured DACIA-NOVA automobile. The bi-fuel injection system mirrors the fueling system installed by the original equipment manufacturer; it can also be easily installed on Ford, General Motors and DaimlerChrysler vehicles as well as on most imports.To meet emission standards after 2000, it is envisaged to install on the DACIA NOVA a neural control system (NCS) and a completely adaptive linear control system (ACLS). Details of natural gas vehicles development and the development of NCS and ACLS are discussed, including short-term and long-term objectives.

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

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

The effect of water injection on nitric oxide emissions of a gas turbine combustor burning ASTM Jet-A fuel

Science.gov (United States)

Marchionna, N. R.; Diehl, L. A.; Trout, A. M.

1973-01-01

Tests were conducted to determine the effect of water injection on oxides of nitrogen (NOx) emissions of a full annular, ram induction gas turbine combustor burning ASTM Jet-A fuel. The combustor was operated at conditions simulating sea-level takeoff and cruise conditions. Water at ambient temperature was injected into the combustor primary zone at water-fuel ratios up to 2. At an inlet-air temperature of 589 K (600 F) water injection decreased the NOx emission index at a constant exponential rate: NOx = NOx (o) e to the -15 W/F power (where W/F is the water-fuel ratio and NOx(o) indicates the value with no injection). The effect of increasing combustor inlet-air temperature was to decrease the effect of the water injection. Other operating variables such as pressure and reference Mach number did not appear to significantly affect the percent reduction in NOx. Smoke emissions were found to decrease with increasing water injection.

Effect of cetane improver addition into diesel fuel: Methanol mixtures on performance and emissions at different injection pressures

Directory of Open Access Journals (Sweden)

Candan Feyyaz

2017-01-01

Full Text Available In this study, methanol in ratios of 5-10-15% were incorporated into diesel fuel with the aim of reducing harmful exhaust gasses of Diesel engine, di-tertbutyl peroxide as cetane improver in a ratio of 1% was added into mixture fuels in order to reduce negative effects of methanol on engine performance parameters, and isobutanol of a ratio of 1% was used as additive for preventing phase separation of all mixtures. As results of experiments conducted on a single cylinder and direct injection Diesel engine, methanol caused the increase of NOx emission while reducing CO, HC, CO2, and smoke opacity emissions. It also reduced torque and power values, and increased brake specific fuel consumption values. Cetane improver increased torque and power values slightly compared to methanol-mixed fuels, and reduced brake specific fuel consumption values. It also affected exhaust emission values positively, excluding smoke opacity. Increase of injector injection pressure affected performances of methanol-mixed fuels positively. It also increased injection pressure and NOx emissions, while reducing other exhaust emissions.

Numerical Investigation on Effects of Assigned EGR Stratification on a Heavy Duty Diesel Engine with Two-Stage Fuel Injection

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Zhaojie Shen

2018-02-01

Full Text Available External exhaust gas recirculation (EGR stratification in diesel engines contributes to reduction of toxic emissions. Weak EGR stratification lies in that strong turbulence and mixing between EGR and intake air by current introduction strategies of EGR. For understanding of ideal EGR stratification combustion, EGR was assigned radically at −30 °CA after top dead center (ATDC to organize strong EGR stratification using computational fluid dynamics (CFD. The effects of assigned EGR stratification on diesel performance and emissions are discussed in this paper. Although nitric oxides (NOx and soot emissions are both reduced by means of EGR stratification compared to uniform EGR, the trade-off between NOx and soot still exists under the condition of arranged EGR stratification with different fuel injection strategies. A deterioration of soot emissions was observed when the interval between main and post fuel injection increased, while NO emissions increased first then reduced. The case with a 4 °CA interval between main and post fuel injection is suitable for acceptable NO and soot emissions. Starting the main fuel injection too early and too late is not acceptable, which results in high NO emissions and high soot emissions respectively. The start of the main fuel injection −10 °CA ATDC is suitable.

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

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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.

Experimental investigation concerning the influence of fuel type and properties on the injection and atomization of liquid biofuels in an optical combustion chamber

International Nuclear Information System (INIS)

Galle, J.; Defruyt, S.; Van de Maele, C.; Rodriguez, R. Piloto; Denon, Q.; Verliefde, A.; Verhelst, S.

2013-01-01

Due to the scarcity of fossil fuels and the future stringent emission limits, there is an increasing interest for the use of renewable biofuels in compression ignition engines. However, these fuels have different physical, chemical and thermodynamic properties affecting atomization, spray development and combustion processes. The results reported in this paper have been obtained by experimentation with a constant volume combustion chamber. The influences of physical fuel properties on injections under non-evaporating conditions are studied, using a pump-line-nozzle system from a medium speed diesel engine with injection pressures up to 1200 bar, by changing the fuel type and temperature. Experiments were conducted for diesel, biodiesel, straight vegetable oils and animal fats. Injection pressure and needle lift measurements were analyzed. A high speed camera was used to visualize the spray, which enabled us to study the spray penetration and spray angle. Our results show that the fuel temperature is an important parameter to control because it significantly affects the fuel properties. Both the injection timing and injection duration are affected by the fuel properties. The influences of these properties on the spray development were less pronounced. At low temperatures, a strongly deteriorated atomization of oils and fats was observed. -- Highlights: • Spray measurements in an optical combustion chamber. • Influence on the injections system is compared for different bio-fuels. •Temperature effects the fuel properties, with strong influence on the injection system. • Viscosity has significant influence on atomization, especially for viscous fuels. • No difference for spray penetration and angle unlike the mass distribution

Evaluation of High Pressure Components of Fuel Injection Systems Using Speckle Interferometry

OpenAIRE

Basara, Adis

2007-01-01

The modern high pressure fuel injection systems installed in engines provide a highly efficient combustion process accompanied by low emissions of exhaust gases and an impressive level of dynamic response. The design and development of mechanical components for such systems pose a great challenge, since they have to operate under extremely high fluctuating pressures (e.g. up to 2000 bar) for a long lifetime (more than 1000 injections per minute). The permanent change between a higher and a lo...

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

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)

Does an Injection of Adipose-Derived Mesenchymal Stem Cells Loaded in Fibrin Glue Influence Rotator Cuff Repair Outcomes? A Clinical and Magnetic Resonance Imaging Study.

Science.gov (United States)

Kim, Yong Sang; Sung, Chang Hun; Chung, Sung Hoon; Kwak, Sang Joon; Koh, Yong Gon

2017-07-01

The mesenchymal stem cell (MSC)-based tissue engineering approach has been developed to improve the treatment of rotator cuff tears. Hypothesis/Purpose: The purpose was to determine the effect of an injection of adipose-derived MSCs loaded in fibrin glue during arthroscopic rotator cuff repair on clinical outcomes and to evaluate its effect on structural integrity using magnetic resonance imaging (MRI). The hypothesis was that the application of adipose-derived MSCs would improve outcomes after the surgical repair of a rotator cuff tear. Cohort study; Level of evidence, 3. Among 182 patients treated with arthroscopic surgery for a rotator cuff tear, 35 patients treated with arthroscopic rotator cuff repair alone (conventional group) were matched with 35 patients who underwent arthroscopic rotator cuff repair with an injection of adipose-derived MSCs loaded in fibrin glue (injection group) based on sex, age, and lesion size. Outcomes were assessed with respect to the visual analog scale (VAS) for pain, range of motion (ROM) (including forward flexion, external rotation at the side, and internal rotation at the back), and functional measures of the Constant score and University of California, Los Angeles (UCLA) shoulder rating scale. Repaired tendon structural integrity was assessed by using MRI at a minimum of 12 months after surgery, and the mean clinical follow-up was 28.8 ± 4.2 months in the conventional group and 28.3 ± 3.8 months in the injection group. The mean VAS score at rest and during motion improved significantly in both groups after surgery. However, there were no significant differences between the groups at the final follow-up ( P = .256 and .776, respectively). Compared with preoperative measurements, forward flexion and external rotation at the side significantly improved at the final follow-up in both groups (all P rotation at the back were observed in either group ( P = .625 and .834 for the conventional and injection groups, respectively

Mixing enhancement in a scramjet combustor using fuel jet injection swirl

Science.gov (United States)

Flesberg, Sonja M.

The scramjet engine has proven to be a viable means of powering a hypersonic vehicle, especially after successful flights of the X-51 WaveRider and various Hy-SHOT test vehicles. The major challenge associated with operating a scramjet engine is the short residence time of the fuel and oxidizer in the combustor. The fuel and oxidizer have only milliseconds to mix, ignite and combust in the combustion chamber. Combustion cannot occur until the fuel and oxidizer are mixed on a molecular level. Therefore the improvement of mixing is of utmost interest since this can increase combustion efficiency. This study investigated mixing enhancement of fuel and oxidizer within the combustion chamber of a scramjet by introducing swirl to the fuel jet. The investigation was accomplished with numerical simulations using STAR-CCM+ computational fluid dynamic software. The geometry of the University of Virginia Supersonic Combustion Facility was used to model the isolator, combustor and nozzle of a scramjet engine for simulation purposes. Experimental data from previous research at the facility was used to verify the simulation model before investigating the effect of fuel jet swirl on mixing. The model used coaxial fuel jet with a swirling annular jet. Single coaxial fuel jet and dual coaxial fuel jet configurations were simulated for the investigation. The coaxial fuel jets were modelled with a swirling annular jet and non-swirling core jet. Numerical analysis showed that fuel jet swirl not only increased mixing and entrainment of the fuel with the oxidizer but the mixing occurred further upstream than without fuel jet swirl. The burning efficiency was calculated for the all the configurations. An increase in burning efficiency indicated an increase in the mixing of H2 with O2. In the case of the single fuel jet models, the maximum burning efficiency increase due to fuel injection jet swirl was 23.3%. The research also investigated the possibility that interaction between two

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.

Bi-fuel System - Gasoline/LPG in A Used 4-Stroke Motorcycle - Fuel Injection Type

Science.gov (United States)

Suthisripok, Tongchit; Phusakol, Nachaphat; Sawetkittirut, Nuttapol

2017-10-01

Bi-fuel-Gasoline/LPG system has been effectively and efficiently used in gasoline vehicles with less pollutants emission. The motorcycle tested was a used Honda AirBlade i110 - fuel injection type. A 3-litre LPG storage tank, an electronic fuel control unit, a 1-mm LPG injector and a regulator were securely installed. The converted motorcycle can be started with either gasoline or LPG. The safety relief valve was set below 48 kPa and over 110 kPa. The motorcycle was tuned at the relative rich air-fuel ratio (λ) of 0.85-0.90 to attain the best power output. From dynamometer tests over the speed range of 65-100 km/h, the average power output when fuelling LPG was 5.16 hp; dropped 3.9% from the use of gasoline91. The average LPG consumption rate from the city road test at the average speed of 60 km/h was 40.1 km/l, about 17.7% more. This corresponded to lower LPG’s energy density of about 16.2%. In emission, the CO and HC concentrations were 44.4% and 26.5% lower. Once a standard gas equipment set with ECU and LPG injector were securely installed and the engine was properly tuned up to suit LPG’s characteristics, the converted bi-fuel motorcycle offers efficiently, safely and economically performance with environmental friendly emission.

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.

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.

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.

Nonlinear control of rotating stall and surge with axisymmetric bleed and air injection on axial flow compressors

Science.gov (United States)

Yeung, Chung-Hei (Simon)

The study of compressor instabilities in gas turbine engines has received much attention in recent years. In particular, rotating stall and surge are major causes of problems ranging from component stress and lifespan reduction to engine explosion. In this thesis, modeling and control of rotating stall and surge using bleed valve and air injection is studied and validated on a low speed, single stage, axial compressor at Caltech. Bleed valve control of stall is achieved only when the compressor characteristic is actuated, due to the fast growth rate of the stall cell compared to the rate limit of the valve. Furthermore, experimental results show that the actuator rate requirement for stall control is reduced by a factor of fourteen via compressor characteristic actuation. Analytical expressions based on low order models (2--3 states) and a high fidelity simulation (37 states) tool are developed to estimate the minimum rate requirement of a bleed valve for control of stall. A comparison of the tools to experiments show a good qualitative agreement, with increasing quantitative accuracy as the complexity of the underlying model increases. Air injection control of stall and surge is also investigated. Simultaneous control of stall and surge is achieved using axisymmetric air injection. Three cases with different injector back pressure are studied. Surge control via binary air injection is achieved in all three cases. Simultaneous stall and surge control is achieved for two of the cases, but is not achieved for the lowest authority case. This is consistent with previous results for control of stall with axisymmetric air injection without a plenum attached. Non-axisymmetric air injection control of stall and surge is also studied. Three existing control algorithms found in literature are modeled and analyzed. A three-state model is obtained for each algorithm. For two cases, conditions for linear stability and bifurcation criticality on control of rotating stall are

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

Structural investigation of the spinel phase formed in fuel CRUD before and after zinc injection

International Nuclear Information System (INIS)

Chen, J.

2002-01-01

Spinel phase is an important constituent of fuel CRUD. Since it can accommodate 60 Co in its crystal structure, its stability in reactor water environment is crucial for the radioactivity control in LWR plants. With increasing curiosity about zinc injection technology, the mechanism of the interaction of zinc with the spinel has drawn much attention. This paper describes the crystal and microstructures of spinel phase in the fuel CRUD collected on four fuel rods of 1- and 5-cycle, respectively, from Barsebaeck 2 BWR before and after zinc injection operation. High precision X-ray powder diffraction technique has been applied to identify the phase compositions of fuel CRUD and to measure the cell length of the spinel phase formed. The results show that, after about 1-cycle zinc injection operation, the tenacious CRUD formed on the fresh fuel rod contains defective zinc oxide, in addition to hematite and spinel as commonly seen. Moreover, the phase ratio of spinel to hematite is much increased. The cell length of the spinel is increased accordingly, which is the direct evidence for the presence of zinc in the spinel structure. For the 5-cycle rod, however, neither zinc oxide nor any change in the phase ratio has been detected. The cell length of the spinel has been increased, in a less degree, however, as compared to that for the 1-cycle rod. The cell lengths of spinel are similar in both tenacious and loose CRUD layers, indicating that zinc was able to easily penetrate through the tenacious CRUD layer. (authors)

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.

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.

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.

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

Impact of physical properties of biodiesel on the injection process in a common-rail direct injection system

International Nuclear Information System (INIS)

Boudy, Frederic; Seers, Patrice

2009-01-01

This paper presents the influence of biodiesel fuel properties on the injection mass flow rate of a diesel common-rail injection system. Simulations are first performed with ISO 4113 diesel fuel on a four-cylinder common-rail system to evaluate a single and triple injection strategies. For each injection strategy, the impact of modifying a single fuel property at a time is evaluated so as to quantify its influence on the injection process. The results show that fuel density is the main property that affects the injection process, such as total mass injected and pressure wave in the common-rail system. The fuel's viscosity and bulk modulus also influence, but to a lessen degree, the mass flow rate of the injector notably during multiple injection strategies as individual properties change the fuel's dampening property and friction coefficient.

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.

Improved fueling and transport barrier formation with pellet injection from different locations on DIII-D

International Nuclear Information System (INIS)

Baylor, L.R.; Jernigan, T.C.; Gohil, P.

2001-01-01

Pellet injection has been employed on DIII-D from different injection locations to optimize the mass deposition for density profile control and internal transport barrier formation. Transport barriers have been formed deep in the plasma core with central mass deposition from high field side (HFS) injected pellets and in the edge with pellets that trigger L-mode to H-mode transitions. Pellets injected from all locations can trigger the H-mode transition, which depends on the edge density gradient created and not on the radial extent of the pellet deposition. Pellets injected from inside the magnetic axis from the inner wall or vertical port lead to stronger central mass deposition than pellets injected from the low field side (LFS) and thus yield deeper more efficient fueling. (author)

Fuel assembly

International Nuclear Information System (INIS)

Fujibayashi, Toru.

1970-01-01

Herein disclosed is a fuel assembly in which a fuel rod bundle is easily detachable by rotating a fuel rod fastener rotatably mounted to the upper surface of an upper tie-plate supporting a fuel bundle therebelow. A locking portion at the leading end of each fuel rod protrudes through the upper tie-plate and is engaged with or separated from the tie-plate by the rotation of the fastener. The removal of a desired fuel rod can therefore be remotely accomplished without the necessity of handling pawls, locking washers and nuts. (Owens, K.J.)

Nuclear fuel pellet charging device

International Nuclear Information System (INIS)

Komuro, Kojiro.

1990-01-01

The present invention concerns a nuclear fuel pellet loading device, in which nuclear fuel pellets are successively charged from an open end of a fuel can while rotating the can. That is, a fuel can sealed at one end with an end plug and opened at the other end is rotated around its pipe axis as the center on a rotationally diriving table. During rotation of the fuel can, nuclear fuel pellets are successively charged by means of a feed rod of a feeding device to the inside of the fuel can. The fuel can is rotated while being supported horizontally and the fuel pellets are charged from the open end thereof. Alternatively, the fuel can is rotated while being supported obliquely and the fuel pellets are charged gravitationally into the fuel can. In this way, the damages to the barrier of the fuel can can be reduce. Further, since the fuel pellets can be charged gravitationally by rotating the fuel can while being supported obliquely, the damages to the barrier can be reduced remarkably. (I.S.)

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

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...

Fuel charging machine

International Nuclear Information System (INIS)

Uchikawa, Sadao.

1978-01-01

Purpose: To enable continuous fuel discharging and charging steps in a bwr type reactor by effecting positioning only for once by providing a plurality of fuel assembly grippers and their drives co-axially on a rotatable surface. Constitution: A plurality of fuel assembly grippers and their drives are provided co-axially on a rotatable surface. For example, a gripper A, a drive B, a gripper C and a drive D are arranged co-axially in symmetric positions on a disk rotated on rails by wheels and rotational drives. A new fuel in a fuel pool is gripped by the gripper A and transported above the reactor core. Then, the disk is positioned so that the gripper C can grip the spent fuel in the core, and the fuel to be discharged is gripped and raised by the gripper C. Then the disk is rotated by 180 0 and the new fuel in the gripper A is charged into the position from which the old fuel has been discharged and, finally, the discharged fuel is sent to the fuel pool for storage. (Seki, T.)

The Jet multipellet launcher and fueling of Jet plasmas by multipellet injection

International Nuclear Information System (INIS)

Kupschus, P.; Cheetham, A.; Denne, B.; Gadeberg, M.; Gowers, C.; Gondhalekar, A.; Tubbing, B.; Schmidt, G.L.; Colestock, P.; Hammett, G.; Zarnstorff, M.

1989-01-01

A multipellet long-pulse plasma fueling system, in operation on JET, is described. Plasma fueling experiments are performed with the 2.7 and 4.0 mm guns operating in the multipellet mode. The penetration of the pellets, which agrees with neutral and plasma shielding models, is shown. Details of particle deposition in ohmic plasmas and the plasma density evolution from far-infrared data, in response to pellet injection, are illustrated. A variety of plasma density profile shapes is produced with peak to average values ranging up to 2.5 and peak plasma density up to 1.2 X 10 20 /m 3

Spray combustion of biomass-based renewable diesel fuel using multiple injection strategy in a constant volume combustion chamber

KAUST Repository

Jing, Wei; Wu, Zengyang; Roberts, William L.; Fang, Tiegang

2016-01-01

Effect of a two-injection strategy associated with a pilot injection on the spray combustion process was investigated under conventional diesel combustion conditions (1000 K and 21% O2 concentration) for a biomass-based renewable diesel fuel, i

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.

Compact toroid injection fueling in a large field-reversed configuration

Science.gov (United States)

Asai, T.; Matsumoto, T.; Roche, T.; Allfrey, I.; Gota, H.; Sekiguchi, J.; Edo, T.; Garate, E.; Takahashi, Ts.; Binderbauer, M.; Tajima, T.

2017-07-01

A repetitively driven compact toroid (CT) injector has been developed for the large field-reversed configuration (FRC) facility of the C-2/C-2U, primarily for particle refueling. A CT is formed and injected by a magnetized coaxial plasma gun (MCPG) exclusively developed for the C-2/C-2U FRC. To refuel the particles of long-lived FRCs, multiple CT injections are required. Thus, a multi-stage discharge circuit was developed for a multi-pulsed CT injection. The drive frequency of this system can be adjusted up to 1 kHz and the number of CT shots per injector is two; the system can be further upgraded for a larger number of injection pulses. The developed MCPG can achieve a supersonic ejection velocity in the range of ~100 km s-1. The key plasma parameters of electron density, electron temperature and the number of particles are ~5  ×  1021 m-3, ~30 eV and 0.5-1.0  ×  1019, respectively. In this project, single- and double-pulsed counter CT injection fueling were conducted on the C-2/C-2U facility by two CT injectors. The CT injectors were mounted 1 m apart in the vicinity of the mid-plane. To avoid disruptive perturbation on the FRC, the CT injectors were operated at the lower limit of the particle inventory. The experiments demonstrated successful refueling with a significant density build-up of 20-30% of the FRC particle inventory per single CT injection without any deleterious effects on the C-2/C-2U FRC.

Influence of the pressure holding time on strain generation in fuel injection lines

International Nuclear Information System (INIS)

Basara, Adis; Alt, Nicolas; Schluecker, Eberhard

2011-01-01

An influence of the pressure holding time on residual strain generation during the autofrettage process was studied experimentally for the first time in the present work. It is the state of the art that fuel injection lines are held at the autofrettage pressure for only a few seconds in an industrial production. In doing so, it is assumed that a desirable residual stress-strain pattern is generated. However, the results of the experimental investigations outlined in this work indicated that completion of the plastic deformation caused by the autofrettage process and generation of the desirable stress-strain pattern require a much longer period. As shown, a third-order polynomial equation best described the interdependence between the time required for the completion of the process, the corresponding autofrettage pressure and the generated strain state. The method presented can be used as a tool for the determination of the optimal autofrettage process parameters in industrial production of fuel injection lines.

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.

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

Numerical Simulations of Hollow Cone Injection and Gasoline Compression Ignition Combustion With Naphtha Fuels

KAUST Repository

Badra, Jihad A.

2016-01-11

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 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 [1]. The feasibility of such a concept has been demonstrated by experimental investigations at Saudi Aramco [1, 2]. The present study aims to develop predictive capabilities for low octane gasoline fuel compression ignition 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 tested and compared with the experimental data. An optimum combination has been identified and applied in the combusting GCI simulations. Linear instability sheet atomization (LISA) breakup model and modified Kelvin-Helmholtz and Rayleigh-Taylor (KH-RT) break models proved to work the best for the investigated injector. Comparisons between various existing spray models and a parametric study have been carried out to study the effects of various spray parameters. The fuel effects have been tested by using three different primary reference fuel (PRF

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

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.

Benchmarking Pt-based electrocatalysts for low temperature fuel cell reactions with the rotating disk electrode

DEFF Research Database (Denmark)

Pedersen, Christoffer Mølleskov; Escribano, Maria Escudero; Velazquez-Palenzuela, Amado Andres

2015-01-01

We present up-to-date benchmarking methods for testing electrocatalysts for polymer exchange membrane fuel cells (PEMFC), using the rotating disk electrode (RDE) method. We focus on the oxygen reduction reaction (ORR) and the hydrogen oxidation reaction (HOR) in the presence of CO. We have chosen...

Short rotation coppice as a fuel: framework for a contractual infrastructure

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-07-01

This report summarises the results of a study exploring the contractual interface between growers and suppliers of short rotation coppice fuels and power generators in England and Wales, France and Sweden. Reviews of the main contractual considerations in relation to growers and generators in the UK, and Swedish and UK studies are presented. Proposals for the contractual treatment in the UK of the issues raised by the studies are considered, and recommendations for the treatment of contractual and economic requirements prevailing in France and Sweden are given. Appendices contains model agreements. (UK)

Decreasing the emissions of a partially premixed gasoline fueled compression ignition engine by means of injection characteristics and EGR

Directory of Open Access Journals (Sweden)

Nemati Arash

2011-01-01

Full Text Available This paper is presented in order to elucidate some numerical investigations related to a partially premixed gasoline fuelled engine by means of three dimensional CFD code. Comparing with the diesel fuel, gasoline has lower soot emission because of its higher ignition delay. The application of double injection strategy reduces the maximum heat release rate and leads to the reduction of NOx emission. For validation of the model, the results for the mean in-cylinder pressure, H.R.R., NOx and soot emissions are compared with the corresponding experimental data and show good levels of agreement. The effects of injection characteristics such as, injection duration, spray angle, nozzle hole diameter, injected fuel temperature and EGR rate on combustion process and emission formation are investigated yielding the determination of the optimal point thereafter. The results indicated that optimization of injection characteristics leads to simultaneous reduction of NOx and soot emissions with negligible change in IMEP.

Numerical investigation on the effect of injection pressure on the internal flow characteristics for diethyl ether, dimethyl ether and diesel fuel injectors using CFD

Directory of Open Access Journals (Sweden)

Vijayakumar Thulasi

2011-01-01

Full Text Available The spray characteristics of the diesel fuel are greatly affected by the cavitation formed inside the injector due to the high pressure differential across the nozzle. Many researchers across the globe are exploring the potential of using diethyl ether and dimethyl ether as an alternate for diesel fuel to meet the strict emission norms. Due to the variation in the fuel properties the internal flow characteristics in injectors for ether fuels are expected to be different from that of the diesel fuel. In this paper computational technique is used to study and compare the internal flow characteristics of diethyl ether, dimethyl ether and diesel fuel. The two phase flow model considering the fuel as a mixture of liquid and vapor is adopted for the simulation study. The injection pressure is varied from 100 to 400 bar and the flow characteristics of all three fuels are simulated and compared. Results indicate that all three fuels have distinct cavitating patterns owing to different property values. The dimethyl ether is found to be more cavitating than diesel and diethyl ether fuels as expected. The mass of fuel injected are found to be decreasing for the ether fuels when compared with diesel fuel at all injection pressures.

Ultrasound guided versus landmark guided corticosteroid injection in patients with rotator cuff syndrome: Randomised controlled trial.

Science.gov (United States)

Bhayana, Himanshu; Mishra, Puneet; Tandon, Anupama; Pankaj, Amite; Pandey, Rohit; Malhotra, Raskesh

2018-03-01

Impingement syndrome is the most common differential in a patient presenting to an orthopaedic OPD with shoulder pain. Impingement syndrome is often managed with subacromial corticosteroid injection, which can be instilled using either landmark guided (LMG) approach or with the assistance of ultrasound (US). This study was envisaged to enquire whether ultrasound assistance improves the accuracy, efficacy or safety profile of the injection. 60 patients of rotator cuff syndrome underwent diagnostic ultrasound. They were randomly assigned to receive subacromial injection of 2 ml (40 mg/ml) methylprenisolone and 2 ml of 1% lignocaine combination either by US assistance (n = 30) or using LMG assistance (n = 30). The patients were evaluated before injection and on follow up visits at day 5, week 3, week 6 and 3rd month by a single assessor. The assessor was blinded of the treatment group to which patient belonged. Clinical assessment included demographic and clinical data, accuracy of injection, VAS (0-100) for pain, Constant score with goniometer evaluation of range of motion, patient's self assessment proforma and post injection side effects if any. Initial demographic, clinical and US findings in the groups exhibited no significant differences. The accuracy of US guided injections (100%) was more when compared from LMG injection (93.3%). Both VAS and Constant score showed significant improvement following steroid injection up to 3 months of follow up. However the differences in the two groups were not significant suggesting comparable efficacy of the two approaches. (Mean VAS score decrease: 27.23 for US and 25.16 for LMG, p guided injections have a higher accuracy of drug placement in the subacromial bursa, there is no difference in terms of clinical outcomes or safety profile of either of the method. Hence US guided injections seems to be unjustified, when compared to equally efficacious and cost effective LMG steroid injection.

Effect of zinc injection on BWR fuel cladding corrosion. Pt. 1. Study on an accelerated corrosion condition to evaluate corrosion resistance of zircaloy-2 fuel cladding

International Nuclear Information System (INIS)

Kawamura, Hirotaka; Kanbe, Hiromu; Furuya, Masahiro

2002-01-01

Japanese BWR utilities have a plan to apply zinc injection to the primary coolant in order to reduce radioactivity accumulation on the structure. Prior to applying the zinc injection to BWR plants, it is necessary to evaluate the effect of zinc injection on corrosion resistance of fuel cladding. The objective of this report was to examine the accelerated corrosion condition for evaluation of BWR fuel cladding corrosion resistance under non-irradiated conditions, as the first step of a zinc injection evaluation study. A heat transfer corrosion test facility, in which a two phase flow condition could be achieved, was designed and constructed. The effects of heat flux, void fraction and solution temperature on BWR fuel cladding corrosion resistance were quantitatively investigated. The main findings were as follows. (1) In situ measurements using high speed camera and a void sensor together with one dimensional two phase flow analysis results showed that a two phase flow simulated BWR core condition can be obtained in the corrosion test facility. (2) The heat transfer corrosion test results showed that the thickness of the zirconium oxide layer increased with increasing solution temperature and was independent of heat flux and void fraction. The corrosion accelerating factor was about 2.5 times in the case of a temperature increase from 288degC to 350degC. (author)

Electrically controlled fuel injection system for an internal combustion engine with a control multi-vibrator and electrical correction of the voltage. Elektrisch gesteuerte Kraftstoffeinspritzanlage fuer eine Brennkraftmaschine mit einem Steuermultivibrator und elektrischer Spannungskorrektur

Energy Technology Data Exchange (ETDEWEB)

Busse, W; Drews, U; Moeder, H; Ohr, K; Werner, P

1980-06-19

The invention concerns an electrically controlled fuel injection system for an internal combustion engine with at least one solenoid operated injection valve and a power transistor in series with the magnetising winding of the valve and with a control multi-vibrator connected before this, which is switched on synchronously with the crankshaft rotation with simultaneous opening of the injection valve, and which is kept in this state for a period determining the quantity injected, depending on the quantity of suction air. A control pulse is supplied for at least one injection valve, which is extended by a voltage correction stage proportionally to the voltage of a source of electrical supply provided for operating the injection valve, particularly to a vehicle battery. It has been found that the delay in response of the solenoid injection valves is independent of the duration of the opening pulse and must be compensated by an additional fuse independent of the length of the opening pulse, whose duration increases with increasing voltage drop. According to the invention this is achieved by a voltage-correcting stage with a Zener diode and several transistors. The individual operating steps are made clear by 3 patent claims and several detailed circuit diagrams and pulse-time graphs.

Method and means for repairing injection fuel pump pistons

Energy Technology Data Exchange (ETDEWEB)

Ash, E.G.; Tompkins, M.J. Jr.

1988-06-07

This patent describes an improvement in timing pistons for rotary fuel injection pumps of the type having a die cast aluminum housing. The housing has a cylindrical chamber, a steel piston, the piston being received in the chamber, means for reciprocating the piston lengthwise of the chamber, an aluminum jacket surrounding the piston and extending the full length thereof, the jacket being rigidly secured to the piston. The jacket has an exterior surface hard coat anodized to the hardness of about 60-70 Rockwell (C scale) as the means of preventing galling due to the reciprocal movement of the aluminum jacket piston within the aluminum chamber.

Worldwide Injection Technique Questionnaire Study: Injecting Complications and the Role of the Professional.

Science.gov (United States)

Frid, Anders H; Hirsch, Laurence J; Menchior, Astrid R; Morel, Didier R; Strauss, Kenneth W

2016-09-01

From February 1, 2014, through June 30, 2015, 13,289 insulin-injecting patients from 423 centers in 42 countries participated in one of the largest surveys ever performed in diabetes. The first results of this survey are published elsewhere in this issue. Herein we report that the most common complication of injecting insulin is lipohypertrophy (LH), which was self-reported by 29.0% of patients and found by physical examination in 30.8% by health care professionals (HCPs). Patients with LH consumed a mean of 10.1 IU more insulin daily than patients without LH. Glycated hemoglobin levels averaged 0.55% higher in patients with vs without LH. Lipohypertrophy was associated with higher rates of unexplained hypoglycemia and glycemic variability as well as more frequent diabetic ketoacidosis, incorrect rotation of injection sites, use of smaller injection zones, longer duration of insulin use, and reuse of pen needles (each P<.05). Routine inspection of injection sites by the HCP was associated with lower glycated hemoglobin levels, less LH, and more correct injection site rotation. Patients were also more likely to rotate correctly if they received injection instructions from their HCP in the past 6 months. Fewer than 40% of patients claimed to have gotten such instructions in the past 6 months, and 10% said that they have never received training on how to inject correctly despite injecting for a mean of nearly 9 years. Use of these data should stimulate renewed commitment to optimizing insulin injection practices. Copyright © 2016 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

Effect of Fuel Injection and Mixing Characteristics on Pulse-Combustor Performance at High-Pressure

Science.gov (United States)

Yungster, Shaye; Paxson, Daniel E.; Perkins, Hugh D.

2014-01-01

Recent calculations of pulse-combustors operating at high-pressure conditions produced pressure gains significantly lower than those observed experimentally and computationally at atmospheric conditions. The factors limiting the pressure-gain at high-pressure conditions are identified, and the effects of fuel injection and air mixing characteristics on performance are investigated. New pulse-combustor configurations were developed, and the results show that by suitable changes to the combustor geometry, fuel injection scheme and valve dynamics the performance of the pulse-combustor operating at high-pressure conditions can be increased to levels comparable to those observed at atmospheric conditions. In addition, the new configurations can significantly reduce the levels of NOx emissions. One particular configuration resulted in extremely low levels of NO, producing an emission index much less than one, although at a lower pressure-gain. Calculations at representative cruise conditions demonstrated that pulse-combustors can achieve a high level of performance at such conditions.

Anomalous Ion Heating, Intrinsic and Induced Rotation in the Pegasus Toroidal Experiment

Science.gov (United States)

Burke, M. G.; Barr, J. L.; Bongard, M. W.; Fonck, R. J.; Hinson, E. T.; Perry, J. M.; Redd, A. J.; Thome, K. E.

2014-10-01

Pegasus plasmas are initiated through either standard, MHD stable, inductive current drive or non-solenoidal local helicity injection (LHI) current drive with strong reconnection activity, providing a rich environment to study ion dynamics. During LHI discharges, a large amount of anomalous impurity ion heating has been observed, with Ti ~ 800 eV but Te < 100 eV. The ion heating is hypothesized to be a result of large-scale magnetic reconnection activity, as the amount of heating scales with increasing fluctuation amplitude of the dominant, edge localized, n = 1 MHD mode. Chordal Ti spatial profiles indicate centrally peaked temperatures, suggesting a region of good confinement near the plasma core surrounded by a stochastic region. LHI plasmas are observed to rotate, perhaps due to an inward radial current generated by the stochastization of the plasma edge by the injected current streams. H-mode plasmas are initiated using a combination of high-field side fueling and Ohmic current drive. This regime shows a significant increase in rotation shear compared to L-mode plasmas. In addition, these plasmas have been observed to rotate in the counter-Ip direction without any external momentum sources. The intrinsic rotation direction is consistent with predictions from the saturated Ohmic confinement regime. Work supported by US DOE Grant DE-FG02-96ER54375.

Flow visualization studies of transverse fuel injection patterns in a nonreacting Mach 2 combustor

Science.gov (United States)

Mcdaniel, J. C.

1987-01-01

Planar visualization images are recorded of transverse jet mixing in a supersonic combustor flowfield, without chemical reaction, using laser-induced fluorescence from iodine molecules. Digital image processing and three-dimensional display enable complete representations of fuel penetration boundary and shock surfaces corresponding to several injection geometries and pressures.

A laser-induced-fluorescence visualization study of transverse, sonic fuel injection in a nonreacting supersonic combustor

Science.gov (United States)

Mcdaniel, J. C.; Graves, J., Jr.

1986-01-01

The present paper reports work which has been conducted in the first phase of a research program which is to provide a data base of spatially-resolved measurements in nonreacting supersonic combustors. In the measurements, a nonintrusive diagnostic technique based on the utilization of laser-induced fluorescence (LIF) is employed. The reported work had the objective to conduct LIF visualization studies of the injection of a simulated fuel into a Mach 2.07 airstream for comparison with corresponding numerical calculations. Attention is given to injection from a single orifice into a constant-area duct, injection from a single orifice behind a rearward-facing step, and injection from staged orifices behind a rearward-facing step.

X-ray vision of fuel sprays

International Nuclear Information System (INIS)

Wang, J.

2005-01-01

With brilliant synchrotron X-ray sources, microsecond time-resolved synchrotron X-ray radiography and tomography have been used to elucidate the detailed three-dimensional structure and dynamics of high-pressure high-speed fuel sprays in the near-nozzle region. The measurement allows quantitative determination of the fuel distribution in the optically impenetrable region owing to the multiple scattering of visible light by small atomized fuel droplets surrounding the jet. X-radiographs of the jet-induced shock waves prove that the fuel jets become supersonic under appropriate injection conditions and that the quantitative analysis of the thermodynamic properties of the shock waves can also be derived from the most direct measurement. In other situations where extremely axial-asymmetric sprays are encountered, mass deconvolution and cross-sectional fuel distribution models can be computed based on the monochromatic and time-resolved X-radiographic images collected from various rotational orientations of the sprays. Such quantitative analysis reveals the never-before-reported characteristics and most detailed near-nozzle mass distribution of highly transient fuel sprays

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.)

CNG INJECTOR RESEARCH FOR DUAL FUEL ENGINE

Directory of Open Access Journals (Sweden)

Adam Majczak

2017-03-01

Full Text Available The article presents the tests results of the prototype design of hydraulically assisted injector, that is designed for gas supply into diesel engines. The construction of the injector allows for it positioning in the glow plug socket, so that the gas is injected directly into the combustion chamber. The cycle analysis of the four-cylinder Andoria ADCR engine with a capacity of 2.6 dm3 for different crankshaft rotational speeds allowed to determine the necessary time for fuel injection. Because of that, it was possible to determine the required mass flow rate of the injector, for replacing as much of the original fuel by gaseous fuel. To ensure a high value of flow inside the injector, supply pressure equal to 1 MPa was applied. High gas supply pressure requires high value of valve opening forces. For this purpose a injector with hydraulic control system, using a liquid under pressure for the opening process was designed. On the basis of air pressure measurements in the flow line after the injector, the analysis of opening and closing of the valve was made. Measurements of outflow mass of the injector were also carried out. The results showed that the designed injector meets the requirements necessary to supply ADCR engine by the CNG fuel.

Injection of heavy fuel oil into the blast furnace

Energy Technology Data Exchange (ETDEWEB)

Paloposki, T. [Helsinki Univ. of Technology, Otaniemi (Finland); Hakala, J.; Mannila, P.; Laukkanen, J. [Oulu Univ. (Finland)

1996-12-31

This study deals with the injection and combustion of heavy fuel oil in blast furnaces. The injection of the oil was studied experimentally in a small-scale test rig. The combustion of the oil was analysed with a commercial computer program for flow and combustion simulations. Results from computer simulations show that the combustion of the oil can be improved by decreasing the size of the oil drops and by enhancing the mixing between the oil drops and the hot blast. The devolatilization rate of the oil mainly depends on the size of the oil drops. The combustion rate of the volatiles mainly depends on the effectiveness of turbulent mixing with combustion air. Methods to decrease the size of the oil drops were sought in the experimental part of the study. Experimental results show that the size of the oil drops increases with increasing mass flow rate of the oil and decreases with increasing velocity of the hot blast. Methods to improve the mixing between the oil drops and the hot blast are suggested but have not yet been experimentally tested. (author) (4 refs.)

Injection of heavy fuel oil into the blast furnace

Energy Technology Data Exchange (ETDEWEB)

Paloposki, T [Helsinki Univ. of Technology, Otaniemi (Finland); Hakala, J; Mannila, P; Laukkanen, J [Oulu Univ. (Finland)

1997-12-31

This study deals with the injection and combustion of heavy fuel oil in blast furnaces. The injection of the oil was studied experimentally in a small-scale test rig. The combustion of the oil was analysed with a commercial computer program for flow and combustion simulations. Results from computer simulations show that the combustion of the oil can be improved by decreasing the size of the oil drops and by enhancing the mixing between the oil drops and the hot blast. The devolatilization rate of the oil mainly depends on the size of the oil drops. The combustion rate of the volatiles mainly depends on the effectiveness of turbulent mixing with combustion air. Methods to decrease the size of the oil drops were sought in the experimental part of the study. Experimental results show that the size of the oil drops increases with increasing mass flow rate of the oil and decreases with increasing velocity of the hot blast. Methods to improve the mixing between the oil drops and the hot blast are suggested but have not yet been experimentally tested. (author) (4 refs.)

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.

Effect of two-stage injection on combustion and emissions under high EGR rate on a diesel engine by fueling blends of diesel/gasoline, diesel/n-butanol, diesel/gasoline/n-butanol and pure diesel

International Nuclear Information System (INIS)

Zheng, Zunqing; Yue, Lang; Liu, Haifeng; Zhu, Yuxuan; Zhong, Xiaofan; Yao, Mingfa

2015-01-01

Highlights: • Two-stage injection using diesel blended fuel at high EGR (46%) was studied. • Blending fuels induce retarded pilot heat release and have less effect on MPRR. • Effects of injection parameters of blended fuels on emissions are similar to diesel. • Different fuels have little influence on post combustion heat release. • Small quantity post injection close to main results in better efficiency and emissions. - Abstract: The effect of two-stage injection on combustion and emission characteristics under high EGR (46%) condition were experimentally investigated. Four different fuels including pure diesel and blended fuels of diesel/gasoline, diesel/n-butanol, diesel/gasoline/n-butanol were tested. Results show that blending gasoline or/and n-butanol in diesel improves smoke emissions while induces increase in maximum pressure rise rate (MPRR). Adopting pilot injection close to main injection can effectively reduce the peak of premixed heat release rate and MPRR. However, for fuels blends with high percentage of low cetane number fuel, the effect of pilot fuel on ignition can be neglected and the improvement of MPRR is not that obvious. Pilot-main interval presents more obvious effect on smoke than pilot injection rate does, and the smoke emissions decrease with increasing pilot-main interval. A longer main-post interval results in a lower post heat release rate and prolonged combustion duration. While post injection rate has little effect on the start of ignition for post injection. The variation in fuel properties caused by blending gasoline or/and n-butanol into diesel does not impose obvious influence on post combustion. The smoke emission increases first and then declines with retard of post injection timing. Compared to diesel, the smoke emissions of blended fuels are more sensitive to the variation of post injection strategy

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.

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.

Investigation of the spray characteristics for a secondary fuel injection nozzle using a digital image processing method

Science.gov (United States)

Jeong, Haeyoung; Lee, Kihyung; Ikeda, Yuji

2007-05-01

There are many ways to reduce diesel engine exhaust emissions. However, NOx emission is difficult to reduce because the hydrocarbon (HC) concentration in a diesel engine is not sufficient for NOx conversion. Therefore, in order to create stoichiometric conditions in the De-NOx catalyst, a secondary injection system is designed to inject liquid HC into the exhaust pipe. The atomization and distribution characteristics of the HC injected from a secondary injector are key technologies to obtain a high NOx conversion because inhomogeneous droplets of injected HC cause not only high fuel consumption but also deterioration of NOx emission. This paper describes the spray characteristics of a secondary injector including the spray angle, penetration length and breakup behaviour of the spray to optimize the reduction rate of the NOx catalyst. In this study, various optical diagnostics were applied to investigate these spray characteristics, the atomization mechanism and spray developing process. The visualization and image processing method for the spray pulsation were developed by high speed photography. The influence of the fuel supply pressure on the spray behaviour and a more detailed spray developing process have been analysed experimentally using image processing. Finally, the experimental results were used to correlate the spray structure to the injection system performance and to provide a design guide for a secondary injector nozzle.

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

Synchronized droplet size measurements for Coal-Water-Slurry (CWS) diesel sprays of an electronically-controlled fuel injection system

Science.gov (United States)

Kihm, K. D.; Terracina, D. P.; Payne, S. E.; Caton, J. A.

Experiments were completed to study intermittent coal-water slurry (CWS) fuel sprays injected from an electronically-controlled accumulator injector system. A laser diffraction particle analyzing (LDPA) technique was used to measure the spray diameters (Sauter mean diameter, SMD) assuming the Rosin-Rammler two parameter model. In order to ensure an accurate synchronization of the measurement with the intermittent sprays, a new synchronization technique was developed using the light extinction signal as a triggering source for the data taking initiation. This technique allowed measurement of SMD's near the spray tip where the light extinction was low and the data were free from the multiscattering bias. Coal-water slurry fuel with 50% coal loading in mass containing 5 (mu)m mass median diameter coal particulates was considered. Injection pressures ranging from 28 to 110 MPa, two different nozzle orifice diameters, 0.2 ad 0.4 mm, and four axial measurement locations from 60 to 120 mm from the nozzle orifice were studied. Measurements were made for pressurized (2.0 MPa in gauge) and for ambient chamber conditions. The spray SMD showed an increase with the distance of the axial measurement location and with the ambient gas density, and showed a decrease with increasing injection pressure. A correlation of the Sauter mean diameter with the injection conditions was determined. The results were also compared with previous SMD correlations that were available only for diesel fuel sprays.

Feedback controlled fuel injection system can accommodate any alcohol-gasoline blend

Energy Technology Data Exchange (ETDEWEB)

Pefley, R K; Pullman, J B; Suga, T P; Espinola, S

1980-01-01

A fuel metering system has been adapted and permits operation on all blends of alcohols and gasoline ranging from pure gasoline to pure ethanol and methanol. It is a closed loop electronic feedback controlled fuel injection system (EFI) with exhaust oxygen sensor. The system is used by Toyota Motor Company in their Supra and Cressida models in conjunction with a 3-way catalytic exhaust system. These models meet California exhaust and evaporative emission standards. An unmodified model has been tested on alcohol gasoline blends from pure gasoline to 50% ethanol-50% gasoline and 30% methanol-70% gasoline and found to meet all exhaust and evaporative emissions standards. A Cressida with modified EFI system is currently being tested. It is capable of operating on pure gasoline, pure methanol or ethanol and all intermediate blends. The testing to date shows that the vehicle meets all exhaust emissions standards while operating over the blend range from pure gasoline to pure ethanol while maintaining driveability and energy based fuel economy. The paper will present the total test evidence for all gasoline-alcohol blends. This will include exhaust and evaporative emissions, fuel economy and driveability as determined in accordance with United States Federal Test Procedures. Additionally, the paper will report experiences accumulated from road operation of the vehicle over a six-month period.

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.

Orbit effects on impurity transport in a rotating plasma

International Nuclear Information System (INIS)

Wong, K.L.; Cheng, C.Z.

1988-01-01

In 1985, very high ion temperature plasmas were first produced in TFTR with co-injecting neutral beams in low current, low density plasmas. This mode of operation is called the energetic ion mode in which the plasma rotates at very high speed. It was found that heavy impurities injected into these plasmas diffused out very quickly. In this paper, the authors calculate the impurity ion orbits in a rotating tokamak plasma based on the equation of motion in the frame that rotates with the plasma. It is shown that heavy particles in a rotating plasma can drift away from magnetic surfaces significantly faster. Particle orbits near the surface of a rotating tokamak are also analyzed. During impurity injection experiments, freshly ionized impurities near the plasma surface are essentially stationary in the laboratory frame and they are counter-rotating in the plasma frame with co-beam injection. The results are substantiated by numeral particle simulation. The computer code follows the impurity guiding center positions by integrating the equation of motion with the second order predictor-corrector method

Fuel exchange device for FBR type reactor

International Nuclear Information System (INIS)

Onuki, Koji.

1993-01-01

The device of the present invention can provide fresh fuels with a rotational angle aligned with the direction in the reactor core, so that the fresh fuels can be inserted being aligned with apertures of the reactor core even if a self orientation mechanism should fail to operate. That is, a rotational angle detection means (1) detects the rotational angle of fresh fuels before insertion to the reactor core. A fuel rotational angle control means (2) controls the rotational angle of the fresh fuels by comparing the detection result of the means (1) and the data for the insertion position of the reactor core. A fuel rotation means (3) compensates the rotational angel of the fresh fuels based on the control signal from the means (2). In this way, when the fresh fuels are inserted to the reactor core, the fresh fuels set at the same angle as that for the aperture of the reactor core. Accordingly, even if the self orientation mechanism should not operate, the fresh fuels can be inserted smoothly. As a result, it is possible to save loss time upon fuel exchange and mitigate operator's burden during operation. (I.S.)

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

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

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

Control of Surge in Centrifugal Compressor by Using a Nozzle Injection System: Universality in Optimal Position of Injection Nozzle

Directory of Open Access Journals (Sweden)

Toshiyuki Hirano

2012-01-01

Full Text Available The passive control method for surge and rotating stall in centrifugal compressors by using a nozzle injection system was proposed to extend the stable operating range to the low flow rate. A part of the flow at the scroll outlet of a compressor was recirculated to an injection nozzle installed on the inner wall of the suction pipe of the compressor through the bypass pipe and injected to the impeller inlet. Two types of compressors were tested at the rotational speeds of 50,000 rpm and 60,000 rpm with the parameter of the circumferential position of the injection nozzle. The present experimental results revealed that the optimum circumferential position, which most effectively reduced the flow rate for the surge inception, existed at the opposite side of the tongue of the scroll against the rotational axis and did not depend on the compressor system and the rotational speeds.

Reactor water injection facility

Energy Technology Data Exchange (ETDEWEB)

Yoshikawa, Kazuhiro; Kinoshita, Shoichiro

1997-05-02

A steam turbine and an electric generator are connected by way of a speed convertor. The speed convertor is controlled so that the number of rotation of the electric generator is constant irrespective of the speed change of the steam turbine. A shaft coupler is disposed between the turbine and the electric generator or between the turbine and a water injection pump. With such a constitution, the steam turbine and the electric generator are connected by way of the speed convertor, and since the number of revolution of the electric generator is controlled to be constant, the change of the number of rotation of the turbine can be controlled irrespective of the change of the number of rotation of the electric generator. Accordingly, the flow rate of the injection water from the water injection pump to a reactor pressure vessel can be controlled freely thereby enabling to supply stable electric power. (T.M.)

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.)

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

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

Dimpled/grooved face on a fuel injection nozzle body for flame stabilization and related method

Science.gov (United States)

Uhm, Jong Ho; Johnson, Thomas Edward; Kim, Kwanwoo; Zuo, Baifang

2013-08-20

A fuel injection head for a fuel nozzle used in a gas turbine combustor includes a substantially hollow body formed with an upstream end face, a downstream end face and a peripheral wall extending therebetween. A plurality of pre-mix tubes or passages extend axially through the hollow body with inlets at the upstream end face and outlets at the downstream end face. An exterior surface of the downstream end face is formed with three-dimensional surface features that increase a total surface area of the exterior surface as compared to a substantially flat, planar downstream end face.

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

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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.

Are intra-articular corticosteroid injections better than conventional TENS in treatment of rotator cuff tendinitis in the short run? A randomized study.

Science.gov (United States)

Eyigor, C; Eyigor, S; Kivilcim Korkmaz, O

2010-09-01

Rotator cuff problems are common causes of pain and restriction of movement in shoulder. The aim of this study to compare the effect of intra-articular injection of corticosteroid and conventional transcutaneous electrical nerve stimulator (TENS) treatment in treatment of rotator cuff tendinitis. Subjects were randomly allocated into Group 1 (intra-articular injection of corticosteroid) and Group 2 (conventional transcutaneous electrical nerve stimulation-TENS). Outcome measurements were performed using the Visual Analogue Scale (VAS) for pain, range of motion (ROM), the Shoulder Disability Questionnaire (SDQ), the Short Form-36 (SF-36), and Beck Depression Scale (BDS) questionnaires and paracetamol consumption. In both groups, significant improvement was observed in all weeks in VAS, ROM and SDQ scores (P0.05). In both treatment groups, paracetamol consumption decreased in time (Protator cuff tendinitis. When two treatments are compared, it may be concluded that intra-articular steroid injection was more effective especially in the first weeks regarding pain, ROM and disability. Otherwise, use of TENS allow to patients to increase activity level, improve function and quality of life like that in our study. TENS, as it is cheaper, non-invasive, more easily performed and efficient, may be preferable for the treatment of shoulder pain. Further studies are needed to include these results in the prospective treatment guidelines.

Worldwide Injection Technique Questionnaire Study: Population Parameters and Injection Practices.

Science.gov (United States)

Frid, Anders H; Hirsch, Laurence J; Menchior, Astrid R; Morel, Didier R; Strauss, Kenneth W

2016-09-01

From February 1, 2014, through June 30, 2015, 13,289 insulin-injecting patients from 423 centers in 42 countries took part in one of the largest surveys ever performed in diabetes. The goal was to assess patient characteristics, as well as historical and practical aspects of their injection technique. Results show that 4- and 8-mm needle lengths are each used by nearly 30% of patients and 5- and 6-mm needles each by approximately 20%. Higher consumption of insulin (as measured by total daily dose) is associated with having lipohypertrophy (LH), injecting into LH, leakage from the injection site, and failing to reconstitute cloudy insulin. Glycated hemoglobin values are, on average, 0.5% higher in patients with LH and are significantly higher with incorrect rotation of sites and with needle reuse. Glycated hemoglobin values are lower in patients who distribute their injections over larger injection areas and whose sites are inspected routinely. The frequencies of unexpected hypoglycemia and glucose variability are significantly higher in those with LH, those injecting into LH, those who incorrectly rotate sites, and those who reuse needles. Needles associated with diabetes treatment are the most commonly used medical sharps in the world. However, correct disposal of sharps after use is critically suboptimal. Many used sharps end up in public trash and constitute a major accidental needlestick risk. Use of these data should stimulate renewed interest in and commitment to optimizing injection practices in patients with diabetes. Copyright © 2016 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

Fuel exchanger in FBR type reactor

International Nuclear Information System (INIS)

Shinden, Kazuhiko; Tanaka, Osamu.

1990-01-01

The present invention concerns a fuel exchanger for exchanging fuels in an LMFBR type reactor using liquid metals as coolants. An outer gripper cylinder rotating device for rotating an outer gripper cylinder that holds a gripper is driven, to lower the gripper driving portion and the outer gripper cylinder, fuels are caught by the finger at the top end of the outer gripper cylinder and elevated to extract the fuels from the reactor core. Then, the gripper driving portion casing and the outer gripper cylinder are rotated to rotate the fuels caught by the gripper. Subsequently, the gripper driving portion and the outer gripper cylinder are lowered to charge the fuels in the reactor core. This can directly shuffle the fuels in the reactor core without once transferring the fuels into a reactor storing pot and replacing with other fuels, thereby shortening the shuffling time. (I.N.)

Deterioration of the fuel injection parameters as a result of Common Rail injectors deposit formation

Directory of Open Access Journals (Sweden)

Stępień Zbigniew

2017-01-01

Full Text Available The article describes external and internal Common Rail injectors deposits formed in dynamometer engine simulation tests. It discussed not only the key reasons and factors influencing injector deposit formation but also the resulting way of fuel preparation and engine test approaches. The effects of external coking deposit as well as internal deposits two most common form types that is carboxylic soaps and organic amides on deterioration of the fuel injection parameters were assessed. The assessments covered both deposits impacts on quantitative and qualitative changes of the injectors diagnostic parameters and as a result on deterioration of the injector performance. Finally the comparisons between characteristic of dosage of one fuel injector before test and characteristics few injectors after engine tests of simulated deposit formation were made.

Flexible injection control for fuel consumption and emission reduction in passenger cars?; Flexible Einspritzverlaufsformung: Auch bei PKW-Dieselmotoren ein wirkungsvolles Mittel zur Reduzierung von Verbrauch und Schadstoffemissionen?

Energy Technology Data Exchange (ETDEWEB)

Laumen, H.J.; Koerfer, T.; Lamping, M. [FEV Motorentechnik GmbH, Aachen (Germany); Pischinger, S.; Schmuecker, K.J. [RWTH Aachen (Germany). Lehrstuhl fuer Verbrennungskraftmaschinen

2007-07-01

In the recent decade the Diesel injection technology has been modified significantly. The old cam driven injection systems have been replaced nearly completely by modern Common Rail systems which enable a significantly higher degree of freedom especially with respect to multi-injection strategies and exhaust aftertreatment demands. Nevertheless, cam driven injection systems offered special characteristics which were favorable regarding fuel consumption and emissions. Due to the much higher nozzle opening and closing velocity, the seat throttling effects are widely reduced. Furthermore the fuel injection rate during ignition delay is smaller, compared to today's Common Rail systems. A new type of a piezoelectric Common Rail injector for passenger car engines, called FIRST (Flexible Injection Rate Shaping Tool) is described in this article, which combines both, the flexibility of modern Common Rail injectors as well as the benefits of cam driven injection systems regarding reduced seat throttling effects. Additionally flexible injection rate shaping is enabled by forming the slope of the actuator voltage. Both, the hydraulic behavior and also the engine performance with the new injector are presented in comparison to conventional injectors. The FIRST injector offers a benefit of 20% in PM and CO emission with constant NO{sub x} emission and reduced fuel consumption at part load as a result of the reduced seat throttling. By an optimization of the injection rate shape, the NO{sub x} emissions can be reduced by 40% at constant fuel consumption and PM emissions and without deterioration of NVH level. (orig.)

Effect of Pilot Injection Timings on the Combustion Temperature Distribution in a Single-Cylinder CI Engine Fueled with DME and ULSD

Directory of Open Access Journals (Sweden)

Jeon Joonho

2016-01-01

Full Text Available Many studies of DiMethyl Ether (DME as an alternative fuel in Compression-Ignition (CI engines have been performed. Although diverse DME engine research has been conducted, the investigation of combustion behavior and temperature distribution in the combustion engine has not progressed due to the fact that there is no sooting flame in DME combustion. In order to investigate the combustion characteristics in this study, the KIVA-3 V code was implemented to research various pilot injection strategies on a single-cylinder CI engines with DME and Ultra-Low-Sulfur Diesel (ULSD fuels. The combustion distribution results obtained from the numerical investigation were validated when compared with the measurement of flame temperature behaviors in the experimental approach. This study showed that long intervals between two injection timings enhanced pilot combustion by increasing the ambient pressure and temperature before the start of the main combustion. Different atomization properties between DME and ULSD fuels contributed to the formation of a fuel-air mixture at the nozzle tip and piston lip regions, separately, which strongly affected the temperature distribution of the two fuels. In addition, the pilot injection timing played a vital role in regard to ignition delay and peak combustion temperatures. Exhaust emissions, such as NOx and soot, are related to the local equivalence ratio and temperature in the combustion chamber, also illustrated by the contrary result on a Φ (equivalence ratio – T (temperature map.

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

Simulated effect of timing and Pt quantity injected on On-line NobleChem application on total fuel liftoff

International Nuclear Information System (INIS)

Pop, M.G.; Riddle, J.M.; Lamanna, L.S.; Gregorich, C.; Hoornik, A.

2015-01-01

Total liftoff is a measure of fuel performance and a risk indicator for fuel reliability. Fuel operability and license limits are directly related to the expected total lifetime liftoff. AREVA's continued commitment to zero fuel failure is expressed, among other efforts, in the continued development and improvement of its fuel cladding corrosion and crud risk assessment tools. The AREVA models used to assess and predict crud deposition on BWR cores over their lifespan have been refined by the development and incorporation of the PEZOG tool in response to the move in the industry to the On-Line NobleChem TM (OLNC) technology. PEZOG models the platinum-enhanced zirconium oxide growth of fuel cladding when exposed to platinum during operation. Depending on the local chemistry and radiation condition, noble metals act as catalysts for many reactions, including but not limited to hydrogen oxidation and oxygen reduction. OLNC's intention is to catalyze the hydrogen and oxygen recombination reaction for core internals protection. However, research has indicated that noble metals catalyze the oxygen reduction under the chemistry and radiation conditions as experienced in the pores of crud deposits, and hence, can increase the corrosion rate of zirconium alloy cladding. The developed PEZOG module calculates the oxide thickness as a function of platinum injection strategy. The stratified nature of oxide and crud layers formed on fuel cladding surfaces is reflected in the calculations as are the different platinum interaction in each of the layers. This paper presents examples of the evaluation of various aspects of the platinum injection strategies and their influence on the oxide growth enhancement as applied to conditions of a U.S. plant. (authors)

Effects of Pilot Injection Timing and EGR on Combustion, Performance and Exhaust Emissions in a Common Rail Diesel Engine Fueled with a Canola Oil Biodiesel-Diesel Blend

Directory of Open Access Journals (Sweden)

Jun Cong Ge

2015-07-01

Full Text Available Biodiesel as a clean energy source could reduce environmental pollution compared to fossil fuel, so it is becoming increasingly important. In this study, we investigated the effects of different pilot injection timings from before top dead center (BTDC and exhaust gas recirculation (EGR on combustion, engine performance, and exhaust emission characteristics in a common rail diesel engine fueled with canola oil biodiesel-diesel (BD blend. The pilot injection timing and EGR rate were changed at an engine speed of 2000 rpm fueled with BD20 (20 vol % canola oil and 80 vol % diesel fuel blend. As the injection timing advanced, the combustion pressure, brake specific fuel consumption (BSFC, and peak combustion pressure (Pmax changed slightly. Carbon monoxide (CO and particulate matter (PM emissions clearly decreased at BTDC 20° compared with BTDC 5°, but nitrogen oxide (NOx emissions increased slightly. With an increasing EGR rate, the combustion pressure and indicated mean effective pressure (IMEP decreased slightly at BTDC 20° compared to other injection timings. However, the Pmax showed a remarkable decrease. The BSFC and PM emissions increased slightly, but the NOx emission decreased considerably.

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

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.

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.

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.

Phase characteristics of rare earth elements in metallic fuel for a sodium-cooled fast reactor by injection casting

Energy Technology Data Exchange (ETDEWEB)

Kuk, Seoung Woo, E-mail: swkuk@kaeri.re.kr [Next Generation Fuel Development Division, Korea Atomic Energy Research Institute, Daedeok-daero 989-111, Yuseong-gu, Daejeon, 34057 (Korea, Republic of); Kim, Ki Hwan; Kim, Jong Hwan; Song, Hoon; Oh, Seok Jin; Park, Jeong-Yong; Lee, Chan Bock [Next Generation Fuel Development Division, Korea Atomic Energy Research Institute, Daedeok-daero 989-111, Yuseong-gu, Daejeon, 34057 (Korea, Republic of); Youn, Young-Sang [Nuclear Chemistry Research Division, Korea Atomic Energy Research Institute, Daedeok-daero 989-111, Yuseong-gu, Daejeon, 34057 (Korea, Republic of); Kim, Jong-Yun [Nuclear Chemistry Research Division, Korea Atomic Energy Research Institute, Daedeok-daero 989-111, Yuseong-gu, Daejeon, 34057 (Korea, Republic of); Radiochemistry & Nuclear Nonproliferation, University of Science & Technology, Gajeong-ro 217, Yuseong-gu, Daejeon, 34113 (Korea, Republic of)

2017-04-01

Uranium-zirconium-rare earth (U-Zr-RE) fuel slugs for a sodium-cooled fast reactor were manufactured using a modified injection casting method, and investigated with respect to their uniformity, distribution, composition, and phase behavior according to RE content. Nd, Ce, Pr, and La were chosen as four representative lanthanide elements because they are considered to be major RE components of fuel ingots after pyroprocessing. Immiscible layers were found on the top layers of the melt-residue commensurate with higher fuel slug RE content. Scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDS) data showed that RE elements in the melt-residue were distributed uniformly throughout the fuel slugs. RE element agglomeration did not contaminate the fuel slugs but strongly affected the RE content of the slugs.

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.

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.

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.

Performance and emission study in manifold hydrogen injection with diesel as an ignition source for different start of injection

Energy Technology Data Exchange (ETDEWEB)

Saravanan, N. [ERC-Engines, TATA Motors Ltd, Pimpri, Pune, Maharashtra 411018 (India); Nagarajan, G. [Internal Combustion Engineering Division, Department of Mechanical Engineering, College of Engineering, Guindy, Anna University, Chennai, Tamil Nadu 600 025 (India)

2009-01-15

Over the past two decades there has been a considerable effort to develop and introduce alternative transportation fuels to replace conventional fuels, gasoline and diesel. Environmental issues are the principal driving forces behind this effort. To date the bulk of research has focused on the carbon-based fuels such as reformulated gasoline, methanol and natural gas. One alternative fuel to carbon-based fuels is hydrogen which is considered to be low polluting fuel. In the present experimental investigation hydrogen was injected into the intake manifold by using an injector. Using an electronic control unit (ECU) the injection timing and the duration were controlled. From the results it is observed that the optimum injection timing is at gas exchange top dead center (GTDC). The efficiency improved by about 15% with an increase in NO{sub X} emission by 3% compared to diesel. The smoke emission decreased by almost 100%. A net reduction in carbon emissions was also noticed due to the use of hydrogen. By adopting manifold injection technique the hydrogen-diesel dual fuel engine operates smoothly with a significant improvement in performance and reduction in emissions. (author)

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.

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

Effects of Fuel Quantity on Soot Formation Process for Biomass-Based Renewable Diesel Fuel Combustion

KAUST Repository

Jing, Wei

2016-12-01

Soot formation process was investigated for biomass-based renewable diesel fuel, such as biomass to liquid (BTL), and conventional diesel combustion under varied fuel quantities injected into a constant volume combustion chamber. Soot measurement was implemented by two-color pyrometry under quiescent type diesel engine conditions (1000 K and 21% O2 concentration). Different fuel quantities, which correspond to different injection widths from 0.5 ms to 2 ms under constant injection pressure (1000 bar), were used to simulate different loads in engines. For a given fuel, soot temperature and KL factor show a different trend at initial stage for different fuel quantities, where a higher soot temperature can be found in a small fuel quantity case but a higher KL factor is observed in a large fuel quantity case generally. Another difference occurs at the end of combustion due to the termination of fuel injection. Additionally, BTL flame has a lower soot temperature, especially under a larger fuel quantity (2 ms injection width). Meanwhile, average soot level is lower for BTL flame, especially under a lower fuel quantity (0.5 ms injection width). BTL shows an overall low sooting behavior with low soot temperature compared to diesel, however, trade-off between soot level and soot temperature needs to be carefully selected when different loads are used.

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

An experimental study of injection and spray characteristics of diesel and gasoline blends on a common rail injection system

International Nuclear Information System (INIS)

Han, Dong; Wang, Chunhai; Duan, Yaozong; Tian, Zhisong; Huang, Zhen

2014-01-01

The injection and spray characteristics of diesel and gasoline blends are investigated on a common rail injection system. The injection rate, fuel spray evolution process (tip penetration distance, spray cone angle, projected spray area and relative brightness intensity contour) and microscopic droplet features are analyzed. The results show that diesel and gasoline blends have higher volumetric injection rates, earlier starts of injection and shorter injection delays, but little variances are observed in the mass injection rates for different test fuels. Increased gasoline proportion in the test blends causes slightly decreased spray tip penetration distance but increased spray cone angle. Also, more smaller-size droplets are observed in the fuel jet of the diesel and gasoline blends, indicating that the spray breakup and atomization processes are promoted. - Highlights: • Injection rate and spray characteristics of diesel and gasoline blends are studied. • Diesel and gasoline blends have higher volumetric injection rates. • Earlier starts of injection are found when using diesel and gasoline blends. • Diesel and gasoline blends produce shorter spray penetration but higher cone angle. • The number of small droplets increases in the spray of diesel and gasoline blends

EVALUATION METHOD OF FUEL-EFFICIENT DRIVING IN DUMP TRUCK USING VEHICLE SPEED AND ENGINE ROTATIONAL SPEED

Science.gov (United States)

Hirata, Masafumi; Yamamoto, Tatsuo; Yasui, Toshiaki; Hayashi, Mayu; Takebe, Atsuji; Funahashi, Masashi

In the construction site, the light oil that the construction vehicle such as dump trucks uses accounts for 70 percent of the amount of the energy use. Therefore, the eco-driving education of the construction vehicle is effective in the fuel cost improvement and the CO2 reduction. The eco-driving education can be executed cheap and easily, and a high effect can be expected. However, it is necessary to evaluate the eco-driving situation of the construction vehicle exactly to maintain the educative effect for a long term. In this paper, the method for evaluating the effect of the fuel cost improvement was examined by using the vehicle speed and the engine rotational speed of the dump truck. In this method, "Ideal eco-driving model" that considers the difference between the vehicle model and the running condition (traffic jam etc.) is made. As a result, it is possible to evaluate the fuel consumption improvement effect of a dump truck by the same index.

On the formation of string cavitation inside fuel injectors

Science.gov (United States)

Reid, B. A.; Gavaises, M.; Mitroglou, N.; Hargrave, G. K.; Garner, C. P.; Long, E. J.; McDavid, R. M.

2014-01-01

The formation of vortex or `string' cavitation has been visualised in the flow upstream of the injection hole inlet of an automotive-sized optical diesel fuel injector nozzle operating at pressures up to 2,000 bar. Three different nozzle geometries and three-dimensional flow simulations have been employed to describe how, for two adjacent nozzle holes, their relative positions influenced the formation and hole-to-hole interaction of the observed string cavitation vortices. Each hole was shown to contain two counter-rotating vortices: the first extending upstream on axis with the nozzle hole into the nozzle sac volume and the second forming a single `bridging' string linked to the adjacent hole. Steady-state and transient fuel injection conditions were shown to produce significantly different nozzle-flow characteristics with regard to the formation and interaction of these vortices in the geometries tested, with good agreement between the experimental and simulation results being achieved. The study further confirms that the visualised vortices do not cavitate themselves but act as carriers of gas-phase components within the injector flow.

Effect of Gas Fueling Location on H-mode Access in NSTX

International Nuclear Information System (INIS)

Maingi, R.; Bell, M.; Bell, R.; Biewer, T.; Bush, C.; Chang, C.S.; Gates, D.; Kaye, S.; Kugel, H.; LeBlanc, B.; Maqueda, R.; Menard, J.; Mueller, D.; Raman, R.; Sabbagh, S.; Soukhanovskii, V.

2003-01-01

The dependence of H-mode access on the poloidal location of the gas injection source has been investigated in the National Spherical Torus Experiment (NSTX). We find that gas fueling from the center stack midplane area produces the most reproducible H-mode access with generally the lowest L-H threshold power in lower single-null configuration. The edge toroidal rotation velocity is largest (in direction of the plasma current) just before the L-H transition with center stack midplane fueling, and then reverses direction after the L-H transition. Simulation of these results with a 2-D guiding-center Monte Carlo neoclassical transport code is qualitatively consistent with the trends in the measured velocities. Double-null discharges exhibit H-mode access with gas fueling from either the center stack midplane or center stack top locations, indicating a reduced sensitivity of H-mode access on fueling location in that shape

Influence of Steam Injection and Water-in-Oil Emulsions on Diesel Fuel Combustion Performance

Science.gov (United States)

Sung, Meagan

Water injection can be an effective strategy for reducing NOx because water's high specific heat allows it to absorb heat and lower system temperatures. Introducing water as an emulsion can potentially be more effective at reducing emissions than steam injection due to physical properties (such as microexplosions) that can improve atomization and increase mixing. Unfortunately, the immiscibility of emulsions makes them difficult to work with so they must be mixed properly. In this effort, a method for adequately mixing surfactant-free emulsions was established and verified using high speed cinematography. As the water to fuel mass ratio (W/F) increased, emulsion atomization tests showed little change in droplet size and spray angle, but a shorter overall breakup point. Dual-wavelength planar laser induced fluorescence (D-PLIF) patternation showed an increase in water near the center of the spray. Steam injection flames saw little change in reaction stability, but emulsion flames experienced significant losses in stability that limited reaction operability at higher W/F. Emulsions were more effective at reducing NOx than steam injection, likely because of liquid water's latent heat of vaporization and the strategic injection of water into the flame core. OH* chemiluminescence showed a decrease in heat release for both methods, though the decrease was greater for emulsions. Both methods saw decreases in flame length for W/F 0.15. Lastly, flame imaging showed a shift towards a redder appearance with the addition or more water, as well as a reduction in flame flares.

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.

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.

Fuelling regulation with Electronic fuel injection for small spark ignition engine using Fuzzy Logic

International Nuclear Information System (INIS)

Shah, S.R.; Sahir, M.H.

2004-01-01

The use of Electronic Control systems in automotive applications gives the design engineer greater control over various processes compared with mechanical methods Examples of such electronic control systems are Electronic Fuel Injection (EFI), Traction Control Systems (TCS) and Anti-lock Braking Systems (ABS). In addition, the development of inexpensive and fast microcontrollers has remarkably improve, performance of passive and active safety systems of automobiles, without causing excessive increase in prices of vehicles -a favourable factor from the consumer's perspective. This paper deals with a possible electronic aid for the improvement of power control in a motorcycle. Controlling the speed and power of a motorcycle is difficult; especially on bumpy and uneven terrain. In this paper, the development of an EPI system is discussed, incorporating artificial intelligence to regulate the fuel supplied to the engine. It would minimize wheel slippage and jerky and sudden acceleration which potentially dangerous. It would also reduce production of large quantities of pollutant like hydrocarbons and carbon monoxide. Fuel consumption would also improve during stop-and-go traffic. (author)

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

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

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}).

Computational Fluid Dynamics Analysis of High Injection Pressure Blended Biodiesel

Science.gov (United States)

Khalid, Amir; Jaat, Norrizam; Faisal Hushim, Mohd; Manshoor, Bukhari; Zaman, Izzuddin; Sapit, Azwan; Razali, Azahari

2017-08-01

Biodiesel have great potential for substitution with petrol fuel for the purpose of achieving clean energy production and emission reduction. Among the methods that can control the combustion properties, controlling of the fuel injection conditions is one of the successful methods. The purpose of this study is to investigate the effect of high injection pressure of biodiesel blends on spray characteristics using Computational Fluid Dynamics (CFD). Injection pressure was observed at 220 MPa, 250 MPa and 280 MPa. The ambient temperature was kept held at 1050 K and ambient pressure 8 MPa in order to simulate the effect of boost pressure or turbo charger during combustion process. Computational Fluid Dynamics were used to investigate the spray characteristics of biodiesel blends such as spray penetration length, spray angle and mixture formation of fuel-air mixing. The results shows that increases of injection pressure, wider spray angle is produced by biodiesel blends and diesel fuel. The injection pressure strongly affects the mixture formation, characteristics of fuel spray, longer spray penetration length thus promotes the fuel and air mixing.

System for manipulating radioactive fuel rods within a nuclear fuel assembly

International Nuclear Information System (INIS)

Tolino, R.W.; King, W.E.; Blickenderfer, J.L.; Roth, C.H. Jr.

1987-01-01

A tool is described for manipulating the peripherally located fuel rods of a fuel assembly so that the rods can be visually inspected. The fuel assembly includes top and bottom nozzles, each of which is connected to a support skeleton, as well as grids, and wherein the rods are retained within the grids and confined between the top and bottom nozzles thereof. It consists of: (a) a fixture that is detachably connectable to one of the nozzles of the fuel assembly. The fixture having holes therein, (b) rotating means pivotally mountable within the holes of the fixture for selectively gripping and rotating the rod, and (c) a displacing means mounted on the fixture for reciprocably displacing the rods within the fuel assembly, including a lifting assembly and a push-down assembly for lifting and pushing down a selected one of the rods, respectively, whereby the rods can be selectively rotated, lifted, and pushed down in order to expose portions of the rods which are normally hidden to visual inspection while the nozzles stay connected to the support skeleton and the rods stay confined between the top and bottom nozzles of the fuel assembly

Zinc injection on the EDF fleet monitoring the injection on 12 units

International Nuclear Information System (INIS)

Le-Meur, Gaelle Harmand; Anne-Marie; Stutzmann, Agnes; Taunier, Stephane; Benfarah, Moez; Bretelle, Jean-Luc; Alain, Rocher; Claeys, Myriam; Bonne, Sebastien

2012-09-01

After a first implementation of zinc injection at Bugey 2 and Bugey 4, EDF decided to extend the program to other units of its fleet. 14 more reactors from the French fleet of 58 were chosen in order to - Reduce the radiation sources for curative or preventive (after SGR) reasons - Mitigate stress corrosion cracking on nickel alloys and reduce the rate of generalized corrosion - Prevent the risk of CIPS, mainly after a fuel management change. Zinc injection started on 9 new units in 2011, 1 unit in 2012 and will be extended to 4 other units before the end of 2013. To monitor the injection, EDF has defined a complete program concerning chemistry, radiation protection (dose rate and deposited activities measurements), materials (statistical analysis of SG tube cracks), fuel (oxide measurements) and waste (radiochemical characterization of filters). Reference units were chosen for each field because of the size of the fleet. This paper will detail the different monitoring programs on the EDF plants injecting zinc. (authors)

Ethanol induces rotational behavior in 6-hydroxydopamine lesioned mice

Energy Technology Data Exchange (ETDEWEB)

Silverman, P.B.

1987-03-09

Mice with unilateal striatal lesions created by 6-hydroxydopamine (6HDA) injection were screened for rotational (circling) behavior in response to injection of amphetamine and apomorphine. Those that rotated ipsilaterally in response to amphetamine and contralaterally in response to apomorphine were subsequently challenged with 1 to 3 g/kg (i.p.) ethanol. Surprisingly, ethanol induced dose related contralateral (apomorphine-like) rotation which, despite gross intoxication, was quite marked in most animals. No significant correlation was found between the number of turns made following ethanol and made after apomorphine or amphetamine. 14 references, 2 figures, 1 table.

Observation of plasma rotation driven by static nonaxisymmetric magnetic fields in a tokamak.

Science.gov (United States)

Garofalo, A M; Burrell, K H; DeBoo, J C; deGrassie, J S; Jackson, G L; Lanctot, M; Reimerdes, H; Schaffer, M J; Solomon, W M; Strait, E J

2008-11-07

We present the first evidence for the existence of a neoclassical toroidal rotation driven in a direction counter to the plasma current by nonaxisymmetric, nonresonant magnetic fields. At high beta and with large injected neutral beam momentum, the nonresonant field torque slows down the plasma toward the neoclassical "offset" rotation rate. With small injected neutral beam momentum, the toroidal rotation is accelerated toward the offset rotation, with resulting improvement in the global energy confinement time. The observed magnitude, direction, and radial profile of the offset rotation are consistent with neoclassical theory predictions.

Advanced Optical Diagnostic Methods for Describing Fuel Injection and Combustion Flowfield Phenomena

Science.gov (United States)

Locke, Randy J.; Hicks, Yolanda R.; Anderson, Robert C.

2004-01-01

Over the past decade advanced optical diagnostic techniques have evolved and matured to a point where they are now widely applied in the interrogation of high pressure combusting flows. At NASA Glenn Research Center (GRC), imaging techniques have been used successfully in on-going work to develop the next generation of commercial aircraft gas turbine combustors. This work has centered on providing a means by which researchers and designers can obtain direct visual observation and measurements of the fuel injection/mixing/combustion processes and combustor flowfield in two- and three-dimensional views at actual operational conditions. Obtaining a thorough understanding of the chemical and physical processes at the extreme operating conditions of the next generation of combustors is critical to reducing emissions and increasing fuel efficiency. To accomplish this and other tasks, the diagnostic team at GRC has designed and constructed optically accessible, high pressurer high temperature flame tubes and sectar rigs capable of optically probing the 20-60 atm flowfields of these aero-combustors. Among the techniques employed at GRC are planar laser-induced fluorescence (PLIF) for imaging molecular species as well as liquid and gaseous fuel; planar light scattering (PLS) for imaging fuel sprays and droplets; and spontaneous Raman scattering for species and temperature measurement. Using these techniques, optical measurements never before possible have been made in the actual environments of liquid fueled gas turbines. 2-D mapping of such parameters as species (e.g. OH-, NO and kerosene-based jet fuel) distribution, injector spray angle, and fuel/air distribution are just some of the measurements that are now routinely made. Optical imaging has also provided prompt feedback to researchers regarding the effects of changes in the fuel injector configuration on both combustor performance and flowfield character. Several injector design modifications and improvements have

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)

Nozzle flow and atomization characteristics of ethanol blended biodiesel fuel

Energy Technology Data Exchange (ETDEWEB)

Park, Su Han; Suh, Hyun Kyu; Lee, Chang Sik [Department of Mechanical Engineering, Graduate School of Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul, 133-791 (Korea)

2010-01-15

This study was conducted to investigate the injection and atomization characteristics of biodiesel-ethanol blended fuel. The injection performance of biodiesel-ethanol blended fuel was analyzed from the injection rate characteristics using the injection rate measuring system, and the effective injection velocity and effective spray diameter using the nozzle flow model. Moreover, the atomization characteristics, such as local and overall SMD distributions, overall axial velocity and droplet arrival time were analyzed and compared with these from diesel and biodiesel fuels to obtain the atomization characteristics of biodiesel-ethanol blended fuel. It was revealed that ethanol fuel affects the decrease of the peak injection rate and the shortening of the injection delay due to the decrease of fuel properties, such as fuel density and dynamic viscosity. In addition, the ethanol addition improved the atomization performance of biodiesel fuel, because the ethanol blended fuel has a low kinematic viscosity and surface tension, then that has more active interaction with the ambient gas, compared to BD100. (author)

Mitigation of divertor heat flux by high-frequency ELM pacing with non-fuel pellet injection in DIII-D

Directory of Open Access Journals (Sweden)

A. Bortolon

2017-08-01

Full Text Available Experiments have been conducted on DIII-D investigating high repetition rate injection of non-fuel pellets as a tool for pacing Edge Localized Modes (ELMs and mitigating their transient divertor heat loads. Effective ELM pacing was obtained with injection of Li granules in different H-mode scenarios, at frequencies 3–5 times larger than the natural ELM frequency, with subsequent reduction of strike-point heat flux (Bortolon et al., Nucl. Fus., 56, 056008, 2016. However, in scenarios with high pedestal density (∼6 ×1019m−3, the magnitude of granule triggered ELMs shows a broad distribution, in terms of stored energy loss and peak heat flux, challenging the effectiveness of ELM mitigation. Furthermore, transient heat-flux deposition correlated with granule injections was observed far from the strike-points. Field line tracing suggest this phenomenon to be consistent with particle loss into the mid-plane far scrape-off layer, at toroidal location of the granule injection.

Treatment of Partial Rotator Cuff Tear with Ultrasound-guided Platelet-rich Plasma

Directory of Open Access Journals (Sweden)

Vetrivel Chezian Sengodan

2017-01-01

Full Text Available Background: The treatment of symptomatic partial rotator cuff tear has presented substantial challenge to orthopaedic surgeons as it can vary from conservative to surgical repair. Researches have established the influence of platelet rich plasma in healing damaged tissue. Currently very few data are available regarding the evidence of clinical and radiological outcome of partial rotator cuff tear treated with ultrasound guided platelet rich plasma injection in English literature. Materials and Methods: 20 patients with symptomatic partial rotator cuff tears were treated with ultrasound guided platelet rich plasma injection. Before and after the injection of platelet rich plasma scoring was done with visual analogue score, Constant shoulder score, and UCLA shoulder score at 8 weeks and third month. A review ultrasound was performed 8 weeks after platelet rich plasma injection to assess the rotator cuff status. Results: Our study showed statistically significant improvements in 17 patients in VAS pain score, constant shoulder score and UCLA shoulder score. No significant changes in ROM were noted when matched to the contra-lateral side (P < 0.001 at the 3 month follow-up. The study also showed good healing on radiological evaluation with ultrasonogram 8 weeks after platelet rich plasma injection. Conclusion: Ultrasound guided platelet rich plasma injection for partial rotator cuff tears is an effective procedure that leads to significant decrease in pain, improvement in shoulder functions, much cost-effective and less problematic compared to a surgical treatment.

The development of a wood fuel gasification plant utilising short rotation coppice and forestry residues: project ARBRE

International Nuclear Information System (INIS)

Pitcher, K.F.; Lundbergt, H.

1997-01-01

This paper will discuss the development of ARBRE Energy, a joint venture company that includes Yorkshire Environmental of the United Kingdom and Tenniska Processer AB of Sweden. The project will establish 2000 hectares of short rotation coppices, some of which will be organically fertilized with digested sewage sludges, to provide 80% of the fuel requirements of a biomass integrated gasification combined cycle (BIGCC) electricity generation plant. The remaining 20% of the fuel requirements will come from forestry waste, although in the first 5 years all the fuel will come from the forestry sources until the coppices are mature. The project will construct a gasification plant at Eggborough, North Yorkshire, England, which will provide gas to a gas turbine and steam turbine generation system, producing 10 MW and exporting 8 MW of electricity. It has been included in the 1993 tranche of the UK's Non Fossil Fuel Obligation (NFFO) and has gained financial support from the European Commission's THERMIE programme as a targeted BIGCC project. The project's technical and environmental effects and benefits will be examined in detail, together with the award of its planning permit and agreement on its operating license. (author)

Simultaneous Feedback Control of Plasma Rotation and Stored Energy on the DIII-D Tokamak

International Nuclear Information System (INIS)

Scoville, J.T.; Ferron, J.R.; Humphreys, D.A.; Walker, M.L.

2006-01-01

One of the major modifications made to the DIII-D tokamak during the 2005 Long Torus Opening was the rotation of one of the four two-source neutral beam injection systems. Prior to this modification, all beams injected power with a component in the same direction as the usual plasma current ('' co-injection ''). Starting in early 2006, two of the seven beams inject with a component in the opposite direction ('' counter-injection ''). This new capability allows, for the first time, a partial decoupling of the injected energy and momentum during neutral beam heating experiments. An immediate advantage of mixed co- and counter-injection beams is the capability to control the plasma rotation velocity. High beta plasmas can now be studied over a wide range of the plasma rotation velocity. The stabilizing effect of rotation on the resistive wall mode (RWM), for example, can be directly compared to the stabilization achieved by external feedback coils. This is an advantage over previous techniques to control plasma rotation, such as magnetic braking, which have had only limited success. We describe development and implementation of a model-based control algorithm for simultaneous regulation of plasma rotation and beta. The model includes the two relevant plasma states (plasma rotation and stored energy), and describes the dynamic effects of the relevant actuators on those states. The actuators include the applied beam torque and beam power, which depend on the amount of co and counter-injected beams. Implementation of the model-based control within the plasma control system (PCS) [B.G. Penaflor, et al, '' Current Status of DIII-D Plasma Control System Computer Upgrades,'' Fusion Eng. and Design 71 (2004) 47] requires real-time measurements of the plasma rotation, obtained from the charge exchange recombination (CER) diagnostic, and stored energy calculated by the real-time EFIT equilibrium reconstruction. Details of this model and its development, and a comparison with

Public perceptions of short rotation coppice

International Nuclear Information System (INIS)

Sadler, R.

1993-01-01

The ''Wood as a Fuel'' programme - which funded the research covered in this report - is one of the renewable energy development programmes managed by ETSU (the Energy Technology Support Unit) for the Department of Trade and Industry. This national programme is developing the production and use of fuel wood from two main sources - forestry residues and short rotation coppice. Wood fuel from short rotation coppice offers the greater potential - energy equivalent to 10 mtce (million tonnes of coal equivalent) could be produced annually from 1 million hectares of land. This programme is now well established, with ten trial coppice sites in operation, plus some 40 others. A number of successfully willow and poplar clones have been selected for different soil conditions, and machinery for planting and harvesting has been developed. Local consortia of farmers and users are being established to provide long-term markets for the wood fuel produced. (author)

Multi-component vapor-liquid equilibrium model for LES of high-pressure fuel injection and application to ECN Spray A

NARCIS (Netherlands)

Matheis, Jan; Hickel, S.

2018-01-01

We present and evaluate a two-phase model for Eulerian large-eddy simulations (LES) of liquid-fuel injection and mixing at high pressure. The model is based on cubic equations of state and vapor-liquid equilibrium calculations and can represent the coexistence of supercritical states and

Preliminary pellet injection experiment in the Gamma 10 tandem mirror

Energy Technology Data Exchange (ETDEWEB)

Kawamori, Eiichirou; Tamano, Teruo; Nakashima, Yousuke; Yoshikawa, Masayuki; Kobayashi, Shinji; Cho, Teruji; Ishii, Kameo; Yatsu, Kiyoshi [Plasma Research Center, University of Tsukuba, Tsukuba, Ibaraki (Japan); Mase, Atsushi [Advanced Sceince and Technology Center for Cooperative Research, Kyushu University, Kasuga, Fukuoka (Japan)

2000-07-01

In the GAMMA 10 tandem mirror, pellet injection experiments have been started as a solution for the density limit problem. This is the first pellet injection experiment in open systems. We describe the possibilities of confinement of pellet fueled particles. For that, we measure the number of end loss particles and compare them with pellet fueled ones in various conditions of confining potentials. The deterioration of confining potential with the pellet injection is a fundamental issue. The results show that the ion confining potential recover faster than central electron temperature due to thermal barrier. We also consider the operating space for fueling method. It is demonstrated that the operating space for pellet injection exceeds gas fueled one on hot ion mode plasmas. (author)

Experimental research of variable rotation speed ICE-based electric power station

Directory of Open Access Journals (Sweden)

Dar’enkov Andrey

2017-01-01

Full Text Available Developing variable rotation speed ICE-based stand-alone electric power stations which can supply distant regions and autonomous objects with electricity are of scientific interest due to the insufficient study. The relevance of developing such electric power stations is determined by their usage is to provide a significant fuel saving as well as increase ICE motor service life. The article describes the electric station of autonomous objects with improved fuel economy. The article describes multivariate characteristic. Multivariate characteristic shows the optimal frequency of rotation of the internal combustion engine. At this rotational speed there is the greatest fuel economy.

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

Effects of Supercritical Environment on Hydrocarbon-fuel Injection

Institute of Scientific and Technical Information of China (English)

Bongchul Shin; Dohun Kim; Min Son; Jaye Koo

2017-01-01

In this study,the effects of environment conditions on decane were investigated.Decane was injected in subcritical and supercritical ambient conditions.The visualization chamber was pressurized to 1.68 MPa by using nitrogen gas at a temperature of 653 K for subcritical ambient conditions.For supercritical ambient conditions,the visualization chamber was pressurized to 2.52 MPa by using helium at a temperature of 653 K.The decane injection in the pressurized chamber was visualized via a shadowgraph technique and gradient images were obtained by a post processing method.A large variation in density gradient was observed at jet interface in the case of subcritical injection in subcritical ambient conditions.Conversely,for supercritical injection in supercritical ambient conditions,a small density gradient was observed at the jet interface.In a manner similar to that observed in other cases,supercritical injection in subcritical ambient conditions differed from supercritical ambient conditions such as sphere shape liquid.Additionally,there were changes in the interface,and the supercritical injection core width was thicker than that in the subcritical injection.Furthermore,in cases with the same injection conditions,the change in the supercritical ambient normalized core width was smaller than the change in the subcritical ambient normalized core width owing to high specific heat at the supercritical injection and small phase change at the interface.Therefore,the interface was affected by the changing ambient condition.Given that the effect of changing the thermodynamic properties of propellants could be essential for a variable thrust rocket engine,the effects of the ambient conditions were investigated experimentally.

Effects of supercritical environment on hydrocarbon-fuel injection

Science.gov (United States)

Shin, Bongchul; Kim, Dohun; Son, Min; Koo, Jaye

2017-04-01

In this study, the effects of environment conditions on decane were investigated. Decane was injected in subcritical and supercritical ambient conditions. The visualization chamber was pressurized to 1.68 MPa by using nitrogen gas at a temperature of 653 K for subcritical ambient conditions. For supercritical ambient conditions, the visualization chamber was pressurized to 2.52 MPa by using helium at a temperature of 653 K. The decane injection in the pressurized chamber was visualized via a shadowgraph technique and gradient images were obtained by a post processing method. A large variation in density gradient was observed at jet interface in the case of subcritical injection in subcritical ambient conditions. Conversely, for supercritical injection in supercritical ambient conditions, a small density gradient was observed at the jet interface. In a manner similar to that observed in other cases, supercritical injection in subcritical ambient conditions differed from supercritical ambient conditions such as sphere shape liquid. Additionally, there were changes in the interface, and the supercritical injection core width was thicker than that in the subcritical injection. Furthermore, in cases with the same injection conditions, the change in the supercritical ambient normalized core width was smaller than the change in the subcritical ambient normalized core width owing to high specific heat at the supercritical injection and small phase change at the interface. Therefore, the interface was affected by the changing ambient condition. Given that the effect of changing the thermodynamic properties of propellants could be essential for a variable thrust rocket engine, the effects of the ambient conditions were investigated experimentally.

Detection of failed fuel rods in shrouded BWR fuel assemblies

International Nuclear Information System (INIS)

Baero, G.; Boehm, W.; Goor, B.; Donnelly, T.

1988-01-01

A manipulator and an ultrasonic testing (UT) technique were developed to identify defective fuel rods in shrouded BWR fuel assemblies. The manipulator drives a UT probe axially through the bottom tie plate into the water channels between the fuel rods. The rotating UT probe locates defective fuel rods by ingressed water which attenuates the UT-signal. (author)

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.

The Effect of Fuel Dose Division on The Emission of Toxic Components in The Car Diesel Engine Exhaust Gas

Directory of Open Access Journals (Sweden)

Pietras Dariusz

2016-09-01

Full Text Available The article discusses the effect of fuel dose division in the Diesel engine on smoke opacity and composition of the emitted exhaust gas. The research activities reported in the article include experimental examination of a small Diesel engine with Common Rail type supply system. The tests were performed on the engine test bed equipped with an automatic data acquisition system which recorded all basic operating and control parameters of the engine, and smoke opacity and composition of the exhaust gas. The parameters measured during the engine tests also included the indicated pressure and the acoustic pressure. The tests were performed following the pre-established procedure in which 9 engine operation points were defined for three rotational speeds: 1500, 2500 and 3500 rpm, and three load levels: 25, 40 and 75 Nm. At each point, the measurements were performed for 7 different forms of fuel dose injection, which were: the undivided dose, the dose divided into two or three parts, and three different injection advance angles for the undivided dose and that divided into two parts. The discussion of the obtained results includes graphical presentation of contests of hydrocarbons, carbon oxide, and nitrogen oxides in the exhaust gas, and its smoke opacity. The presented analyses referred to two selected cases, out of nine examined engine operation points. In these cases the fuel dose was divided into three parts and injected at the factory set control parameters. The examination has revealed a significant effect of fuel dose division on the engine efficiency, and on the smoke opacity and composition of the exhaust gas, in particular the content of nitrogen oxides. Within the range of low loads and rotational speeds, dividing the fuel dose into three parts clearly improves the overall engine efficiency and significantly decreases the concentration of nitrogen oxides in the exhaust gas. Moreover, it slightly decreases the contents of hydrocarbons and

Performance and fuel conversion efficiency of a spark ignition engine fueled with iso-butanol

International Nuclear Information System (INIS)

Irimescu, Adrian

2012-01-01

Highlights: ► Iso-butanol use in a port injection spark ignition engine. ► Fuel conversion efficiency calculated based on chassis dynamometer measurements. ► Combined study of engine efficiency and air–fuel mixture temperature. ► Excellent running characteristics with minor fuel system modifications. ► Up to 11% relative drop in part load efficiency due to incomplete fuel vaporization. -- Abstract: Alcohols are increasingly used as fuels for spark ignition engines. While ethanol is most commonly used, long chain alcohols such as butanol feature several advantages like increased heating value and reduced corrosive action. This study investigated the effect of fueling a port injection engine with iso-butanol, as compared to gasoline operation. Performance levels were maintained within the same limits as with the fossil fuel without modifications to any engine component. An additional electronic module was used for increasing fuel flow by extending the injection time. Fuel conversion efficiency decreased when the engine was fueled with iso-butanol by up to 9% at full load and by up to 11% at part load, calculated as relative values. Incomplete fuel evaporation was identified as the factor most likely to cause the drop in engine efficiency.

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)

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.

Injection characteristics of dimethyl ether

Energy Technology Data Exchange (ETDEWEB)

Glensvig, M.

1996-09-01

Dimethyl ether (DME) has proved to be a new ultra-clean alternative fuel for diesel engines. Engine tests have shown considerably lower NO{sub x} emissions, no particle emissions and lower noise compared to that obtained from normal diesel engine operation. DME also has demonstrated favorable response to Exhaust Gas Recirculation (EGR). The purpose of this investigation was to achieve a better understanding of the fundamental spray behavior of DME. Fundamental spray behaviour was characterized by fuel spray penetration and angle, atomization and droplet size and evaporation. The influence of fuel characteristics, nozzle geometry and ambient pressure on the DME and diesel spray behavior was investigated. Fuel was injected into an unheated injection chamber with a ambient pressure of 15 bar and 25 bar, respectively, giving a simplified simulation of the environment in an operating engine. Two nozzles were studied: a single hole nozzle and a pintle nozzle. A conventional fuel injection system was used for both nozzles. Injection parameters of RPM, throttle position, fuel line length and chamber environment were held constant for both nozzles. The sprays were visualized using schlieren and high speed photography. Results show that the general appearance of the DME spray is similar to that of diesel spray. The core of the DME spray seems less dense and the spray tip less sharp compared to diesel spray, indicating smaller droplets with a lower momentum in the core of the DME spray. Schlieren film shows that with both DME and diesel fuel, the spray tip only consists of liquid and that evaporation occurs after a brief time interval. Penetration of DME is about one third that of diesel using the pintle nozzle. Also, the spray angle is considerably larger for the DME spray compared to the diesel spray. A comparatively smaller difference in penetration is observed using the hole nozzle. Differences in penetration for the hole nozzle are within the limit of the penetration

Chemical composition and source of fine and nanoparticles from recent direct injection gasoline passenger cars: Effects of fuel and ambient temperature

Science.gov (United States)

Fushimi, Akihiro; Kondo, Yoshinori; Kobayashi, Shinji; Fujitani, Yuji; Saitoh, Katsumi; Takami, Akinori; Tanabe, Kiyoshi

2016-01-01

Particle number, mass, and chemical compositions (i.e., elemental carbon (EC), organic carbon (OC), elements, ions, and organic species) of fine particles emitted from four of the recent direct injection spark ignition (DISI) gasoline passenger cars and a port fuel injection (PFI) gasoline passenger car were measured under Japanese official transient mode (JC08 mode). Total carbon (TC = EC + OC) dominated the particulate mass (90% on average). EC dominated the TC for both hot and cold start conditions. The EC/TC ratios were 0.72 for PFI and 0.88-1.0 (average = 0.92) for DISI vehicles. A size-resolved chemical analysis of a DISI car revealed that the major organic components were the C20-C28 hydrocarbons for both the accumulation-mode particles and nanoparticles. Contribution of engine oil was estimated to be 10-30% for organics and the sum of the measured elements. The remaining major fraction likely originated from gasoline fuel. Therefore, it is suggested that soot (EC) also mainly originated from the gasoline. In experiments using four fuels at three ambient temperatures, the emission factors of particulate mass were consistently higher with regular gasoline than with premium gasoline. This result suggest that the high content of less-volatile compounds in fuel increase particulate emissions. These results suggest that focusing on reducing fuel-derived EC in the production process of new cars would effectively reduce particulate emission from DISI cars.

Monolithic fuel injector and related manufacturing method

Science.gov (United States)

Ziminsky, Willy Steve [Greenville, SC; Johnson, Thomas Edward [Greenville, SC; Lacy, Benjamin [Greenville, SC; York, William David [Greenville, SC; Stevenson, Christian Xavier [Greenville, SC

2012-05-22

A monolithic fuel injection head for a fuel nozzle includes a substantially hollow vesicle body formed with an upstream end face, a downstream end face and a peripheral wall extending therebetween, an internal baffle plate extending radially outwardly from a downstream end of the bore, terminating short of the peripheral wall, thereby defining upstream and downstream fuel plenums in the vesicle body, in fluid communication by way of a radial gap between the baffle plate and the peripheral wall. A plurality of integral pre-mix tubes extend axially through the upstream and downstream fuel plenums in the vesicle body and through the baffle plate, with at least one fuel injection hole extending between each of the pre-mix tubes and the upstream fuel plenum, thereby enabling fuel in the upstream plenum to be injected into the plurality of pre-mix tubes. The fuel injection head is formed by direct metal laser sintering.

Fuel processor for fuel cell power system. [Conversion of methanol into hydrogen

Science.gov (United States)

Vanderborgh, N.E.; Springer, T.E.; Huff, J.R.

1986-01-28

A catalytic organic fuel processing apparatus, which can be used in a fuel cell power system, contains within a housing a catalyst chamber, a variable speed fan, and a combustion chamber. Vaporized organic fuel is circulated by the fan past the combustion chamber with which it is in indirect heat exchange relationship. The heated vaporized organic fuel enters a catalyst bed where it is converted into a desired product such as hydrogen needed to power the fuel cell. During periods of high demand, air is injected upstream of the combustion chamber and organic fuel injection means to burn with some of the organic fuel on the outside of the combustion chamber, and thus be in direct heat exchange relation with the organic fuel going into the catalyst bed.

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.

Variable volume combustor with aerodynamic fuel flanges for nozzle mounting

Science.gov (United States)

McConnaughhay, Johnie Franklin; Keener, Christopher Paul; Johnson, Thomas Edward; Ostebee, Heath Michael

2016-09-20

The present application provides a combustor for use with a gas turbine engine. The combustor may include a number of micro-mixer fuel nozzles and a fuel injection system for providing a flow of fuel to the micro-mixer fuel nozzles. The fuel injection system may include a number of support struts supporting the fuel nozzles and for providing the flow of fuel therethrough. The fuel injection system also may include a number of aerodynamic fuel flanges connecting the micro-mixer fuel nozzles and the support struts.

Skin pre-ablation and laser assisted microjet injection for deep tissue penetration.

Science.gov (United States)

Jang, Hun-Jae; Yeo, Seonggu; Yoh, Jack J

2017-04-01

For conventional needless injection, there still remain many unresolved issues such as the potential for cross-contamination, poor reliability of targeted delivery dose, and significantly painstaking procedures. As an alternative, the use of microjets generated with Er:YAG laser for delivering small doses with controlled penetration depths has been reported. In this study, a new system with two stages is evaluated for effective transdermal drug delivery. First, the skin is pre-ablated to eliminate the hard outer layer and second, laser-driven microjet penetrates the relatively weaker and freshly exposed epidermis. Each stage of operation shares a single Er:YAG laser that is suitable for skin ablation as well as for the generation of a microjet. In this study, pig skin is selected for quantification of the injection depth based on the two-stage procedure, namely pre-ablation and microjet injection. The three types of pre-ablation devised here consists of bulk ablation, fractional ablation, and fractional-rotational ablation. The number of laser pulses are 12, 18, and 24 for each ablation type. For fractional-rotational ablation, the fractional beams are rotated by 11.25° at each pulse. The drug permeation in the skin is evaluated using tissue marking dyes. The depth of penetration is quantified by a cross sectional view of the single spot injections. Multi-spot injections are also carried out to control the dose and spread of the drug. The benefits of a pre-ablation procedure prior to the actual microjet injection to the penetration is verified. The four possible combinations of injection are (a) microjet only; (b) bulk ablation and microjet injection; (c) fractional ablation and microjet injection; and (d) fractional-rotational ablation and microjet injection. Accordingly, the total depth increases with injection time for all cases. In particular, the total depth of penetration attained via fractional pre-ablation increased by 8 ∼ 11% and that of fractional-rotational

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.

Multiplexed electrospray scaling for liquid fuel injection

International Nuclear Information System (INIS)

Waits, C Mike; Hanrahan, Brendan; Lee, Ivan

2010-01-01

Evaporation and space-charge requirements are evaluated to understand the effect of device scaling and fuel preheating for a liquid fuel injector using a multiplexed electrospray (MES) configuration in compact combustion applications. This work reveals the influence of the droplet diameter, droplet velocity and droplet surface temperature as well as the surrounding gas temperature on the size and performance of microfabricated MES. Measurements from MES devices are used in the model to accurately account for the droplet diameter versus flow rate relationship, the minimum droplet diameter and the relevant droplet velocities. A maximum extractor electrode to ground electrode distance of 3.1 mm required to overcome space-charge forces is found to be independent of voltage or droplet velocity for large levels of multiplexing. This maximum distance also becomes the required evaporation length scale which imposes minimum fuel pre-heating requirements for large flow densities. Required fuel preheating is therefore evaluated for both ethanol and 1-butanol with combustor parameters relevant to fuel reformation, thermoelectric conversion, thermophotovoltaic conversion and thermionic conversion

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)

Influence of fuel temperature on dispersion and decay of BDE sprays; Einfluss der Kraftstofftemperatur auf die Ausbreitung und den Zerfall von BDE-Sprays

Energy Technology Data Exchange (ETDEWEB)

Schmitz, I.; Beyrau, F.; Leipertz, A. [Erlangen-Nuernberg Univ., Erlangen (Germany). Lehrstuhl fuer Technische Thermodynamik

2007-07-01

As an example for a highly - developed technical spray system, the spray vaporization of a multi - hole injector used for the gasoline direct injection (GDI) has been investigated. Experiments were conducted in a heated injection chamber for different chamber pressures, fuels and fuel temperatures. In this investigation pure rotational coherent anti-Stokes Raman spectroscopy (RCARS) has been applied to the study of vaporizing sprays in combination with other laser techniques. Gas phase temperatures inside the sprays have been determined with high spatial and temporal resolution. A temperature drop of about 30 K was measured for all fuel temperatures studied. Droplet sizes and number densities have been measured using phase Doppler anemometry, and the correlation of these results with two - dimensional laser sheet Mie scattering images and laser-induced exciplex fluorescence allows an improved interpretation of the spray vaporization process. Furthermore under the influence of flash boiling a reduction of the mean drop size D10 up to 30% could be observed. (orig.)

Current drive by neutral beams, rotating magnetic fields and helicity injection in compact toroids

International Nuclear Information System (INIS)

Farengo, R.

2002-01-01

A Monte-Carlo code is used to study neutral beam current drive in Spheromaks. The exact particle trajectories are followed in the self-consistent equilibria calculated including the beam current. Reducing Z(eff) does not increase the current drive efficiency because the reduction of the stopping cross section is compensated by an increase in the electron canceling current. Significant changes in the safety factor profile can be produced with relatively low beam currents. Minimum dissipation states of a flux core spheromak sustained by helicity injection are presented. Helicity balance is used as a constraint and the resistivity is considered to be non-uniform. Two types of relaxed states are found; one has a central core of open flux surrounded by a toroidal region of closed flux surfaces and the other has the open flux wrapped around the closed flux surfaces. Non-uniform resistivity effects can be very important due to the changes they produce in the safety factor profile. A hybrid, fluid electrons particle ions, code is employed to study ion dynamics in FRCs sustained by rotating magnetic fields. (author)

Laser-Based Spatio-Temporal Characterisation of Port Fuel Injection (PFI Sprays

Directory of Open Access Journals (Sweden)

C. T. N. Anand

2010-06-01

Full Text Available In the present work, detailed laser-based diagnostic experiments were conducted to characterise the spray from low pressure 2-hole and 4-hole Port Fuel Injection (PFI injectors. The main objective of the work included obtaining quantitative information of the spatio-temporal spray structure of such low-pressure gasoline sprays. A novel approach involving a combination of techniques such as Mie scattering, Granulometry, and Laser Sheet Dropsizing (LSD was used to study the spray structure. The droplet sizes, distributions with time, Sauter Mean Diameters (SMD, droplet velocities, cone angles and spray tip penetrations of the sprays from the injectors were determined. The spray from these injectors is found to be ‘pencil like’ and not dispersed as in high pressure sprays. The application of the above mentioned techniques provides two-dimensional SMD contours of the entire spray at different instants of time, with reasonable accuracy.

Steam injection for heavy oil recovery: Modeling of wellbore heat efficiency and analysis of steam injection performance

International Nuclear Information System (INIS)

Gu, Hao; Cheng, Linsong; Huang, Shijun; Li, Bokai; Shen, Fei; Fang, Wenchao; Hu, Changhao

2015-01-01

Highlights: • A comprehensive mathematical model was established to estimate wellbore heat efficiency of steam injection wells. • A simplified approach of predicting steam pressure in wellbores was proposed. • High wellhead injection rate and wellhead steam quality can improve wellbore heat efficiency. • High wellbore heat efficiency does not necessarily mean good performance of heavy oil recovery. • Using excellent insulation materials is a good way to save water and fuels. - Abstract: The aims of this work are to present a comprehensive mathematical model for estimating wellbore heat efficiency and to analyze performance of steam injection for heavy oil recovery. In this paper, we firstly introduce steam injection process briefly. Secondly, a simplified approach of predicting steam pressure in wellbores is presented and a complete expression for steam quality is derived. More importantly, both direct and indirect methods are adopted to determine the wellbore heat efficiency. Then, the mathematical model is solved using an iterative technique. After the model is validated with measured field data, we study the effects of wellhead injection rate and wellhead steam quality on steam injection performance reflected in wellbores. Next, taking cyclic steam stimulation as an example, we analyze steam injection performance reflected in reservoirs with numerical reservoir simulation method. Finally, the significant role of improving wellbore heat efficiency in saving water and fuels is discussed in detail. The results indicate that we can improve the wellbore heat efficiency by enhancing wellhead injection rate or steam quality. However, high wellbore heat efficiency does not necessarily mean satisfactory steam injection performance reflected in reservoirs or good performance of heavy oil recovery. Moreover, the paper shows that using excellent insulation materials is a good way to save water and fuels due to enhancement of wellbore heat efficiency

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.

Dimethyl Ether in Diesel Fuel Injection Systems

DEFF Research Database (Denmark)

Sorenson, Spencer C.; Glensvig, M.; Abata, D. L.

1998-01-01

A study of the behaviour of DME in diesel injection systems. A discussion of the effects of compressibility of DME on compression work and wave propagation.DME spray shapes and penetration rates......A study of the behaviour of DME in diesel injection systems. A discussion of the effects of compressibility of DME on compression work and wave propagation.DME spray shapes and penetration rates...

Hydrogen as automotive fuel

International Nuclear Information System (INIS)

Dini, D.; Ciancia, A.; Pede, G.; Sglavo, V.; ENEA, Rome

1992-01-01

An assessment of the technical/economic feasibility of the use of hydrogen as an automotive fuel is made based on analyses of the following: the chemical- physical properties of hydrogen in relation to its use in internal combustion engines; the modifications necessary to adapt internal combustion engines to hydrogen use; hydrogen fuel injection systems - with water vapour injection, cryogenic injection, and the low or high pressure injection of hydrogen directly into the combustion chamber; the current commercialization status of hydrogen automotive fuels; energy efficiency ratings; environmental impacts; in-vehicle storage systems - involving the use of hydrides, high pressure systems and liquid hydrogen storage systems; performance in terms of pay-load ratio; autonomous operation; and operating costs. The paper concludes that, considering current costs for hydrogen fuel production, distribution and use, at present, the employment of hydrogen fuelled vehicles is feasible only in highly polluted urban environments where the innovative vehicle's air pollution abatement characteristics would justify its high operating costs as compared with those of conventional automotive alternatives

Factors affecting diesel fuel degradation using a bespoke high-pressure fuel system rig

OpenAIRE

Gopalan, Kesavan; Smith, Christopher; Pickering, Simon; Chuck, Christopher; Bannister, Christopher

2018-01-01

Recently, there has been automotive industry-wide impetus to reduce overall diesel vehicle emissions and fuel consumption by increasing fuel injection pressures within common rail systems. Many production fuel injection systems are now capable of delivering rail pressures of 1800-2000 bar with those able to achieve 3000 bar under development. In addition, there has been a gradual increase in the permitted FAME content in EN590 diesel from 5% to 7% with further increases to 10% proposed. With ...

Conceptual design of a commercial tokamak hybrid reactor fueling system

Energy Technology Data Exchange (ETDEWEB)

Matney, K.D.; Donnert, H.J.; Yang, T.F.

1979-12-01

A conceptual design of a fuel injection system for CTHR (Commercial Tokamak Hybrid Reactor) is discussed. Initially, relative merits of the cold-fueling concept are compared with those of the hot-fueling concept; that is, fueling where the electron is below 1 eV is compared with fueling where the electron temperature exceeds 100 eV. It is concluded that cold fueling seems to be somewhat more free of drawbacks than hot fueling. Possible implementation of the cold-fueling concept is exploited via frozen-pellet injection. Several methods of achieving frozen-pellet injection are discussed and the light-gas-gun approach is chosen from these possibilities. A modified version of the ORNL Neutral Gas Shielding Model is used to simulate the pellet injection process. From this simulation, the penetration-depth dependent velocity requirement is determined. Finally, with the velocity requirement known, a gas-pressure requirement for the proposed conceptual design is established. The cryogenic fuel-injection and fuel-handling systems are discussed. A possible way to implement the conceptual device is examined along with the attendant effects on the total system.

Conceptual design of a commercial tokamak hybrid reactor fueling system

International Nuclear Information System (INIS)

Matney, K.D.; Donnert, H.J.; Yang, T.F.

1979-12-01

A conceptual design of a fuel injection system for CTHR (Commercial Tokamak Hybrid Reactor) is discussed. Initially, relative merits of the cold-fueling concept are compared with those of the hot-fueling concept; that is, fueling where the electron is below 1 eV is compared with fueling where the electron temperature exceeds 100 eV. It is concluded that cold fueling seems to be somewhat more free of drawbacks than hot fueling. Possible implementation of the cold-fueling concept is exploited via frozen-pellet injection. Several methods of achieving frozen-pellet injection are discussed and the light-gas-gun approach is chosen from these possibilities. A modified version of the ORNL Neutral Gas Shielding Model is used to simulate the pellet injection process. From this simulation, the penetration-depth dependent velocity requirement is determined. Finally, with the velocity requirement known, a gas-pressure requirement for the proposed conceptual design is established. The cryogenic fuel-injection and fuel-handling systems are discussed. A possible way to implement the conceptual device is examined along with the attendant effects on the total system

Conceptual design of a commercial tokamak hybrid reactor fueling system

International Nuclear Information System (INIS)

Matney, K.D.; Donnert, H.J.; Yang, T.F.

1979-12-01

A conceptual design of a fuel injection system for CTHR (Commercial Tokamak Hybrid Reactor) is discussed. Initially, relative merits of the cold-fueling concept are compared with those of the hot-fueling concept; that is, fueling where the electron temperature is below 1 eV is compared with fueling where the electron temperature exceeds 100 eV. It is concluded that cold fueling seems to be somewhat more free of drawbacks than hot fueling. Possible implementation of the cold-fueling concept is exploited via frozen-pellet injection. Several methods of achieving frozen-pellet injection are discussed and the light-gas-gun approach is chosen from these possibilities. A modified version of the ORNL Neutral Gas Shielding Model is used to simulate the pellet injection process. From this simulation, the penetration-depth dependent velocity requirement is determined. Finally, with the velocity requirement known, a gas-pressure requirement for the proposed conceptual design is established. The cryogenic fuel-injection and fuel-handling systems are discussed. A possible way to implement the conceptual device is examined along with the attendant effects on the total system

Human and bovine spinal disc mechanics subsequent to trypsin injection.

Science.gov (United States)

Alsup, Jeremy; Bishop, Timothy; Eggett, Dennis; Bowden, Anton E

2017-10-01

To investigate the biomechanical effects of injections of a protease on the characteristics of bovine coccygeal and human lumbar disc motion segments. Mechanics of treated tissues were measured immediately after injection and 3 h after injection. Motion segments underwent axial rotation and flexion-extension loading. Stiffness and neutral zone parameters experienced significant changes over time, with bovine tissues more strongly affected than human cadaver tissues. This was true in both axial rotation and flexion-extension. The treatment type significantly affected the neutral zone measurements in axial rotation. Hysteresis parameters were impacted by control injections. The extrapolation of bovine coccygeal motion testing results to human lumbar disc mechanics is not yet practical. The injected treatment may have a smaller impact on disc mechanics than time in testing. Viscoelasticity of human lumbar discs may be impacted by any damage to the annulus fibrosis induced by needlestick. Preclinical testing of novel spinal devices is essential to the design validation and regulatory processes, but current testing techniques rely on cadaveric testing of primarily older spines with essentially random amounts of disc degeneration. The present work investigates the viability of using trypsin injections to create a more uniform preclinical model of disc degeneration from a mechanics perspective, for the purpose of testing spinal devices. Such a model would facilitate translation of new spinal technologies to clinical practice.

Electrically controlled fuel injection device for internal combustion engines with air quantity meter. Elektrisch gesteuerte Kraftstoffeinspritzeinrichtung fuer Brennkraftmaschinen mit Luftmengenmesser

Energy Technology Data Exchange (ETDEWEB)

Kraus, B; Soell, W

1980-12-11

The invention concerns an electrically controlled preferably intermittently working fuel injection device for internal combustion engines with a throttle valve, a solenoid operated injection valve and a transistor circuit, which supplies electrical pulses used to open the injection valve synchronously to the revolution of the crankshaft. The invention is characterized by the fact that an electrical control device is provided, which extends the individual opening pulses in thrust operation (with the throttle valve closed or nearly closed and with a working speed above the speed). The extension produced by the control device decreases from a value at about 20% for the maximum speed to a value of 0 for the tickover speed. Details of the transistor control are made clear by detailed circuit diagrams and 5 patent claims.

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

Fabrication of nuclear fuel by powder injection moulding: Study of the binders systems and the de-binding of feedstock containing actinide powder

International Nuclear Information System (INIS)

Bricout, J.

2012-01-01

Powder Injection Moulding (PIM) is identified as an innovative process for the nuclear fuel fabrication. Technological breakthrough compared to the current process of powder metallurgy, the impact of actinide powder's specificities on the different steps of PIM is performed. Alumina powders simulating actinide powder have been implemented with a reference binders system. Thermal and rheological studies show the injectability and the de-binding of feedstocks with adequate solid loading (≥50 %vol), thanks to the de-agglomeration during the mixing step, which allow to obtain net shape fuel pellet. Specific surface area of powders, acting as a key role in behaviour's feedstocks, has been integrated in analysis models of viscosity prediction according to the shear rate. Also conducted studies on uranium oxide powder show that the selected binders systems, which have a compatible rheological behaviour with PIM process, impact the de-agglomeration of powder and final microstructure of the fuel pellet, consistent with the results obtained on alumina powders. Independent behaviour of binders and uranium oxide powder, showing no adverse chemical reaction against the PIM process, show a residual mass of carbon of about 150 ppm after sintering. Binders system using polystyrene, resistant to radiolysis phenomena and loadable more than 50 %(vol) of actinide powder, shows the promising potential of PIM process for the fuel fabrication. (author) [fr

An EIS alternative for impedance measurement of a high temperature PEM fuel cell stack based on current pulse injection

DEFF Research Database (Denmark)

Jeppesen, Christian; Araya, Samuel Simon; Sahlin, Simon Lennart

2017-01-01

In this paper a method for estimating the fuel cell impedance is presented, namely the current pulse injection (CPI) method, which is well suited for online implementation. This method estimates the fuel cell impedance and unlike electrochemical impedance spectroscopy (EIS), it is simple...... to implement at a low cost. This makes it appealing as a characterization method for on-line diagnostic algorithms. In this work a parameter estimation method for estimation of equivalent electrical circuit (EEC) parameters, which is suited for on-line use is proposed. Tests on a 10 cell high temperature PEM...... fuel cell show that the method yields consistent results in estimating EEC parameters for different current pulse at different current loads, with a low variance. A comparison with EIS shows that despite its simplicity the response of CPI can reproduce well the impedance response of the high...

PEM fuel cells with injection moulded bipolar plates of highly filled graphite compounds; PEM-Brennstoffzellen mit spritzgegossenen Bipolarplatten aus hochgefuelltem Graphit-Compound

Energy Technology Data Exchange (ETDEWEB)

Kreuz, Can

2008-04-11

This work concerns with the injection moulding of highly filled graphite compounds to bipolar plates for PEM fuel cells in a power output range between 100 - 500 Watts. A particular focus is laid on the combination of the three multidisciplinary scopes like material development, production technology and component development / design. The results of the work are specified by the process-oriented characterisation of the developed and manufactured bipolar plates as well as their application in a functioning fuel cell. (orig.)

Nuclear fuel replacement device

International Nuclear Information System (INIS)

Ritz, W.C.; Robey, R.M.; Wett, J.F.

1984-01-01

A fuel handling arrangement for a liquid metal cooled nuclear reactor having a single rotating plug eccentric to the fuel core and a fuel handling machine radially movable along a slot in the plug with a transfer station disposed outside the fuel core but covered by the eccentric plug and within range of movement of said fuel handling machine to permit transfer of fuel assemblies between the core and the transfer station. (author)

Procedure Oriented Torsional Anatomy of the Forearm for Spasticity Injection.

Science.gov (United States)

Chiou-Tan, Faye; Cianca, John; John, Joslyn; Furr-Stimming, Erin; Pandit, Sindhu; Taber, Katherine H

2015-01-01

: This is the second in a series of articles related to the concept of "torsional" anatomy. The objective of this article is to provide musculoskeletal ultrasound (MSKUS) anatomy of the forearm in the position of hemispastic flexion as a reference relevant to needle procedures. The MSKUS images were obtained in a healthy human subject. Marker dots were placed over common injection sites in the forearm for spasticity. The MSKUS probe was centered over each dot to obtain a cross-sectional view. A pair of MSKUS images was recorded for each site: the first in anatomic neutral and second in hemiparetic spastic position. The images were compared side to side. In addition, a video recording was made at each site to track the movement of the muscles and nerves during internal rotation. The pronator teres (PT) rotated medially and the brachialis and biceps tendon rotated in view. In addition, the median nerve became more superficial. The flexor carpi radialis rotated medially and was replaced by PT and the median nerve. The flexor carpi ulnaris and flexor digitorum profundus rotated medially and were replaced by the flexor carpi radialis, PT and median nerve. The flexor digitorum superficialis was replaced by the brachioradialis, extensor carpi radialis brevis, and radial nerve. The brachioradialis was replaced by the extensor carpi radialis brevis and extensor digitorum communis. Intended muscle targets rotate out of view and injection range. These are replaced by other muscles and nerves that could inadvertently be injected. This potentially could result in both increased complications and decreased efficacy of the procedure. It is hoped that this series of images will increase the accuracy and safety of needle placement for spasticity injections in the forearm.

Method and device for taking out spent fuel

International Nuclear Information System (INIS)

Kono, Takayuki; Shimamoto, Takijiro; Otsuka, Shiomi.

1994-01-01

Both ends of a fuel assembly are cut and removed, and spacers are removed into a single body of a fuel cladding tube. A plurality of the fuel cladding tubes as single bodies are sent into a ring-like electrode. An arc forming electric power source is actuated, to form arcs between the fuel cladding tube and the ring-like electric power source. A magnetic field forming power source is actuated, to form magnetic fields around the ring-like electrode by solenoid coils. The direction of the magnetic fluxes in this magnetic fields intersect the arcs. Then, the arcs are applied with a rotational force by the magnetic fields formed by the solenoid coils and rotate on the surface of the fuel cladding tube and the inner surface of the ring-like electrode. The fuel cladding tube is exhausted circumferentially uniformly by the rotational arcs. Since spent fuels are taken out by melting and scattering the fuel cladding tube by the heat and force of the arcs, the operation is facilitated. (I.N.)

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.

Oil injection into the blast furnace

Energy Technology Data Exchange (ETDEWEB)

Dongsheng Liao; Mannila, P.; Haerkki, J.

1997-12-31

Fuel injection techniques have been extensively used in the commercial blast furnaces, a number of publications concerning the fuels injection have been reported. This present report only summarizes the study achievements of oil injection due to the research need the of authors, it includes the following parts: First, the background and the reasons reducing coke rate of oil injection are analyzed. Reducing coke rate and decreasing the ironmaking costs are the main deriving forces, the contents of C, H and ash are direct reasons reducing coke rate. It was also found that oil injection had great effects on the state of blast furnace, it made operation stable, center gas flow develop fully, pressure drop increase, descent speed of burden materials decrease and generation of thermal stagnation phenomena, the quality of iron was improved. Based on these effects, as an ideal mean, oil injection was often used to adjust the state of blast furnace. Secondly, combustion behavior of oil in the raceway and tuyere are discussed. The distribution of gas content was greatly changed, the location of CO, H{sub 2} generation was near the tuyere; the temperature peak shifts from near the raceway boundary to the tuyere. Oxygen concentration and blast velocity were two important factors, it was found that increasing excess oxygen ratio 0.9 to 1.3, the combustion time of oil decreases 0.5 msec, an increase of the blast velocity results in increasing the flame length. In addition, the nozzle position and oil rate had large effects on the combustion of oil. Based on these results, the limit of oil injection is also discussed, soot formation is the main reason limiting to further increase oil injection rate, it was viewed that there were three types of soot which were generated under blast furnace operating conditions. The reason generating soot is the incomplete conversion of the fuel. Finally, three methods improving combustion of oil in the raceway are given: Improvement of oil

Spray-controlled combustionprocess with piezo injection; Strahlgefuehrtes Brennverfahren mit Piezo-Benzineinspritzung

Energy Technology Data Exchange (ETDEWEB)

Schaupp, U.; Altenschmidt, F.; Bertsch, D.; Laudenbach, N. [DaimlerChrysler AG, Stuttgart (Germany)

2007-07-01

The novel 2nd generation injection system of Mercedes-Benz have resulted in reduced fuel consumption and lower emissions while improving the engine performance. The piezo technology is a great technical advance. The characteristic field range in which stratified charge operation is possible has been extended since the first generation of injection systems. Lower fuel consumption is achieved not only in normal traffic but also when cruising on motorways at constant speed. The advantages are noticeable not only in the test cycle but also in real operation. The piezo injection valve was not available on the market and had to be constructed, including the 200 bar high-pressure fuel injection system. The stability of the injection system and the good mixing characteristics resulted in an optimally combustible mixture at the spark plug. Apart from stability in stratified charge operation, the possibility of multiple injection also has further advantages and potentials in terms of consumption and emissions. (orig.)

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.

Fuel Maps for the GEP 6.5LT Engine When Operating on at J/JP-8 Fuel Blends at Ambient and Elevated Temperatures

Science.gov (United States)

2015-04-01

system. The new calibrated fuel injection pump and injectors were installed, and the fuel injection timing of the new fuel injection system was set to...Product 6.5L Turbocharged diesel engine at two inlet temperature conditions. The GEP 6.5LT engine represents legacy diesel engine design with...derived cetane number DF-2 Diesel Fuel number 2 ft Foot HEFA Hydro-treated Esters and Fatty Acid(s) HP or hp Horsepower hr Hour in Inch in³ cubic

Hydrogen pellet injection into Alcator C

International Nuclear Information System (INIS)

Greenwald, M.

1983-09-01

A four-shot pneumatic pellet injector, based on an ORNL design, has been built and operated on the Alcator C tokamak at MIT. The injector fires four independently-timed frozen hydrogen pellets with velocities in the range 8 x 10 4 - 1 x 10 5 cm/sec. Each contains 6 x 10 19 particles which corresponds to = 2 x 10 14 /cm 3 . The objectives of this experiment are to study pellet fueling and penetration, particle confinement, dependence of energy confinement on density profile and fueling mode, and edge physics and recycling as a function of fueling mode. Typical pre-injection plasmas have had anti n/sub e/ = 2 - 3 x 10 14 , Bt = 80 - 100 kG, Ip = 400 - 500 kA, T/sub e/(0) = 1200 - 1500 ev. A single pellet injected into this plasma will roughly double the electron density. Record plasma densities have been obtained by multiple injections. Line average densities in excess of 8 x 10 14 have been achieved, with highly peaked profiles. Central densities of 1.5 - 2 x 10 15 have been measured

Rotational discontinuities in anisotropic plasmas

International Nuclear Information System (INIS)

Omidi, N.

1992-01-01

The kinetic structure of rotational discontinuities (RDs) in anisotropic plasmas with T perpendicular /T parallel > 1 is investigated by using a one-dimensional electromagnetic hybrid code. To form the RD, a new approach is used where the plasma is injected from one boundary and reflected from the other, resulting in the generation of a traveling fast shock and an RD. Unlike the previously used methods, no a priori assumptions are made regarding the initial structure (i.e. width or sense of rotation) of the rotational discontinuity. The results show that across the RD both the magnetic field strength and direction, as well as the plasma density change. Given that such a change can also be associated with an intermediate shock, the Rankine-Hugoniot relations are used to confirm that the observed structures are indeed RDs. It is found that the thickness of RDs is a few ion inertial lengths and is independent of the rotation angle. Also, the preferred sense of rotation is in the electron sense; however, RDs with a rotation angle larger than 180 degree are found to be unstable, changing their rotation to a stable ion sense

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)

Injection of zinc in plants of ANAV. Impact on fuel and operation experience; Inyeccion de cinc en las plantas de ANAV. Impacto sobre el combustible y experiencia de operacion

Energy Technology Data Exchange (ETDEWEB)

Doncell, N.; Gago, J. L.

2015-07-01

Zinc injection performed in the three ANAV (Asociacion Nuclear Asco-Vandellos) plants is part of an overall primary water chemistry program, material management and dose reduction program. The application of zinc shown significant benefits in radiation field reduction as well as in mitigation of PWSCC initiation. Although zinc injection also reduces general corrosion rates and consequently reduces corrosion product transport to the fuel, and evaluation of the risks with respect to fuel performance should be done. ANAV and ENUSA, following industry recommendations, have coordinated the task related to the viability of the program in Asco and Vandellos including monitoring, inspections and control parameters. finally, this article includes a comprehensive review of operating experience and an assessment of fuel performance effects. (Author)

Development of lean burn gas engines using pilot fuel for ignition source; Developpement d'un moteur a gaz avec pre-injection de carburant pour la source d'allumage

Energy Technology Data Exchange (ETDEWEB)

Sakonji, T.; Saito, H.; Sakurai, T. [Tokyo Gas Co., Ltd. (Japan); Hirashima, T.; Kanno, K. [Nissan Diesel Motor Co., Ltd. (Japan)

2000-07-01

A development was conducted to investigate the performance of an open chamber gas engine with pilot fuel for ignition source. Experiments were conducted by using a gas engine equipped with a common-rail injection system. Main gas fuel is supplied to the engine cylinder, and then a small quantity of diesel fuel (approximately 1 % of total fuel energy input) was injected into the main chamber for ignition. The single cylinder prototype gas engine has demonstrated superior performance, such as, a shaft-end thermal efficiency of 36.7% with NO{sub x} level of 0.4 g/kW-h, which equals those of conventional spark ignited pre-chamber lean burn gas engines. For the next step, the multi-cylinder gas engine has been developed. That has 138 mm bore, 142 mm stroke, V8 configuration and 229 kW engine output 1500 rpm. This engine can also run with only diesel fuel for Standby-Power-Concurrent Co-generation. (authors)

Fueling of magnetic-confinement devices

International Nuclear Information System (INIS)

Milora, S.L.

1981-01-01

A general overview of the fueling of magnetic confinement devices is presented, with particular emphasis on recent experimental results. Various practical fueling mechanisms are considered, such as cold gas inlet (or plasma edge fueling), neutral beam injection, and injection of high speed cryogenic hydrogen pellets. The central role played by charged particle transport and recycle of plasma particles from material surfaces in contact with the plasma is discussed briefly. The various aspects of hydrogen pellet injection are treated in detail, including applications to the production of high purity startup plasmas for stellarators and other devices, refueling of tokamak plasmas, pellet ablation theory, and the technology and performance characteristics of low and high speed pellet injectors

Gas injection system in the Tara center cell

International Nuclear Information System (INIS)

Brau, K.; Post, R.S.; Sevillano, E.

1985-11-01

Precise control of the gas fueling is essential to the successful operation of tandem mirror plasmas. Improper choice of fueling location, magnetic geometry, and gas injection rates can prevent potential and thermal barrier formation, as well as reduce the energy confinement time. In designing the new gas injection configuration for the Tara center cell, the following issues were addressed: RF potential barriers, gas leakage, and charge exchange recombination. 2 refs., 6 figs

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

Melt Fragmentation Characteristics of Metal Fuel with Melt Injection Mass during Initiating Phase of SFR Severe Accidents

Energy Technology Data Exchange (ETDEWEB)

Heo, Hyo; Lee, Min Ho; Bang, In Cheol [Ulsan National Institute of Science and Technology, Ulsan (Korea, Republic of); Jerng, Dong Wook [Chung-Ang Univ., Seoul (Korea, Republic of)

2016-05-15

The PGSFR has adopted the metal fuel for its inherent safety under severe accident conditions. However, this fuel type is not demonstrated clearly yet under the such severe accident conditions. Additional experiments for examining these issues should be performed to support its licensing activities. Under initiating phase of hypothetic core disruptive accident (HCDA) conditions, the molten metal could be better dispersed and fragmented into the coolant channel than in the case of using oxide fuel. This safety strategy provides negative reactivity driven by a good dispersion of melt. If the coolant channel does not sufficient coolability, the severe recriticality would occur within the core region. Thus, it is important to examine the extent of melt fragmentation. The fragmentation behaviors of melt are closely related to a formation of debris shape. Once the debris shape is formed through the fragmentation process, its coolability is determined by the porosity or thermal conductivity of the melt. There were very limited studies for transient irradiation experiments of the metal fuel. These studies were performed by Transient Reactor Test Facility (TREAT) M series tests in U.S. The TREAT M series tests provided basic information of metal fuel performance under transient conditions. The effect of melt injection mass was evaluated in terms of the fragmentation behaviors of melt. These behaviors seemed to be similar between single-pin and multi-pins failure condition. However, the more melt was agglomerated in case of multi-pins failure.

Iron making technology with fuels and other materials injection in blast furnace tuyeres. Part 1. Auxiliary fuels characteristics and its influence in the blast furnace process; Tecnologia de fabricacion de arrabio con la inyeccion de combustibles y otros materiales por toberas en el horno alto. I parte. Caracteristicas de los combustibles auxiliares y su influencia en el proceso del horno alto

Energy Technology Data Exchange (ETDEWEB)

Garcia, L. [Union de Empresas de Recuperacion de Materias Primas. Ciudad de La Habana (Cuba); Cores, A.; Formoso, A. [Centro Nacional de Investigaciones Metalurgicas. Madrid (Spain); Babich, A.; Yaroshevskii, S. [Universidad Estatal Tecnologica de Donetsk. Ucrania (Ukraine)

1998-06-01

The injection of fuels by tuyeres in the blast furnace is a used practice in most furnaces with the principal aim to reduce the coke consumption by ton of pig iron produced. The nature of these fuels is very diverse and depends on the resources of each country and of the fuel price. At this moment the coal injection (pulverized and granular) is the most extended practice, and the number of furnaces with facilities for coal injection increases continuously. (Author) 14 refs.

Global-Scale Consequences of Magnetic-Helicity Injection and Condensation on the Sun

Science.gov (United States)

Mackay, Duncan H.; DeVore, C. Richard; Antiochos, Spiro K.

2013-01-01

In the recent paper of Antiochos, a new concept for the injection of magnetic helicity into the solar corona by small-scale convective motions and its condensation onto polarity inversion lines (PILs) has been developed. We investigate this concept through global simulations of the Sun's photospheric and coronal magnetic fields and compare the results with the hemispheric pattern of solar filaments. Assuming that the vorticity of the cells is predominately counter-clockwise/clockwise in the northern/southern hemisphere, the convective motions inject negative/positive helicity into each hemisphere. The simulations show that: (i) On a north-south orientated PIL, both differential rotation and convective motions inject the same sign of helicity which matches that required to reproduce the hemispheric pattern of filaments. (ii) On a high latitude east-west orientated polar crown or sub-polar crown PIL, the vorticity of the cells has to be approximately 2-3 times greater than the local differential rotation gradient in order to overcome the incorrect sign of helicity injection from differential rotation. (iii) In the declining phase of the cycle, as a bipole interacts with the polar field, in some cases helicity condensation can reverse the effect of differential rotation along the East-West lead arm, but not in all cases. The results show that this newly developed concept of magnetic helicity injection and condensation is a viable method to explain the hemispheric pattern of filaments in conjunction with the mechanisms used in Yeates et al. (2008). Future observational studies should focus on determining the vorticity component within convective motions to determine, both its magnitude and latitudinal variation relative to the differential rotation gradient on the Sun.

Reductions of PAH and Soot by Center Air Injection

Directory of Open Access Journals (Sweden)

Kazuhiro Yamamoto

2014-07-01

Full Text Available In this study, to reduce the amount of pollutant PAH and soot in the flame, we examined the burner system equipped with a center air injection. For this purpose, by using PAH-LIF and soot LII, we evaluated relative PAH and soot amounts in both the triple port burner and the conventional co-axial burner (double port burner to discuss effects of center air injection on the formation of PAH and soot. The fuel was propane. In the triple port burner, two different blue flames are observed near the burner rim, followed by bright luminous flames with soot. The flame length is longer when the fuel flow velocity is increased. On the other hand, the flame length is shorter with an increase in internal air flow velocity. As for PAH and soot, these amounts of the triple port burner are much smaller than those of the double port burner. For the triple port burner, due to the center air injection, the fuel consumption occurs in both inner and outer flames. On the other hand, for the double port burner, the oxygen is supplied from one side air, and as a result, the fuel consumption rate is relatively lower. Hence, by the center air injection, the fuel consumption is largely accelerated, resulting in the reduction of PAH and soot.

Neutral beam injection and plasma convection in a magnetic field

International Nuclear Information System (INIS)

Okuda, H.; Hiroe, S.

1988-06-01

Injection of a neutral beam into a plasma in a magnetic field has been studied by means of numerical plasma simulations. It is found that, in the absence of a rotational transform, the convection electric field arising from the polarization charges at the edges of the beam is dissipated by turbulent plasma convection, leading to anomalous plasma diffusion across the magnetic field. The convection electric field increases with the beam density and beam energy. In the presence of a rotational transform, polarization charges can be neutralized by the electron motion along the magnetic field. Even in the presence of a rotational transform, a steady-state convection electric field and, hence, anomalous plasma diffusion can develop when a neutral beam is constantly injected into a plasma. Theoretical investigations on the convection electric field are described for a plasma in the presence of rotational transform. 11 refs., 19 figs

Effects of Zinc Injection on the Cladding Oxide Thickness in the Domestic Nuclear Power Plant

International Nuclear Information System (INIS)

Yoon, Hak Kyu; Kim, Hong Jin; Shin, Jung Cheol

2013-01-01

The first commercial plant for zinc injection demonstration was Farley-2 in 1994, and the effect of zinc injection was successfully demonstrated. Since then the PWR with zinc injection has been increased, there are about 80 PWR with zinc injection in the world in 2012. Zinc injection at the high duty plant has potential risk of increasing the cladding oxide thickness. Zinc injection doesn't affect the cladding corrosion directly but it may negatively affect crud deposit in the subcooled boiling region of the fuel. So the effect of zinc injection on fuel integrity has been evaluated. For low duty plant it is confirmed that zinc injection doesn't affect the fuel integrity. For high duty plant Callaway in U. S. and Vandellos II in Spain were successfully demonstrated but the experience with zinc injection of high duty plant was still lacking. Thus EPRI recommend the fuel surveillance programs for the high duty plant to apply zinc. The High Duty Core Index (HDCI) of most domestic nuclear power plant is above 150 Btu/ft 2 -gal- .deg. F. Those plants with a HDCI of 150 Btu/ft 2 -gal- .deg. F or greater may be considered as 'high duty'. As aforementioned, the experience with zinc injection of high duty plant was lacking. Thus to apply zinc injection in domestic plant with high duty, prudent approach is needed. In this study the effect of zinc injection in Hanul unit 1 with a HDCI of around 150 Btu/ft 2 -gal- .deg. F was evaluated. And in the next study the effect of zinc injection in the plant of HDCI of around 200 Btu/ft 2 -gal- .deg. F will be evaluated. Zinc injection had not caused any increase in oxide thickness in Hanul unit 1. Most of the oxide thickness measurement data with zinc injection are well within the non-zinc injection database. And the computer code which was developed based on non-zinc injection database well predicts oxide thickness for fuel rod with zinc injection. Thus, it can be concluded that zinc injection doesn't accelerate clad corrosion. Based

Fuel assembly gripping device using self-locking mechanism

Energy Technology Data Exchange (ETDEWEB)

Lee, G. M.; Choi, S.; Kim, K. S.; Kim, T. W.; Jeong, K. H.; Park, K. B.; Chang, M. H

1999-07-01

This report presents an actuating principles and structure for two kind of the fuel assembly gripping devices (Gripper-A, B) developed for SMART. The main components of these grippers are push bundle, rotation bundle, upper guide tube and chuck assembly. The rope attached to winch system on moving cask hangs gripper's push bundle. Due to a down-and-up operation of winch system, the push bundle pushes crown teeth shaped rotation bundle and then it is pushed down and rotated counter clockwise. The push-and-pull sequential operation of push bundle makes the rotation bundle is pushed, rotated and returned, moreover it makes the chuck assembly is expanded or shrunk. The expansion and shrinkage motion of chuck assembly makes the gripper latch and release the fuel assembly. Gripper-A suits for the handling of the fuel assembly with square shaped latching hole. Otherwise Gripper-B suits for a circular shaped latching hole. (author). 5 refs., 20 figs.

Fuel assembly gripping device using self-locking mechanism

International Nuclear Information System (INIS)

Lee, G. M.; Choi, S.; Kim, K. S.; Kim, T. W.; Jeong, K. H.; Park, K. B.; Chang, M. H.

1999-07-01

This report presents an actuating principles and structure for two kind of the fuel assembly gripping devices (Gripper-A, B) developed for SMART. The main components of these grippers are push bundle, rotation bundle, upper guide tube and chuck assembly. The rope attached to winch system on moving cask hangs gripper's push bundle. Due to a down-and-up operation of winch system, the push bundle pushes crown teeth shaped rotation bundle and then it is pushed down and rotated counter clockwise. The push-and-pull sequential operation of push bundle makes the rotation bundle is pushed, rotated and returned, moreover it makes the chuck assembly is expanded or shrunk. The expansion and shrinkage motion of chuck assembly makes the gripper latch and release the fuel assembly. Gripper-A suits for the handling of the fuel assembly with square shaped latching hole. Otherwise Gripper-B suits for a circular shaped latching hole. (author). 5 refs., 20 figs

Study of fuel control strategy based on an fuel behavior model for starting conditions; Nenryo kyodo model ni motozuita shidoji no nenryo hosei hosho ni tsuite no kosatsu

Energy Technology Data Exchange (ETDEWEB)

Nakajima, Y; Uchida, M; Iwano, H; Oba, H [Nissan Motor Co. Ltd., Tokyo (Japan)

1997-10-01

We have applied a fuel behavior model to a fuel injection system which we call SOFIS (Sophisticated and Optimized Fuel Injection System) so that we get air/fuel ratio control accuracy and good driveability. However the fuel behavior under starting conditions is still not clear. To meet low emission rules and to get better driveability under starting conditions, better air/fuel ratio control is necessary. Now we have understood the ignition timing, injection timing, and injection pulse width required in such conditions. In former days, we analyzed the state of the air/fuel mixture under cold conditions and made a new fuel behavior model which considered fuel loss such as hydrocarbons and dissolution into oil and so on. Al this time, we have applied this idea to starting. We confirm this new model offers improved air/fuel ratio control. 6 refs., 9 figs., 3 tabs.

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

Effect of 3 months of progressive high-load strength training in patients with rotator cuff tendinopathy: Primary results from the double-blind, randomised, controlled Rotator Cuff Tendinopathy Exercise (RoCTEx) trial

DEFF Research Database (Denmark)

Ingwersen, Kim Gordon; Jensen, Steen Lund; Sørensen, Lilli

2017-01-01

BACKGROUND: Progressive high-load exercise (PHLE) has led to positive clinical results in patients with patellar and Achilles tendinopathy. However, its effects on rotator cuff tendinopathy still need to be investigated. PURPOSE: To assess the clinical effects of PHLE versus low-load exercise (LLE......) among patients with rotator cuff tendinopathy. STUDY DESIGN: Randomized controlled trial; Level of evidence, 1. METHODS: Patients with rotator cuff tendinopathy were recruited and randomized to 12 weeks of PHLE or LLE, stratified for concomitant administration of corticosteroid injection. The primary...... benefit from PHLE over traditional LLE among patients with rotator cuff tendinopathy. Further investigation of the possible interaction between exercise type and corticosteroid injection is needed to establish optimal and potentially synergistic combinations of these 2 factors. REGISTRATION: NCT01984203...

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

Detection device for the failed position in fuels

International Nuclear Information System (INIS)

Tokunaga, Kensuke; Nomura, Teiji; Hiruta, Koji

1985-01-01

Purpose: To detect the failed position of a fuel assembly with ease and safety. Constitution: A fuel assembly is tightly closed in a sipper tube equipped with a gas supply tube and a gas exhaust tube at the upper portion and a purified water injection tube and a draining tube at the lower end. Then, water in the sipper tube is drained to the lower portion of the fuel assembly by the pressure of gases while opening the gas supply tube and the draining tube, and closing the exhaust tube and the injection tube. Then, after closing the gas supply tube and the draining tube while opening theexhaust tube and the injection tube, purified water is injected into the sipper tube from the injection tube to an optional height till the fuel assembly is immersed. Then, after leaving for a predetermined of time, water is sampled and the radioactive material density therein is measured. By changing the injection level of the purified water, since the radioactive material density changes at the failed position, the failed position can be detected with ease. (Sekiya, K.)

Friction and wear properties of high-velocity oxygen fuel sprayed WC-17Co coating under rotational fretting conditions

Science.gov (United States)

Luo, Jun; Cai, Zhenbing; Mo, Jiliang; Peng, Jinfang; Zhu, Minhao

2016-05-01

Rotational fretting which exist in many engineering applications has incurred enormous economic loss. Thus, accessible methods are urgently needed to alleviate or eliminate damage by rotational fretting. Surface engineering is an effective approach that is successfully adopted to enhance the ability of components to resist the fretting damage. In this paper, using a high-velocity oxygen fuel sprayed (HVOF) technique WC-17Co coating is deposited on an LZ50 steel surface to study its properties through Vickers hardness testing, scanning electric microscope (SEM), energy dispersive X-ray spectroscopy (EDX), and X-ray diffractrometry (XRD). Rotational fretting wear tests are conducted under normal load varied from 10 N to 50 N, and angular displacement amplitudes vary from 0.125° to 1°. Wear scars are examined using SEM, EDX, optical microscopy (OM), and surface topography. The experimental results reveal that the WC-17Co coating adjusted the boundary between the partial slip regime (PSR) and the slip regime (SR) to the direction of smaller amplitude displacement. As a result, the coefficients of friction are consistently lower than the substrate's coefficients of friction both in the PSR and SR. The damage to the coating in the PSR is very slight. In the SR, the coating exhibits higher debris removal efficiency and load-carrying capacity. The bulge is not found for the coating due to the coating's higher hardness to restrain plastic flow. This research could provide experimental bases for promoting industrial application of WC-17Co coating in prevention of rotational fretting wear.

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.

Fuel cell membrane hydration and fluid metering

Science.gov (United States)

Jones, Daniel O.; Walsh, Michael M.

1999-01-01

A hydration system includes fuel cell fluid flow plate(s) and injection port(s). Each plate has flow channel(s) with respective inlet(s) for receiving respective portion(s) of a given stream of reactant fluid for a fuel cell. Each injection port injects a portion of liquid water directly into its respective flow channel in order to mix its respective portion of liquid water with the corresponding portion of the stream. This serves to hydrate at least corresponding part(s) of a given membrane of the corresponding fuel cell(s). The hydration system may be augmented by a metering system including flow regulator(s). Each flow regulator meters an injecting at inlet(s) of each plate of respective portions of liquid into respective portion(s) of a given stream of fluid by corresponding injection port(s).

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.

Dependence of the L- to H-mode Power Threshold on Toroidal Rotation and the Link to Edge Turbulence Dynamics

International Nuclear Information System (INIS)

McKee, G.; Gohil, P.; Schlossberg, D.; Boedo, J.; Burrell, K.; deGrassie, J.; Groebner, R.; Makowski, M.; Moyer, R.; Petty, C.; Rhodes, T.; Schmitz, L.; Shafer, M.; Solomon, W.; Umansky, M.; Wang, G.; White, A.; Xu, X.

2008-01-01

The injected power required to induce a transition from L-mode to H-mode plasmas is found to depend strongly on the injected neutral beam torque and consequent plasma toroidal rotation. Edge turbulence and flows, measured near the outboard midplane of the plasma (0.85 < r/a < 1.0) on DIII-D with the high-sensitivity 2D beam emission spectroscopy (BES) system, likewise vary with rotation and suggest a causative connection. The L-H power threshold in plasmas with the ion (del)B drift away from the X-point decreases from 4-6 MW with co-current beam injection, to 2-3 MW with near zero net injected torque, and to <2 MW with counter injection. Plasmas with the ion (del)B drift towards the X-point exhibit a qualitatively similar though less pronounced power threshold dependence on rotation. 2D edge turbulence measurements with BES show an increasing poloidal flow shear as the L-H transition is approached in all conditions. At low rotation, the poloidal flow of turbulent eddies near the edge reverses prior to the L-H transition, generating a significant poloidal flow shear that exceeds the measured turbulence decorrelation rate. This increased poloidal turbulence velocity shear may facilitate the L-H transition. No such reversal is observed in high rotation plasmas. The poloidal turbulence velocity spectrum exhibits a transition from a Geodesic Acoustic Mode zonal flow to a higher-power, lower frequency, zero-mean-frequency zonal flow as rotation varies from co-current to balanced during a torque scan at constant injected neutral beam power, perhaps also facilitating the L-H transition. This reduced power threshold at lower toroidal rotation may benefit inherently low-rotation plasmas such as ITER

Plasma rotation study in Tore Supra radio frequency heated plasmas

International Nuclear Information System (INIS)

Chouli, Bilal

2014-01-01

Toroidal flows are found to improve the performance of the magnetic confinement devices with increase of the plasma stability and confinement. In ITER or future reactors, the torque from NBI should be less important than in present-day tokamaks. Consequently, it is of interest to study other intrinsic mechanisms that can give rise to plasma rotation in order to predict the rotation profile in experiments. Intriguing observations of plasmas rotation have been made in radio frequency (RF) heated plasmas with little or no external momentum injection. Toroidal rotation in both the direction of the plasma current (co-current) and in the opposite direction (counter-current) has been observed depending on the heating schemes and plasma performance. In Tore Supra, most observations in L-mode plasmas have been in the counter-current direction. However, in this thesis, we show that in lower hybrid current drive (LHCD), the core toroidal rotation increment is in co- or counter-current direction depending on the plasma current amplitude. At low plasma current the rotation change is in the co-current direction while at high plasma current, the change is in the counter-current direction. In both low and high plasma current cases, rotation increments are found to increase linearly with the injected LH power. Several mechanisms in competition which can induce co- or counter-current rotation in Tore Supra LHCD plasmas are investigated and typical order of magnitude are discussed in this thesis. (author) [fr

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.

Analysis of toroidal rotation data for the DIII-D tokamak

International Nuclear Information System (INIS)

John, H.St.; Burrell, K.H.; Groebner, R.; DeBoo, J.; Gohil, P.

1989-01-01

Both poloidal and toroidal rotation are observed during routine neutral beam heating operation of the DIII-D tokamak. Poloidal rotation results and the empirical techniques used to measure toroidal and poloidal rotation speeds are described by Groebner et al. Here we concentrate on the analysis of recent measurements of toroidal rotation made during diverted, H-mode operation of the DIII-D tokamak during co- and counter-neutral beam injection of hydrogen into deuterium plasmas. Similar studies have been previously reported for Doublet III, ASDEX, TFTR, JET and other tokamaks. (author) 13 refs., 4 figs

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.

Fueling moving ring field-reversed mirror reactor plasmas

International Nuclear Information System (INIS)

Felber, F.S.

1980-01-01

The concept of small fusion reactors is being studied jointly by Lawrence Livermore Laboratory General Atomic Company, and Pacific Gas and Electric Company. The objective is to investigate alternatives and then to develop a conceptual design for a small reactor that could produce useful, though not necessarily economical, energy by the late 1980s. Three methods of fueling a small moving ring field-reversed mirror are considered: injection of fuel pellets accelerated by laser ablation, injection of fuel pellets accelerated by deflagration-gun ablation, and direct injection of plasma by a deflagration gun. 13 refs

Effects of Zinc Injection on the Cladding Oxide Thickness in the Domestic Nuclear Power Plant

Energy Technology Data Exchange (ETDEWEB)

Yoon, Hak Kyu; Kim, Hong Jin; Shin, Jung Cheol [KEPCO Nuclear Fuel Co. Ltd., Daejeon (Korea, Republic of)

2013-10-15

The first commercial plant for zinc injection demonstration was Farley-2 in 1994, and the effect of zinc injection was successfully demonstrated. Since then the PWR with zinc injection has been increased, there are about 80 PWR with zinc injection in the world in 2012. Zinc injection at the high duty plant has potential risk of increasing the cladding oxide thickness. Zinc injection doesn't affect the cladding corrosion directly but it may negatively affect crud deposit in the subcooled boiling region of the fuel. So the effect of zinc injection on fuel integrity has been evaluated. For low duty plant it is confirmed that zinc injection doesn't affect the fuel integrity. For high duty plant Callaway in U. S. and Vandellos II in Spain were successfully demonstrated but the experience with zinc injection of high duty plant was still lacking. Thus EPRI recommend the fuel surveillance programs for the high duty plant to apply zinc. The High Duty Core Index (HDCI) of most domestic nuclear power plant is above 150 Btu/ft{sup 2}-gal- .deg. F. Those plants with a HDCI of 150 Btu/ft{sup 2}-gal- .deg. F or greater may be considered as 'high duty'. As aforementioned, the experience with zinc injection of high duty plant was lacking. Thus to apply zinc injection in domestic plant with high duty, prudent approach is needed. In this study the effect of zinc injection in Hanul unit 1 with a HDCI of around 150 Btu/ft{sup 2}-gal- .deg. F was evaluated. And in the next study the effect of zinc injection in the plant of HDCI of around 200 Btu/ft{sup 2}-gal- .deg. F will be evaluated. Zinc injection had not caused any increase in oxide thickness in Hanul unit 1. Most of the oxide thickness measurement data with zinc injection are well within the non-zinc injection database. And the computer code which was developed based on non-zinc injection database well predicts oxide thickness for fuel rod with zinc injection. Thus, it can be concluded that zinc injection doesn

Shoulder Magnetic Resonance Arthrography: A Prospective Randomized Study of Anterior and Posterior Ultrasonography-Guided Contrast Injections

Energy Technology Data Exchange (ETDEWEB)

Koivikko, M.P.; Mustonen, A.O.T. (Dept. of Radiology, Helsinki Univ. Central Hospital, Helsinki (Finland))

2008-10-15

Background: Magnetic resonance (MR) arthrography is an accurate imaging method for internal shoulder derangements and rotator cuff pathologies. Both anterior and posterior contrast injection techniques, under palpatory, fluoroscopic, or ultrasonographic guidance have been described in the literature. However, clinical comparisons of the injection techniques remain few. Purpose: To compare the performance of anterior and posterior ultrasonography (US)-guided arthrography injections of the shoulder regarding patient discomfort and influence on diagnostic MR reading, and to illustrate the typical artifacts resulting from contrast leakage in the respective techniques. Material and Methods: 43 MR arthrographies were prospectively randomized into anterior and posterior US-guided contrast injections and performed by two radiologists, with the study of artifacts from contrast leakage. Pain from the injections was assessed by a survey utilizing a 100-mm visual analogue scale (VAS). Results: Of the 23 anterior injections, nine caused contrast artifacts in the subscapular tendon, and in three the leakage extended further anteriorly. Of the 20 posterior injections, 12 showed injection artifacts of the rotator cuff, extending outside the cuff in seven. Two of the anterior and none of the posterior artifacts compromised diagnostic quality. In posterior injections, the leakage regularly occurred at the caudal edge of the infraspinatus muscle and was easily distinguishable from rotator cuff tears. All patients completed the pain survey. Mean VAS scores were 25.0 (median 18, SD 22) for anterior, and 25.4 (median 16, SD 25) for posterior injections. The two radiologists achieved different mean VAS scores but closely agreed as to anterior and posterior VAS scores. Conclusion: Arthrography injections were fairly simple to perform under US guidance. Patient discomfort for anterior and posterior injections was equally minor. A tailored approach utilizing anterior or posterior injections

Standard sonography and arthrosonography in the study of rotator cuff tears

International Nuclear Information System (INIS)

El-Dalati, Ghassan; Martone, Enrico; Caffarri, Sabrina; Fusaro, Michele; Pozzi Mucelli, Roberto; Castellarin, Gianluca; Ricci, Matteo; Vecchini, Eugenio

2005-01-01

Purpose. The aim of this study was to evaluate the sensitivity of ultrasonography, integrating standard ultrasound and arthrosonography after injecting a saline solution into the glenohumeral cavity in cases of suspected rotator cuff tears. Materials and methods. We respectively examinated 40 patients awaiting shoulder arthroscopy for suspected or diagnosed tears of the rotator cuff. A radiologist, unaware of the pre-operative diagnosis, performed an ultrasound scan on all the patients before and after the injection of saline solution into the glenohumeral cavity. The parameters considered were presence or absence of a rotator cuff injury; type of injury according to Snyder and its extent along the longitudinal and transverse planes; presence or absence of effusion into the articular cavity; subacromial/subdeltoid bursal distension. All the patients underwent arthroscopy either the same day of the day after the ultrasound examination. Results. Standard sonography showed 26 complete rotator cuff tears (type C according to Snyder), 2 partial tears (type B according to Snyder) and 12 intact rotator cuffs. Arthrosonography detected 31 complete rotator cuff tears (type C according to Snyder), 1 partial tear (type B according to Snyder) and 8 intact rotator cuffs. Arthroscopy identified 32 complete rotator cuff tears (type C according to Snyder), 1 partial tear (type B according to Snyder) and 8 intact rotator cuffs. Analysis of the results shows that, taking arthroscopy as the gold standard, the sensitivity of normal sonography is 81.2%, whereas that of arthosonography is 96.8% (p [it

Refueling system with small diameter rotatable plugs

International Nuclear Information System (INIS)

Ritz, W.C.

1987-01-01

This patent describes a liquid-metal fastbreeder nuclear reactor comprising a reactor pressure vessel and closure head therefor, a reactor core barrel disposed within the reactor vessel and enclosing a reactor core having therein a large number of closely spaced fuel assemblies, and the reactor core barrel and the reactor core having an approximately concentric circular cross-sectional configuration with a geometric center in predetermined location within the reactor vessel. The improved refueling system described here comprises: a large controllably rotatable plug means comprising the substantial portion of the closure head, a reactor upper internals structure mounted from the large rotatable plug means. The large rotatable plug means has an approximately circular configuration which approximates the cross-sectional configuration of the reactor core barrel with a center of rotation positioned a first predetermined distance from the geometric center of the reactor core barrel so that the large rotatable plug means rotates eccentrically with respect to the reactor core barrel; a small controllably rotatable plug means affixed to the large rotatable plug means and rotatable with respect thereto. The small rotatable plug means has a center of rotation which is offset a second predetermined distance from the rotational center of the large rotatable plug means so that the small rotatable plug means rotates eccentrically with respect to the large rotatable plug means

Crushing method for nuclear fuel powder

International Nuclear Information System (INIS)

Hasegawa, Shin-ichi; Tsuchiya, Haruo.

1997-01-01

A crushing medium is contained in mill pots disposed at the circumferential periphery of a main axis. The diameter of each mill pot is determined such that powdery nuclear fuels containing aggregated powders and ground and mixed powders do not reach criticality. A plurality of mill pots are revolved in the direction of the main axis while each pots rotating on its axis. Powdery nuclear fuels containing aggregated powders are conveyed to a supply portion of the moll pot, and an inert gas is supplied to the supply portion. The powdery nuclear fuels are supplied from the supply portion to the inside of the mill pots, and the powdery nuclear fuels containing aggregated powders are crushed by centrifugal force caused by the rotation and the revolving of the mill pots by means of the crushing medium. UO 2 powder in uranium oxide fuels can be crushed continuously. PuO 2 powder and UO 2 powder in MOX fuels can be crushed and mixed continuously. (I.N.)

Aircraft dual-shaft jet engine with indirect action fuel flow controller

Science.gov (United States)

Tudosie, Alexandru-Nicolae

2017-06-01

The paper deals with an aircraft single-jet engine's control system, based on a fuel flow controller. Considering the engine as controlled object and its thrust the most important operation effect, from the multitude of engine's parameters only its rotational speed n is measurable and proportional to its thrust, so engine's speed has become the most important controlled parameter. Engine's control system is based on fuel injection Qi dosage, while the output is engine's speed n. Based on embedded system's main parts' mathematical models, the author has described the system by its block diagram with transfer functions; furthermore, some Simulink-Matlab simulations are performed, concerning embedded system quality (its output parameters time behavior) and, meanwhile, some conclusions concerning engine's parameters mutual influences are revealed. Quantitative determinations are based on author's previous research results and contributions, as well as on existing models (taken from technical literature). The method can be extended for any multi-spool engine, single- or twin-jet.

Modeling and control of fuel distribution in a dual-fuel internal combustion engine leveraging late intake valve closings

Energy Technology Data Exchange (ETDEWEB)

Kassa, Mateos [Mechanical, Materials, and Aerospace Engineering Department, Illinois Institute of Technology, Chicago, IL, USA; Hall, Carrie [Mechanical, Materials, and Aerospace Engineering Department, Illinois Institute of Technology, Chicago, IL, USA; Ickes, Andrew [Fuels, Engine and Aftertreatment Research, Argonne National Laboratory, Argonne, IL, USA; Wallner, Thomas [Fuels, Engine and Aftertreatment Research, Argonne National Laboratory, Argonne, IL, USA

2016-10-07

Advanced internal combustion engines, although generally more efficient than conventional combustion engines, often encounter limitations in multi-cylinder applications due to variations in the combustion process encountered across cylinders and between cycles. This study leverages experimental data from an inline 6-cylinder heavy-duty dual fuel engine equipped with exhaust gas recirculation (EGR), a variable geometry turbocharger, and a fully-flexible variable intake valve actuation system to study cylinder-to-cylinder variations in power production and the underlying uneven fuel distribution that causes these variations. The engine is operated with late intake valve closure timings in a dual-fuel combustion mode in which a high reactivity fuel is directly injected into the cylinders and a low reactivity fuel is port injected into the cylinders. Both dual fuel implementation and late intake valve closing (IVC) timings have been shown to improve thermal efficiency. However, experimental data from this study reveal that when late IVC timings are used on a multi-cylinder dual fuel engine a significant variation in IMEP across cylinders results and as such, leads to efficiency losses. The difference in IMEP between the different cylinders ranges from 9% at an IVC of 570°ATDC to 38% at an IVC of 610°ATDC and indicates an increasingly uneven fuel distribution. These experimental observations along with engine simulation models developed using GT-Power have been used to better understand the distribution of the port injected fuel across cylinders under various operating conditions on such dual fuel engines. This study revealed that the fuel distribution across cylinders in this dual fuel application is significantly affected by changes in the effective compression ratio as determined by the intake valve close timing as well as the design of the intake system (specifically the length of the intake runners). Late intake valve closures allow a portion of the trapped air

Characteristics of spray from a GDI fuel injector for naphtha and surrogate fuels

KAUST Repository

Wang, Libing

2016-11-18

Characterization of the spray angle, penetration, and droplet size distribution is important to analyze the spray and atomization quality. In this paper, the spray structure development and atomization characterization of two naphtha fuels, namely light naphtha (LN) and whole naphtha (WN) and two reference fuel surrogates, i.e. toluene primary reference fuel (TPRF) and primary reference fuel (PRF) were investigated using a gasoline direct injection (GDI) fuel injector. The experimental setup included a fuel injection system, a high-speed imaging system, and a droplet size measurement system. Spray images were taken by using a high-speed camera for spray angle and penetration analysis. Sauter mean diameter, Dv(10), Dv(50), Dv(90), and particle size distribution were measured using a laser diffraction technique. Results show that the injection process is very consistent for different runs and the time averaged spray angles during the measuring period are 103.45°, 102.84°, 102.46° and 107.61° for LN, WN, TPRF and PRF, respectively. The spray front remains relatively flat during the early stage of the fuel injection process. The peak penetration velocities are 80 m/s, 75 m/s, 75 m/s and 79 m/s for LN, WN, TPRF and PRF, respectively. Then velocities decrease until the end of the injection and stay relatively stable. The transient particle size and the time-averaged particle size were also analyzed and discussed. The concentration weighted average value generally shows higher values than the arithmetic average results. The average data for WN is usually the second smallest except for Dv90, of which WN is the biggest. Generally the arithmetic average particle sizes of PRF are usually the smallest, and the sizes does not change much with the measuring locations. For droplet size distribution results, LN and WN show bimodal distributions for all the locations while TPRF and PRF shows both bimodal and single peak distribution patterns. The results imply that droplet size

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.

Spent fuel container alignment device and method

Science.gov (United States)

Jones, Stewart D.; Chapek, George V.

1996-01-01

An alignment device is used with a spent fuel shipping container including a plurality of fuel pockets for spent fuel arranged in an annular array and having a rotatable cover including an access opening therein. The alignment device includes a lightweight plate which is installed over the access opening of the cover. A laser device is mounted on the plate so as to emit a laser beam through a laser admittance window in the cover into the container in the direction of a pre-established target associated with a particular fuel pocket. An indexing arrangement on the container provides an indication of the angular position of the rotatable cover when the laser beam produced by the laser is brought into alignment with the target of the associated fuel pocket.

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.

Optical fuel spray measurements

Energy Technology Data Exchange (ETDEWEB)

Hillamo, H.

2011-07-01

Diesel fuel sprays, including fuel/air mixing and the physics of two-phase jet formation, are discussed in the thesis. The fuel/air mixing strongly affects emissions formation in spray combustion processes where the local combustion conditions dictate the emission formation. This study comprises optical measurements both in pressurized spray test rigs and in a running engine.The studied fuel injection was arranged with a common rail injection system and the injectors were operated with a solenoid-based injection valve. Both marine and heavy-duty diesel engine injectors were used in the study. Optical fuel spray measurements were carried out with a laser-based double-framing camera system. This kind of equipments is usually used for flow field measurements with Particle Image Velocimetry technique (PIV) as well as for backlight imaging. Fundamental fuel spray properties and spray formation were studied in spray test rigs. These measurements involved studies of mixing, atomization, and the flow field. Test rig measurements were used to study the effect of individual injection parameters and component designs. Measurements of the fuel spray flow field, spray penetration, spray tip velocity, spray angle, spray structure, droplet accumulation, and droplet size estimates are shown. Measurement campaign in a running optically accessible large-bore medium-speed engine was also carried out. The results from engine tests were compared with equivalent test rig measurements, as well as computational results, to evaluate the level of understanding of sprays. It was shown that transient spray has an acceleration and a deceleration phase. Successive flow field measurements (PIV) in optically dense diesel spray resulted in local and average velocity data of diesel sprays. Processing fuel spray generates a flow field to surrounding gas and entrainment of surrounding gas into fuel jet was also seen at the sides of the spray. Laser sheet imaging revealed the inner structure of diesel

PENGARUH TEMPERATUR SOLAR TERHADAP PERFORMA MESIN DIESEL DIRECK INJECTION PUTARAN KONSTAN

Directory of Open Access Journals (Sweden)

Murni Murni

2012-07-01

Full Text Available The imperfect combustion process will be a problem in the development effort of diesel engine’s performance.Nonhomogen air–fuel mixing process is one of the factors which cause the imperfect combustion.By heating upthe diesel solar up to a certain temperature before it goes through the high pressure injection pump will lowerits density and viscosity. Therefore, when injected in the combustion chamber, it will formed smaller droplets offuel spray which result in a more homogenious air–fuel mixture. Also by using higher temperature will make thediesel fuel easier to ignite in order to compensate the limited time which is available in high speed operatingconditions. Diesel engine Dong Feng 1 cylinder direct injection at constant speed was used in this research. Thefuel used are solar with temperature variations in the range from 30oC to 70oC . The best thermal efficiency forsolar fuel is 30 % at 60oC with 28 % BSFC. In this condition, the fuel consumption was decreased 4 % bycomparing with that at 30oC.

Servo-driven piezo common rail diesel injection system; Servogetriebene Piezo-Common-Rail-Dieseleinspritzung

Energy Technology Data Exchange (ETDEWEB)

Schoeppe, Detlev; Stahl, Christian; Krueger, Grit; Dian, Vincent [Continental Automotive GmbH, Regensburg (Germany). Geschaeftsbereich Engine Systems

2012-03-15

The requirements to be met by future diesel engines represent major challenges for fuel injection technology: Fuel consumption, emissions and noise development are to be further reduced without impairing driving enjoyment. To address these challenges, Continental has developed a new fuel injection system that features a high level of precision and accuracy. The key component is a servo-driven injector that is operated in a closed control circuit. (orig.)

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.

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.

Performance and emission studies on port injection of hydrogen with varied flow rates with Diesel as an ignition source

International Nuclear Information System (INIS)

Saravanan, N.; Nagarajan, G.

2010-01-01

Automobiles are one of the major sources of air pollution in the environment. In addition CO 2 emission, a product of complete combustion also has become a serious issue due to global warming effect. Hence the search for cleaner alternative fuels has become mandatory. Hydrogen is expected to be one of the most important fuels in the near future for solving the problems of air pollution and greenhouse gas problems (carbon dioxide), thereby protecting the environment. Hence in the present work, an experimental investigation has been carried out using hydrogen in the dual fuel mode in a Diesel engine system. In the study, a Diesel engine was converted into a dual fuel engine and hydrogen fuel was injected into the intake port while Diesel was injected directly inside the combustion chamber during the compression stroke. Diesel injected inside the combustion chamber will undergo combustion first which in-turn would ignite the hydrogen that will also assist the Diesel combustion. Using electronic control unit (ECU), the injection timings and injection durations were varied for hydrogen injection while for Diesel the injection timing was 23 o crank angle (CA) before injection top dead centre (BITDC). Based on the performance, combustion and emission characteristics, the optimized injection timing was found to be 5 o CA before gas exchange top dead centre (BGTDC) with injection duration of 30 o CA for hydrogen Diesel dual fuel operation. The optimum hydrogen flow rate was found to be 7.5 lpm. Results indicate that the brake thermal efficiency in hydrogen Diesel dual fuel operation increases by 15% compared to Diesel fuel at 75% load. The NO X emissions were higher by 1-2% in dual fuel operation at full load compared to Diesel. Smoke emissions are lower in the entire load spectra due to the absence of carbon in hydrogen fuel. The carbon monoxide (CO), carbon dioxide (CO 2 ) emissions were lesser in hydrogen Diesel dual fuel operation compared to Diesel. The use of hydrogen

Performance and emission studies on port injection of hydrogen with varied flow rates with Diesel as an ignition source

Energy Technology Data Exchange (ETDEWEB)

Saravanan, N. [ERC Engines, Tata Motors, Pimpri, Pune (India); Nagarajan, G. [Internal Combustion Engineering Division, Department of Mechanical Engineering, College of Engineering, Guindy, Anna University, Chennai (India)

2010-07-15

Automobiles are one of the major sources of air pollution in the environment. In addition CO{sub 2} emission, a product of complete combustion also has become a serious issue due to global warming effect. Hence the search for cleaner alternative fuels has become mandatory. Hydrogen is expected to be one of the most important fuels in the near future for solving the problems of air pollution and greenhouse gas problems (carbon dioxide), thereby protecting the environment. Hence in the present work, an experimental investigation has been carried out using hydrogen in the dual fuel mode in a Diesel engine system. In the study, a Diesel engine was converted into a dual fuel engine and hydrogen fuel was injected into the intake port while Diesel was injected directly inside the combustion chamber during the compression stroke. Diesel injected inside the combustion chamber will undergo combustion first which in-turn would ignite the hydrogen that will also assist the Diesel combustion. Using electronic control unit (ECU), the injection timings and injection durations were varied for hydrogen injection while for Diesel the injection timing was 23 crank angle (CA) before injection top dead centre (BITDC). Based on the performance, combustion and emission characteristics, the optimized injection timing was found to be 5 CA before gas exchange top dead centre (BGTDC) with injection duration of 30 CA for hydrogen Diesel dual fuel operation. The optimum hydrogen flow rate was found to be 7.5 lpm. Results indicate that the brake thermal efficiency in hydrogen Diesel dual fuel operation increases by 15% compared to Diesel fuel at 75% load. The NO{sub X} emissions were higher by 1-2% in dual fuel operation at full load compared to Diesel. Smoke emissions are lower in the entire load spectra due to the absence of carbon in hydrogen fuel. The carbon monoxide (CO), carbon dioxide (CO{sub 2}) emissions were lesser in hydrogen Diesel dual fuel operation compared to Diesel. The use of

Bioethanol E85 as a fuel for dual fuel diesel engine

International Nuclear Information System (INIS)

Tutak, Wojciech

2014-01-01

Highlights: • An increase in the E85 fraction is changing the nature of the HRR course. • Change of combustion phasing with E85 fraction. • The ignition delay of dual fuel engine decreases with increasing E85 fuel. • Premixed combustion of E85 fuel reduces smoke emissions. - Abstract: This study investigates the potential of E85 fuelling in a diesel engine. Researches were performed using a three-cylinder a direct injection diesel engine. A dual-fuelling technology is implemented such that E85 is introduced into the intake manifold using a port-fuel injector while diesel is injected directly into the cylinder. The primary aim of the study was to determine the operating parameters of the engine powered on E85 bioethanol fuel in dual fuel system. The parameters that were taken into account are: engine efficiency, indicated mean effective pressure, heat release rate, combustion duration and ignition delay, combustion phasing and exhaust toxicity. With E85 fuel participation, NO x and soot emissions were reduced, whereas CO and HC emissions increased considerably. It was found that E85 participation in a combustible mixture reduced the excess air factor for the engine and this led to increased emissions of CO and HC, but decreased emissions of nitrogen oxides and soot

Analysis of toroidal rotation data for the DIII-D tokamak

International Nuclear Information System (INIS)

St John, H.; Stroth, U.; Burrell, K.H.; Groebner, R.J.; DeBoo, J.C.; Gohil, P.

1989-01-01

Both poloidal and toroidal rotation are observed during routine neutral beam heating operation of the DIII-D tokamak. Poloidal rotation results and the empirical techniques used to measure toroidal and poloidal rotation speeds are described by Groebner. Here we concentrate on the analysis of recent measurements of toroidal rotation made during diverted, H-mode operation of the DIII-D tokamak during co- and counter-neutral beam injection of hydrogen into deuterium plasmas. Our results are based on numerical inversions using the transport code ONETWO, modified to account for the radial diffusion of toroidal angular momentum. 13 refs., 4 figs

Effects of diluent admissions and intake air temperature in exhaust gas recirculation on the emissions of an indirect injection dual fuel engine

Energy Technology Data Exchange (ETDEWEB)

Abd-Alla, G.H.; Soliman, H.A.; Badr, O.A.; Abd-Rabbo, M.F. [Zagazig University, Cairo (Egypt). Shoubra Faculty of Engineering

2001-05-01

The operation of Diesel engines on gaseous fuels, commonly known as dual fuel engines, uses Diesel fuel as the pilot fuel and gaseous fuel (methane and sometimes propane in the present work) as the main fuel. The gaseous fuel was inducted in the intake manifold to mix with the intake air. The investigation was conducted on a high speed indirect injection (Ricardo-E6) dual fuel engine and was concerned with the effects of exhaust gas recirculation (EGR) on the dual fuel engine combustion and emissions, in particular, the effects of intake air temperature and diluent admissions (N{sub 2} and CO{sub 2}) on combustion and emissions. The use of diluents to displace oxygen (O{sub 2}) in the intake air resulted in a reduction in the O{sub 2} supplied to the engine, increased the inlet charge thermal capacity (thermal effect) and, potentially, CO{sub 2} and N{sub 2} participated in the combustion process (chemical effect). In a separate series of tests, the temperature of the engine inlet charge was raised gradually in order to simulate the effect of mixing hot EGR with the engine inlet gaseous fuel air mixture. It was found that the admission of diluents resulted in reductions in the exhaust oxides of nitrogen (NO{sub x}). Higher inlet charge temperature increases the exhaust NO{sub x} but reduces the unburned hydrocarbon emissions. Finally, when carbon dioxide was added to the inlet gaseous fuel air charge, large reductions in NO{sub x} were observed. (author)

Monte-Carlo calculation of perpendicular neutral-beam injection in helical systems

International Nuclear Information System (INIS)

Hanatani, K.; Wakatani, M.; Uo, K.

1981-01-01

The effect of a helical field ripple on the slowing-down process of the fast ions created by neutral injection is investigated numerically. For this purpose, the guiding-centre orbits are followed in a model magnetic field without plasma current, on the assumption that the slowing-down process is to be classical. Optimum injection angles in two types of helical magnetic traps are compared. One is the Heliotron-E configuration with a large rotational transform and deep helical ripple; the other one is the conventional stellarator field with a small rotational transform and shallow helical ripple. In contrast to the stellarator, the heating efficiency as calculated for Heliotron-E does not decrease monotonically when the injection angle is perpendicular to the toroidal direction; a heating efficiency of above 70% was obtained for perpendicular injection into a high-density plasma with negligible charge-exchange loss. The difference in heating efficiency versus injection angle between heliotron and conventional stellarator fields is explained by a difference in drift motion of the helically trapped fast ions. (author)

Autoignition of liquid-fuel sprays

International Nuclear Information System (INIS)

Mitzutani, Y.

1991-01-01

This paper reports on the published autoignition data of liquid fuel sprays that were extensively reviewed by classifying them into the following three categories; liquid fuels injected into a stagnant hot atmosphere, liquid fuels injected into a hot air stream (vitiated or unvitiated), and droplet cluster ignited behind an incident or reflected shock. Comparison of these data with the counterparts of gaseous fuels and single droplets revealed that it was the ignition process dominated by droplet evaporation whereas it was the one dominated by chemical kinetics. It consisted, depending on the experimental condition, of the data and of the ignition process dominated by the shattering of droplets by an incident shock. In addition, theoretical works on spray autoignition were reviewed, pointing out that they were still far from universally predicting the ignition delays of liquid fuel sprays

Premixed direct injection nozzle

Science.gov (United States)

Zuo, Baifang [Simpsonville, SC; Johnson, Thomas Edward [Greer, SC; Lacy, Benjamin Paul [Greer, SC; Ziminsky, Willy Steve [Simpsonville, SC

2011-02-15

An injection nozzle having a main body portion with an outer peripheral wall is disclosed. The nozzle includes a plurality of fuel/air mixing tubes disposed within the main body portion and a fuel flow passage fluidly connected to the plurality of fuel/air mixing tubes. Fuel and air are partially premixed inside the plurality of the tubes. A second body portion, having an outer peripheral wall extending between a first end and an opposite second end, is connected to the main body portion. The partially premixed fuel and air mixture from the first body portion gets further mixed inside the second body portion. The second body portion converges from the first end toward said second end. The second body portion also includes cooling passages that extend along all the walls around the second body to provide thermal damage resistance for occasional flame flash back into the second body.

Ultrasound-guided subacromial injections of sodium hyaluronate for the management of rotator cuff tendinopathy: a prospective comparative study with rehabilitation therapy.

Science.gov (United States)

Merolla, G; Bianchi, P; Porcellini, G

2013-06-01

Rotator cuff (RC) tendinopathy is a common cause of pain and shoulder dysfunction. The literature evidence suggests that a combination of overuse and extrinsic compression may induce chronic RC tendinopathy. Aim of the current study was to compare the results of subacromial sodium hyaluronate injections with rehabilitation therapy. We enrolled 48 patients (M/F: 26/22; mean age: 50 years; shoulder right/left: 29/19) with persistent shoulder pain for at least 4 months. Exclusion criteria were as follows: RC tear, calcifying tendinitis, glenohumeral instability, osteoarthritis, rheumatic diseases, physical therapy and/or injection in the previous 4 months, shoulder surgery, anesthetic nerve block, trauma, and severe medical diseases. The included subjects received either two ultrasound-guided subacromial hyaluronic acid (HA) injections (25 patients, HA group) at baseline and 14 days, or underwent rehabilitation therapy (23 patients, Physio group) including active shoulder mobilization, soft tissue stretching and humeral head positioner and propeller muscles strengthening for 30 days (3 sessions every week). Clinical assessment of shoulder function was performed with visual analog scale score for pain (0-100), Oxford Shoulder Score (OSS), and Constant-Murley Score (CS). Overall, patients were examined at baseline, week 2, week 4, week 12, and week 24. Statistical significance was set at 5 % (p  0.05), week 12 (p > 0.05), and week 24 (p > 0.05). CS and OSS in the HA group increased significantly at week 2 (p  0.05). A significant improvement of CS and OSS we found in the Physio group at week 2 (p  0.05). Subacromial HA injections could be an effective and safe alternative treatment for patients suffering from RC tendinopathy. We believe that the results of this study are encouraging but not lasting and we might suppose that a series of three to four subacromial sodium hyaluronate injections could provide good mid- and long-term clinical benefits.

Development of ceramic roller bush for diesel fuel injection pump; Nenryo funsha pump yo ceramics sei roller bush no kaihatsu

Energy Technology Data Exchange (ETDEWEB)

Noda, K; Kamiya, S; Fujimura, M; Tsuzuki, M [Toyota Motor Corp., Aichi (Japan); Taniguchi, K [Denso Corp., Aichi (Japan)

1997-10-01

Silicon nitride ceramics have been applied to roller bush for diesel fuel injection pump in order to improve the seizure resistance. It was found that ceramic roller bush made it possible to improve the seizure load by more than three times as compared to conventional metal roller bush when the kerosene was used as lubricant The ceramic roller bush proved to be durable under engine operating conditions. 6 refs., 13 figs., 1 tab.

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)

Review of the Conceptual Design for In-Vessel Fuel Handling Machines in SFR

International Nuclear Information System (INIS)

Kim, S. H.; Koo, G. H.

2012-01-01

The main in-vessel fuel handling machines in sodium cooled fast reactor(SFR) are composed of the in-vessel transfer machine(IVTM) and the rotating plug. These machines perform the function to handle fuel assemblies inside the reactor core during the refueling time. The IVTM should be able to access all areas above the reactor core and the fuel transfer port which can discharge the fuel assembly by the rotation of the rotating plug. In the 600 MWe demonstration reactor, the conceptual design of the in-vessel fuel handling machines was carried out. As shown in Fig. 1, the invessel fuel handling machines of the demonstration reactor are the double rotating plug type. With reference to the given core configuration of the demonstration reactor, the arrangement design of the rotating plug was carried out by using the developed simulation program. At present, the conceptual design of SFR prototype reactor which has small capacity of about 100 MWe is being started. Thus, it is necessary the economical efficiency and the reliability of the in-vessel fuel handling machines are reviewed according to the reduction of the power capacity. In this study, the preliminary design concepts of the main invessel fuel handling machines according to the fuel handling type are compared. Also, the design characteristics for the driving mechanism of the IVTM in the demonstration reactor and the recovery concept from the malfunction are reviewed