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Sample records for chemical engineering combustion

  1. Chemical Kinetic Models for Advanced Engine Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Pitz, William J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Mehl, Marco [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Westbrook, Charles K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2014-10-22

    The objectives for this project are as follows: Develop detailed chemical kinetic models for fuel components used in surrogate fuels for compression ignition (CI), homogeneous charge compression ignition (HCCI) and reactivity-controlled compression-ignition (RCCI) engines; and Combine component models into surrogate fuel models to represent real transportation fuels. Use them to model low-temperature combustion strategies in HCCI, RCCI, and CI engines that lead to low emissions and high efficiency.

  2. Combustion in Homogeneous Charge Compression Ignition Engines: Experiments and Detailed Chemical Kinetic Simulations

    Energy Technology Data Exchange (ETDEWEB)

    Flowers, D L

    2002-06-07

    Homogeneous charge compression ignition (HCCI) engines are being considered as an alternative to diesel engines. The HCCI concept involves premixing fuel and air prior to induction into the cylinder (as is done in current spark-ignition engine) then igniting the fuel-air mixture through the compression process (as is done in current diesel engines). The combustion occurring in an HCCI engine is fundamentally different from a spark-ignition or Diesel engine in that the heat release occurs as a global autoignition process, as opposed to the turbulent flame propagation or mixing controlled combustion used in current engines. The advantage of this global autoignition is that the temperatures within the cylinder are uniformly low, yielding very low emissions of oxides of nitrogen (NO{sub x}, the chief precursors to photochemical smog). The inherent features of HCCI combustion allows for design of engines with efficiency comparable to, or potentially higher than, diesel engines. While HCCI engines have great potential, several technical barriers exist which currently prevent widespread commercialization of this technology. The most significant challenge is that the combustion timing cannot be controlled by typical in-cylinder means. Means of controlling combustion have been demonstrated, but a robust control methodology that is applicable to the entire range of operation has yet to be developed. This research focuses on understanding basic characteristics of controlling and operating HCCI engines. Experiments and detailed chemical kinetic simulations have been applied to the characterize some of the fundamental operational and design characteristics of HCCI engines. Experiments have been conducted on single and multi-cylinder engines to investigate general features of how combustion timing affects the performance and emissions of HCCI engines. Single-zone modeling has been used to characterize and compare the implementation of different control strategies. Multi

  3. Quasi-Dimensional Modeling of a CNG Fueled HCCI Engine Combustion Using Detailed Chemical Kinetic

    Directory of Open Access Journals (Sweden)

    Younes Bakhshan

    2013-01-01

    Full Text Available In this study, an in-house quasi dimensional code has been developed which simulates the intake, compression, combustion, expansion and exhaust strokes of a homogeneous charge compression ignition (HCCI engine. The compressed natural gas (CNG has been used as fuel. A detailed chemical kinetic scheme constituting of 310 and 1701 elementary equations developed by Bakhshan et al. has been applied for combustion modeling and heat release calculations. The zero-dimensional k-ε turbulence model has been used for calculation of heat transfer. The output results are the performance and pollutants emission and combustion characteristics in HCCI engines. Parametric studies have been conducted to discussing the effects of various parameters on performance and pollutants emission of these engines.

  4. Process/Engineering Co-Simulation of Oxy-Combustion and Chemical Looping Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Sloan, David [Alstom Power Inc., Windsor, CT (United States)

    2013-03-01

    Over the past several years, the DOE has sponsored various funded programs, collectively referred to as Advanced Process Engineering Co-Simulator (APECS) programs, which have targeted the development of a steady-state simulator for advanced power plants. The simulator allows the DOE and its contractors to systematically evaluate various power plant concepts, either for preliminary conceptual design or detailed final design.

  5. Low Temperature Combustion with Thermo-Chemical Recuperation to Maximize In-Use Engine Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Nigel N. Clark; Francisco Posada; Clinton Bedick; John Pratapas; Aleksandr Kozlov; Martin Linck; Dmitri Boulanov

    2009-03-30

    The key to overcome Low Temperature Combustion (LTC) load range limitations in reciprocating engines is based on proper control over the thermo-chemical properties of the in-cylinder charge. The studied alternative to achieve the required control of LTC is the use of two separate fuel streams to regulate timing and heat release at specific operational points, where the secondary fuel is a reformed product of the primary fuel in the tank. It is proposed in this report that the secondary fuel can be produced using exhaust heat and Thermo-Chemical Recuperation (TCR). TCR for reciprocating engines is a system that employs high efficiency recovery of sensible heat from engine exhaust gas and uses this energy to transform fuel composition. The recuperated sensible heat is returned to the engine as chemical energy. Chemical conversions are accomplished through catalytic and endothermic reactions in a specially designed reforming reactor. An equilibrium model developed by Gas Technology Institute (GTI) for heptane steam reforming was applied to estimate reformed fuel composition at different reforming temperatures. Laboratory results, at a steam/heptane mole ratio less than 2:1, confirm that low temperature reforming reactions, in the range of 550 K to 650 K, can produce 10-30% hydrogen (by volume, wet) in the product stream. Also, the effect of trading low mean effective pressure for displacement to achieve power output and energy efficiency has been explored by WVU. A zerodimensional model of LTC using heptane as fuel and a diesel Compression Ignition (CI) combustion model were employed to estimate pressure, temperature and total heat release as inputs for a mechanical and thermal loss model. The model results show that the total cooling burden on an LTC engine with lower power density and higher displacement was 14.3% lower than the diesel engine for the same amount of energy addition in the case of high load (43.57mg fuel/cycle). These preliminary modeling and

  6. Models of Non-Stationary Thermodynamic Processes in Rocket Engines Taking into Account a Chemical Equilibrium of Combustion Products

    Directory of Open Access Journals (Sweden)

    A. V. Aliev

    2015-01-01

    Full Text Available The paper considers the two approach-based techniques for calculating the non-stationary intra-chamber processes in solid-propellant rocket engine (SPRE. The first approach assumes that the combustion products are a mechanical mix while the other one supposes it to be the mix, which is in chemical equilibrium. To enhance reliability of solution of the intra ballistic tasks, which assume a chemical equilibrium of combustion products, the computing algorithms to calculate a structure of the combustion products are changed. The algorithm for solving a system of the nonlinear equations of chemical equilibrium, when determining the iterative amendments, uses the orthogonal QR method instead of a method of Gauss. Besides, a possibility to apply genetic algorithms in a task about a structure of combustion products is considered.It is shown that in the tasks concerning the prediction of non-stationary intra ballistic characteristics in a solid propellant rocket engine, application of models of mechanical mix and chemically equilibrium structure of combustion products leads to qualitatively and quantitatively coinciding results. The maximum difference in parameters is 5-10%, at most. In tasks concerning the starting operation of a solid sustainer engine with high-temperature products of combustion difference in results is more essential, and can reach 20% and more.A technique to calculate the intra ballistic parameters, in which flotation of combustion products is considered in the light of a spatial statement, requires using the high-performance computer facilities. For these tasks it is offered to define structure of products of combustion and its thermo-physical characteristics, using the polynoms coefficients of which should be predefined.

  7. Internal combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Helmich, M.J.; Hoagland, M.C.; Hubbard, R.L.; Schaub, F.S.

    1981-12-22

    A method of combusting natural gas fuel in a two cycle, turbocharged internal combustion engine substantially reduces the production of nitrogen-oxygen emissions. An improved turbocharger design provides increased air charging pressure, produces a controlled lean air/fuel mixture and lowers peak combustion temperatures. A jet cell ignition device ensures uniform, reliable ignition of the lean air/fuel mixture under all operating conditions and the lean air/fuel mixture in turn encourages complete fuel combustion and provides excellent combustion characteristics with methane, ethane and heavier paraffinic hydrocarbon fuels. These structural modifications and adjustment of other operating parameters combine to reduce nitric oxide (NO) and nitrogen dioxide (NO/sub 2/) emissions by as much as 75% while effecting only a negligible increase in fuel consumption.

  8. Internal combustion piston engines

    Energy Technology Data Exchange (ETDEWEB)

    Segaser, C.L.

    1977-07-01

    Current worldwide production of internal combustion piston engines includes many diversified types of designs and a very broad range of sizes. Engine sizes range from a few horsepower in small mobile units to over 40,000 brake horsepower in large stationary and marine units. The key characteristics of internal combustion piston engines considered appropriate for use as prime movers in Integrated Community Energy Systems (ICES) are evaluated. The categories of engines considered include spark-ignition gas engines, compression-ignition oil (diesel) engines, and dual-fuel engines. The engines are evaluated with respect to full-load and part-load performance characteristics, reliability, environmental concerns, estimated 1976 cost data, and current and future status of development. The largest internal combustion piston engines manufactured in the United States range up to 13,540 rated brake horsepower. Future development efforts are anticipated to result in a 20 to 25% increase in brake horsepower without increase in or loss of weight, economy, reliability, or life expectancy, predicated on a simple extension of current development trends.

  9. Internal combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Williams, G.J.

    1986-06-03

    A variable power internal combustion engine is described which consists of: a separate air compressor for receiving and compressing a flow of air to a given pressure, the compressor having an inlet valve introducing a flow of air into the compressor and an outlet valve for exhausting compressed air out of the compressor into a compressed air storage means, at least one expander having a cylinder, a cylinder head closing an end of the cylinder, a piston reciprocally mounted in the cylinder for movement away from the cylinder head in a power stroke from an initial position defining a combustion chamber within the cylinder between the cylinder head and the piston, the compressed air storage means receiving the pressurized flow of air from the compressor and being of a volume adequate to provide compressed air in the combustion chamber essentially at the given pressure essentially over the power output of the engine, means for introducing an amount of combustible fuel in the compressed charge to be present with compressed air in the combustion chamber and providing combustion of the amount of fuel in the cylinder with the inlet and exhaust valves closed, cam shaft means in contact with the piston for absorbing and storing the energy of the power stroke of the piston and controlling movement of the piston within the cylinder during the exhaust stroke; the means for varying the volume of the combustion chamber being controlled in accordance with power requirements to provide variable power output and improved efficiency of the engine at power outputs reduced relative to a given design power output of the engine by providing a variable expansion ratio of a minimum of at least about 30 to 1 at the given design power output and higher with reduced power output.

  10. Combustion science and engineering

    CERN Document Server

    Annamalai, Kalyan

    2006-01-01

    Introduction and Review of Thermodynamics Introduction Combustion Terminology Matter and Its Properties Microscopic Overview of Thermodynamics Conservation of Mass and Energy and the First Law of Thermodynamics The Second Law of Thermodynamics Summary Stoichiometry and Thermochemistry of Reacting Systems Introduction Overall Reactions Gas Analyses Global Conservation Equations for Reacting Systems Thermochemistry Summary Appendix Reaction Direction and Equilibrium Introduction Reaction Direction and Chemical Equilibrium Chemical Equilibrium Relations Vant Hoff Equation Adi

  11. Internal Combustion Engines as Fluidized Bed Reactors

    Science.gov (United States)

    Lavich, Zoe; Taie, Zachary; Menon, Shyam; Beckwith, Walter; Daly, Shane; Halliday, Devin; Hagen, Christopher

    2016-11-01

    Using an internal combustion engine as a chemical reactor could provide high throughput, high chemical conversion efficiency, and reactant/product handling benefits. For processes requiring a solid catalyst, the ability to develop a fluidized bed within the engine cylinder would allow efficient processing of large volumes of fluid. This work examines the fluidization behavior of particles in a cylinder of an internal combustion engine at various engine speeds. For 40 micron silica gel particles in a modified Megatech Mark III transparent combustion engine, calculations indicate that a maximum engine speed of about 60.8 RPM would result in fluidization. At higher speeds, the fluidization behavior is expected to deteriorate. Experiments gave qualitative confirmation of the analytical predictions, as a speed of 48 RPM resulted in fluidized behavior, while a speed of 171 RPM did not. The investigation shows that under certain conditions a fluidized bed can be obtained within an engine cylinder. Corresponding Author.

  12. Internal combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Laskaris, M.A.; Broitman, K.; Natale, S.E.

    1991-08-27

    This patent describes improvement in a two-stroke internal combustion engine adapted to run on a diesel or a kerosene type of fuel, and including a piston connected to the crankshaft of the engine to move within a cylinder through a first stroke from a top dead center position to a bottom dead center position and through a second stroke from the bottom dead center position back to the top dead center position. The improvement comprises: means providing a cylinder head at the top end of the engine cylinder in the shape of an open bowl having a generally cup-shaped configuration including a sidewall portion, a spark plug positioned centrally within the bowl at the top end of the cylinder, and means for injecting fuel into the top end of the engine cylinder at a location between the spark plug and the sidewall portion, the fuel injecting means including an injection nozzle having a plurality of nozzle openings therein, the nozzle openings being constructed and arranged to discharge a plurality of plume-like sprays into the top end of the cylinder at a location within the bowl, two of the sprays being directed from the nozzle to diverge and pass along opposite sides of the spark plug, and additional sprays being directed from the nozzle against the sidewall portion or the cylinder head to be deflected therefrom back toward the piston and the spark plug to thereby form a cloud of fuel over the spark plug for good ignition.

  13. Rotary internal combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Witkowski, J.

    1989-12-05

    This patent describes an internal combustion engine assembly. It includes: a central rotor means formed with at least one peripheral fuel cavity. The cavity having a first surface defining a thrust surface and a second surface defining a contoured surface; a housing means enclosing the rotor and having an internal wall encircling the rotor. The internal wall being intercepted by at least two recesses defining cylinder means. The housing means and the rotor means being relatively rotatable; piston means individual to each the cylinder means and reciprocable therein; each piton means having a working face complementary to aid contoured surface; and power means for urging the working face into intimate areal contact with the contoured surface to create a first seal means. The housing means having at lest one fuel inlet port, at least one fuel ignition means and at least one exhaust port whereby during the course of a revolution of the rotor means relative to the housing means, the first seal means, the power means, the respective ports, the ignition means and the fuel cavity cooperate to develop fuel compression, fuel ignition and exhaust functions.

  14. Chemical Kinetic Models for HCCI and Diesel Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Pitz, W J; Westbrook, C K; Mehl, M; Sarathy, S M

    2010-11-15

    Predictive engine simulation models are needed to make rapid progress towards DOE's goals of increasing combustion engine efficiency and reducing pollutant emissions. These engine simulation models require chemical kinetic submodels to allow the prediction of the effect of fuel composition on engine performance and emissions. Chemical kinetic models for conventional and next-generation transportation fuels need to be developed so that engine simulation tools can predict fuel effects. The objectives are to: (1) Develop detailed chemical kinetic models for fuel components used in surrogate fuels for diesel and HCCI engines; (2) Develop surrogate fuel models to represent real fuels and model low temperature combustion strategies in HCCI and diesel engines that lead to low emissions and high efficiency; and (3) Characterize the role of fuel composition on low temperature combustion modes of advanced combustion engines.

  15. Application of a Genetic Algorithm to the Optimization of Rate Constants in Chemical Kinetic Models for Combustion Simulation of HCCI Engines

    Science.gov (United States)

    Kim, Sang-Kyu; Ito, Kazuma; Yoshihara, Daisuke; Wakisaka, Tomoyuki

    For numerically predicting the combustion processes in homogeneous charge compression ignition (HCCI) engines, practical chemical kinetic models have been explored. A genetic algorithm (GA) has been applied to the optimization of the rate constants in detailed chemical kinetic models, and a detailed kinetic model (592 reactions) for gasoline reference fuels with arbitrary octane number between 60 and 100 has been obtained from the detailed reaction schemes for iso-octane and n-heptane proposed by Golovitchev. The ignition timing in a gasoline HCCI engine has been predicted reasonably well by zero-dimensional simulation using the CHEMKIN code with this detailed kinetic model. An original reduced reaction scheme (45 reactions) for dimethyl ether (DME) has been derived from Curran’s detailed scheme, and the combustion process in a DME HCCI engine has been predicted reasonably well in a practical computation time by three-dimensional simulation using the authors’ GTT code, which has been linked to the CHEMKIN subroutines with the proposed reaction scheme and also has adopted a modified eddy dissipation combustion model.

  16. Staged combustion with piston engine and turbine engine supercharger

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Larry E. (Los Gatos, CA); Anderson, Brian L. (Lodi, CA); O' Brien, Kevin C. (San Ramon, CA)

    2011-11-01

    A combustion engine method and system provides increased fuel efficiency and reduces polluting exhaust emissions by burning fuel in a two-stage combustion system. Fuel is combusted in a piston engine in a first stage producing piston engine exhaust gases. Fuel contained in the piston engine exhaust gases is combusted in a second stage turbine engine. Turbine engine exhaust gases are used to supercharge the piston engine.

  17. Free Energy and Internal Combustion Engine Cycles

    CERN Document Server

    Harris, William D

    2012-01-01

    The performance of one type (Carnot) of Internal Combustion Engine (ICE) cycle is analyzed within the framework of thermodynamic free energies. ICE performance is different from that of an External Combustion Engine (ECE) which is dictated by Carnot's rule.

  18. ABB Combustion Engineering nuclear technology

    Energy Technology Data Exchange (ETDEWEB)

    Matzie, R.A.

    1994-12-31

    The activities of ABB Combustion Engineering in the design and construction of nuclear systems and components are briefly reviewed. ABB Construction Engineering continues to improve the design and design process for nuclear generating stations. Potential improvements are evaluated to meet new requirements both of the public and the regulator, so that the designs meet the highest standards worldwide. Advancements necessary to meet market needs and to ensure the highest level of performance in the future will be made.

  19. Chemical kinetics and combustion modeling

    Energy Technology Data Exchange (ETDEWEB)

    Miller, J.A. [Sandia National Laboratories, Livermore, CA (United States)

    1993-12-01

    The goal of this program is to gain qualitative insight into how pollutants are formed in combustion systems and to develop quantitative mathematical models to predict their formation rates. The approach is an integrated one, combining low-pressure flame experiments, chemical kinetics modeling, theory, and kinetics experiments to gain as clear a picture as possible of the process in question. These efforts are focused on problems involved with the nitrogen chemistry of combustion systems and on the formation of soot and PAH in flames.

  20. Investigation of Spark Ignition and Autoignition in Methane and Air Using Computational Fluid Dynamics and Chemical Reaction Kinetics. A numerical Study of Ignition Processes in Internal Combustion Engines

    Energy Technology Data Exchange (ETDEWEB)

    Nordrik, R.

    1993-12-01

    The processes in the combustion chamber of internal combustion engines have received increased attention in recent years because their efficiencies are important both economically and environmentally. This doctoral thesis studies the ignition phenomena by means of numerical simulation methods. The fundamental physical relations include flow field conservation equations, thermodynamics, chemical reaction kinetics, transport properties and spark modelling. Special attention is given to the inclusion of chemical kinetics in the flow field equations. Using his No Transport of Radicals Concept method, the author reduces the computational efforts by neglecting the transport of selected intermediate species. The method is validated by comparison with flame propagation data. A computational method is described and used to simulate spark ignition in laminar premixed methane-air mixtures and the autoignition process of a methane bubble surrounded by hot air. The spark ignition simulation agrees well with experimental results from the literature. The autoignition simulation identifies the importance of diffusive and chemical processes acting together. The ignition delay times exceed the experimental values found in the literature for premixed ignition delay, presumably because of the mixing process and lack of information on low temperature reactions in the skeletal kinetic mechanism. Transient turbulent methane jet autoignition is simulated by means of the KIVA-II code. Turbulent combustion is modelled by the Eddy Dissipation Concept. 90 refs., 81 figs., 3 tabs.

  1. Combustion Engines Development Mixture Formation, Combustion, Emissions and Simulation

    CERN Document Server

    Schwarz, Christian; Teichmann, Rüdiger

    2012-01-01

    In the development of engines and vehicles it is nowadays standard practice to use commercially available computing programmes for simulation, not only of the transient reaction of vehicles or of the complete driveshaft, but also of the highly unsteady processes in the combustion chamber of an engine. Normally the source code is not available for these computing programmes and it takes too much time to study the respective specifications, so the users often do not have sufficient knowledge about the physical and chemical contents of the approaches that the programmes are based on. We have often been faced with this fact in talks to employees or in discussions during the presentation of results of simulation. Therefore it is our aim to point out different physical and chemical approaches and to show the possibilities and limits of the models used.

  2. Chemical Kinetic Modeling of Biofuel Combustion

    Science.gov (United States)

    Sarathy, Subram Maniam

    Bioalcohols, such as bioethanol and biobutanol, are suitable replacements for gasoline, while biodiesel can replace petroleum diesel. Improving biofuel engine performance requires understanding its fundamental combustion properties and the pathways of combustion. This study's contribution is experimentally validated chemical kinetic combustion mechanisms for biobutanol and biodiesel. Fundamental combustion data and chemical kinetic mechanisms are presented and discussed to improve our understanding of biofuel combustion. The net environmental impact of biobutanol (i.e., n-butanol) has not been studied extensively, so this study first assesses the sustainability of n-butanol derived from corn. The results indicate that technical advances in fuel production are required before commercializing biobutanol. The primary contribution of this research is new experimental data and a novel chemical kinetic mechanism for n-butanol combustion. The results indicate that under the given experimental conditions, n-butanol is consumed primarily via abstraction of hydrogen atoms to produce fuel radical molecules, which subsequently decompose to smaller hydrocarbon and oxygenated species. The hydroxyl moiety in n-butanol results in the direct production of the oxygenated species such as butanal, acetaldehyde, and formaldehyde. The formation of these compounds sequesters carbon from forming soot precursors, but they may introduce other adverse environmental and health effects. Biodiesel is a mixture of long chain fatty acid methyl esters derived from fats and oils. This research study presents high quality experimental data for one large fatty acid methyl ester, methyl decanoate, and models its combustion using an improved skeletal mechanism. The results indicate that methyl decanoate is consumed via abstraction of hydrogen atoms to produce fuel radicals, which ultimately lead to the production of alkenes. The ester moiety in methyl decanoate leads to the formation of low molecular

  3. Modeling the internal combustion engine

    Science.gov (United States)

    Zeleznik, F. J.; Mcbride, B. J.

    1985-01-01

    A flexible and computationally economical model of the internal combustion engine was developed for use on large digital computer systems. It is based on a system of ordinary differential equations for cylinder-averaged properties. The computer program is capable of multicycle calculations, with some parameters varying from cycle to cycle, and has restart capabilities. It can accommodate a broad spectrum of reactants, permits changes in physical properties, and offers a wide selection of alternative modeling functions without any reprogramming. It readily adapts to the amount of information available in a particular case because the model is in fact a hierarchy of five models. The models range from a simple model requiring only thermodynamic properties to a complex model demanding full combustion kinetics, transport properties, and poppet valve flow characteristics. Among its many features the model includes heat transfer, valve timing, supercharging, motoring, finite burning rates, cycle-to-cycle variations in air-fuel ratio, humid air, residual and recirculated exhaust gas, and full combustion kinetics.

  4. Nanoparticle emissions from combustion engines

    CERN Document Server

    Merkisz, Jerzy

    2015-01-01

     This book focuses on particulate matter emissions produced by vehicles with combustion engines. It describes the physicochemical properties of the particulate matter, the mechanisms of its formation and its environmental impacts (including those on human beings). It discusses methods for measuring particulate mass and number, including the state-of-the-art in Portable Emission Measurement System (PEMS) equipment for measuring the exhaust emissions of both light and heavy-duty vehicles and buses under actual operating conditions. The book presents the authors’ latest investigations into the relations between particulate emission (mass and number) and engine operating parameters, as well as their new findings obtained through road tests performed on various types of vehicles, including those using diesel particulate filter regeneration. The book, which addresses the needs of academics and professionals alike, also discusses relevant European regulations on particulate emissions and highlights selected metho...

  5. Hybrid Combustion-Gasification Chemical Looping

    Energy Technology Data Exchange (ETDEWEB)

    Herbert Andrus; Gregory Burns; John Chiu; Gregory Lijedahl; Peter Stromberg; Paul Thibeault

    2009-01-07

    } separation, and also syngas production from coal with the calcium sulfide (CaS)/calcium sulfate (CaSO{sub 4}) loop utilizing the PDU facility. The results of Phase I were reported in Reference 1, 'Hybrid Combustion-Gasification Chemical Looping Coal Power Development Technology Development Phase I Report' The objective for Phase II was to develop the carbonate loop--lime (CaO)/calcium carbonate (CaCO{sub 3}) loop, integrate it with the gasification loop from Phase I, and ultimately demonstrate the feasibility of hydrogen production from the combined loops. The results of this program were reported in Reference 3, 'Hybrid Combustion-Gasification Chemical Looping Coal Power Development Technology Development Phase II Report'. The objective of Phase III is to operate the pilot plant to obtain enough engineering information to design a prototype of the commercial Chemical Looping concept. The activities include modifications to the Phase II Chemical Looping PDU, solids transportation studies, control and instrumentation studies and additional cold flow modeling. The deliverable is a report making recommendations for preliminary design guidelines for the prototype plant, results from the pilot plant testing and an update of the commercial plant economic estimates.

  6. Time Resolved FTIR Analysis of Combustion of Ethanol and Gasoline Combustion in AN Internal Combustion Engine

    Science.gov (United States)

    White, Allen R.; Sakai, Stephen; Devasher, Rebecca B.

    2011-06-01

    In order to pursue In Situ measurements in an internal combustion engine, a MegaTech Mark III transparent spark ignition engine was modified with a sapphire combustion chamber. This modification will allow the transmission of infrared radiation for time-resolved spectroscopic measurements by an infrared spectrometer. By using a Step-scan equipped Fourier transform spectrometer, temporally resolved infrared spectral data were acquired and compared for combustion in the modified Mark III engine. Measurements performed with the FTIR system provide insight into the energy transfer vectors that precede combustion and also provides an in situ measurement of the progress of combustion. Measurements were performed using ethanol and gasoline.

  7. Internal combustion engine and method for control

    Science.gov (United States)

    Brennan, Daniel G

    2013-05-21

    In one exemplary embodiment of the invention an internal combustion engine includes a piston disposed in a cylinder, a valve configured to control flow of air into the cylinder and an actuator coupled to the valve to control a position of the valve. The internal combustion engine also includes a controller coupled to the actuator, wherein the controller is configured to close the valve when an uncontrolled condition for the internal engine is determined.

  8. Combustion calorimetry experimental chemical thermodynamics

    CERN Document Server

    Sunner, Stig

    1979-01-01

    Combustion Calorimetry deals with expertise knowledge concerning the calorimetry of combustion reactions of an element or compound. After defining the use of units and physical constants, the book discusses the basic principles of combustion calorimetry and the various instruments and calorimeters used in the experiments to measure operations concerning temperatures and its time variations. One paper discusses the theory and design criteria of combustion calorimeter calibration. Another paper discusses the results obtained from a combustion calorimeter after it has measured the energy or entha

  9. Establishment of Combustion Model for Isooctane HCCI Marine Diesel Engine and Research on the Combustion Characteristic

    Directory of Open Access Journals (Sweden)

    Li Biao

    2016-01-01

    Full Text Available The homogeneous charge compression ignition (HCCI combustion mode applied in marine diesel engine is expected to be one of alternative technologies to decrease nitrogen oxide (NOX emission and improve energy utilization rate. Applying the chemical-looping combustion (CLC mechanism inside the cylinder, a numerical study on the HCCI combustion process is performed taking a marine diesel engine as application object. The characteristic feature of combustion process is displayed. On this basis, the formation and emission of NOX are analyzed and discussed. The results indicate that the HCCI combustion mode always exhibit two combustion releasing heats: low-temperature reaction and high-temperature reaction. The combustion phase is divided into low-temperature reaction zone, high-temperature reaction zone and negative temperature coefficient (NTC zone. The operating conditions of the high compression ratio, high intake air temperature, low inlet pressure and small excess air coefficient would cause the high in-cylinder pressure which often leads engine detonation. The low compression ratio, low intake air temperature and big excess air coefficient would cause the low combustor temperature which is conducive to reduce NOX emissions. These technological means and operating conditions are expected to meet the NOX emissions limits in MARPOL73/78 Convention-Annex VI Amendment.

  10. Combustion Limits and Efficiency of Turbojet Engines

    Science.gov (United States)

    Barnett, H. C.; Jonash, E. R.

    1956-01-01

    Combustion must be maintained in the turbojet-engine combustor over a wide range of operating conditions resulting from variations in required engine thrust, flight altitude, and flight speed. Furthermore, combustion must be efficient in order to provide the maximum aircraft range. Thus, two major performance criteria of the turbojet-engine combustor are (1) operatable range, or combustion limits, and (2) combustion efficiency. Several fundamental requirements for efficient, high-speed combustion are evident from the discussions presented in chapters III to V. The fuel-air ratio and pressure in the burning zone must lie within specific limits of flammability (fig. 111-16(b)) in order to have the mixture ignite and burn satisfactorily. Increases in mixture temperature will favor the flammability characteristics (ch. III). A second requirement in maintaining a stable flame -is that low local flow velocities exist in the combustion zone (ch. VI). Finally, even with these requirements satisfied, a flame needs a certain minimum space in which to release a desired amount of heat, the necessary space increasing with a decrease in pressure (ref. 1). It is apparent, then, that combustor design and operation must provide for (1) proper control of vapor fuel-air ratios in the combustion zone at or near stoichiometric, (2) mixture pressures above the minimum flammability pressures, (3) low flow velocities in the combustion zone, and (4) adequate space for the flame.

  11. Two phase exhaust for internal combustion engine

    Science.gov (United States)

    Vuk, Carl T.

    2011-11-29

    An internal combustion engine having a reciprocating multi cylinder internal combustion engine with multiple valves. At least a pair of exhaust valves are provided and each supply a separate power extraction device. The first exhaust valves connect to a power turbine used to provide additional power to the engine either mechanically or electrically. The flow path from these exhaust valves is smaller in area and volume than a second flow path which is used to deliver products of combustion to a turbocharger turbine. The timing of the exhaust valve events is controlled to produce a higher grade of energy to the power turbine and enhance the ability to extract power from the combustion process.

  12. Application of Detailed Chemical Kinetics to Combustion Instability Modeling

    Science.gov (United States)

    2016-01-04

    under two different conditions corresponding to marginally stable and unstable operation in order to evaluate the performance of the chemical kinetics...instability is a complex interaction between acoustics and the heat release due to combustion.In rocket engines, which are acoustically compact, there is...and amplitudes remains a challenge. The present article is an attempt towards addressing such discrepancies by enhancing the chemical kinetics model

  13. Reduced chemical reaction mechanisms: experimental and HCCI modelling investigations of autoignition processes of iso-octane in internal combustion engines

    OpenAIRE

    Machrafi, Hatim; Lombaert, K.; Cavadias, S; Guibert, P.; Amouroux, J

    2005-01-01

    A semi-reduced (70 species, 210 reactions) and a skeletal (27 species, 29 reactions) chemical reaction mechanism for iso-octane are constructed from a semi-detailed iso-octane mechanism (84 species, 412 reactions) of the Chalmers University of Technology in Sweden. The construction of the reduced mechanisms is performed by using reduction methods such as the quasi-steady-state assumption and the partial equilibrium assumption. The obtained reduced iso-octane mechanisms show, at the mentioned ...

  14. Analysis of nonequilibrium chemical processes in the plume of subsonic and supersonic aircraft with hydrogen and hydrocarbon combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Starik, A.M.; Lebedev, A.B.; Titova, N.S. [Central Inst. of Aviation Motors, Moscow (Russian Federation)

    1997-12-31

    On the basic of quasi one dimensional mixing model the numerical analysis of nonequilibrium chemical processes in the plume of subsonic and hypersonic aircraft is presented. It was found that species HNO, HNO{sub 3}, HNO{sub 4}, N{sub 2}O{sub 5}, ClO{sub 2}, CH{sub 3}NO{sub 2} could be formed as a result of nonequilibrium processes in the plume and their concentrations can essentially exceed both background values in free stream of atmosphere and their values at the nozzle exit plane. (author) 10 refs.

  15. External combustion wankel engine for solar applications

    Energy Technology Data Exchange (ETDEWEB)

    Kovarsky, N.; Kaftori, D.; Gamzon, E.; Dgani, E. [Silver Arrow (Israel)

    1999-03-01

    An External Combustion Wankel Engine (ECWE), intended for use in a dish-engine solar power plant is discussed. The engine operates in a Brayton cycle using a gaseous working fluid, which is heated outside of the engine by concentrated solar radiation or fossil fuel. A computer simulation code that models the ECWE's operation and performance has been developed The program takes into account all of the engine's characteristics, subsystems and operating conditions. In the present work, the advantages and features of ECWE are considered in detail, together with simulation results of its performance. (authors)

  16. Using Alcohols as an Alternative Fuel in Internal Combustion Engines

    Directory of Open Access Journals (Sweden)

    Salih ÖZER

    2014-04-01

    Full Text Available This study summarizes the studies on alcohol use in internal combustion engines nature. Nowadays, alcohol is used in internal combustion engines sometimes in order to reduce emissions and sometimes as an alternative fuel. Even vehicle manufacturers are producing and launching vehicles that are running directly with alcohol. Many types of pure alcohol that can be used on vehicles are available on the world. Using all of these types of alcohol led to the formation of engine emissions and power curves. The studies reveal that these changes are because of the physical and chemical characteristics of alcohols. Thıs study tries to explain what kind of conclusions the physical and chemical properties cause

  17. Effect of Gas Mixture Composition on the Parameters of an Internal Combustion Engine

    Directory of Open Access Journals (Sweden)

    Andrej Chríbik

    2012-01-01

    Full Text Available This paper deals with the use of the internal combustion piston engine, which is a drive unit for micro-cogeneration units. The introduction is a brief statement of the nature of gas mixture compositions that are useful for the purposes of combustion engines, together with the basic physical and chemical properties relevant to the burning of this gas mixture. Specifically, we will discuss low-energy gases (syngases and mixtures of natural gas with hydrogen. The second section describes the conversion of the Lombardini LGW 702 combustion engine that is necessary for these types of combustion gases. Before the experimental measurements, a simulation in the Lotus Engine simulation program was carried out to make a preliminary assessment of the impact on the performance of an internal combustion engine. The last section of the paper presents the experimental results of partial measurements of the performance and emission parameters of an internal combustion engine powered by alternative fuels.

  18. Engine combustion control via fuel reactivity stratification

    Energy Technology Data Exchange (ETDEWEB)

    Reitz, Rolf Deneys; Hanson, Reed M.; Splitter, Derek A.; Kokjohn, Sage L.

    2015-07-14

    A compression ignition engine uses two or more fuel charges having two or more reactivities to control the timing and duration of combustion. In a preferred implementation, a lower-reactivity fuel charge is injected or otherwise introduced into the combustion chamber, preferably sufficiently early that it becomes at least substantially homogeneously dispersed within the chamber before a subsequent injection is made. One or more subsequent injections of higher-reactivity fuel charges are then made, and these preferably distribute the higher-reactivity matter within the lower-reactivity chamber space such that combustion begins in the higher-reactivity regions, and with the lower-reactivity regions following thereafter. By appropriately choosing the reactivities of the charges, their relative amounts, and their timing, combustion can be tailored to achieve optimal power output (and thus fuel efficiency), at controlled temperatures (and thus controlled NOx), and with controlled equivalence ratios (and thus controlled soot).

  19. Engine combustion control via fuel reactivity stratification

    Energy Technology Data Exchange (ETDEWEB)

    Reitz, Rolf Deneys; Hanson, Reed M.; Splitter, Derek A.; Kokjohn, Sage L.

    2016-06-28

    A compression ignition engine uses two or more fuel charges having two or more reactivities to control the timing and duration of combustion. In a preferred implementation, a lower-reactivity fuel charge is injected or otherwise introduced into the combustion chamber, preferably sufficiently early that it becomes at least substantially homogeneously dispersed within the chamber before a subsequent injection is made. One or more subsequent injections of higher-reactivity fuel charges are then made, and these preferably distribute the higher-reactivity matter within the lower-reactivity chamber space such that combustion begins in the higher-reactivity regions, and with the lower-reactivity regions following thereafter. By appropriately choosing the reactivities of the charges, their relative amounts, and their timing, combustion can be tailored to achieve optimal power output (and thus fuel efficiency), at controlled temperatures (and thus controlled NOx), and with controlled equivalence ratios (and thus controlled soot).

  20. Engine combustion control via fuel reactivity stratification

    Science.gov (United States)

    Reitz, Rolf Deneys; Hanson, Reed M; Splitter, Derek A; Kokjohn, Sage L

    2013-12-31

    A compression ignition engine uses two or more fuel charges having two or more reactivities to control the timing and duration of combustion. In a preferred implementation, a lower-reactivity fuel charge is injected or otherwise introduced into the combustion chamber, preferably sufficiently early that it becomes at least substantially homogeneously dispersed within the chamber before a subsequent injection is made. One or more subsequent injections of higher-reactivity fuel charges are then made, and these preferably distribute the higher-reactivity matter within the lower-reactivity chamber space such that combustion begins in the higher-reactivity regions, and with the lower-reactivity regions following thereafter. By appropriately choose the reactivities of the charges, their relative amounts, and their timing, combustion can be tailored to achieve optimal power output (and thus fuel efficiency), at controlled temperatures (and thus controlled NOx), and with controlled equivalence ratios (and thus controlled soot).

  1. Wear aspects of internal combustion engine valves

    Science.gov (United States)

    Panţuru, M.; Chicet, D.; Paulin, C.; Alexandru, A.; Munteanu, C.

    2016-08-01

    Because the surface engineering is becoming an increasingly viable alternative to the constructive changes made to improve the efficiency of internal combustion engines, have been proposed and tested various types of coatings of some organs of internal combustion engines. One vital organ is the engine valves, which is subjected during operation to combined thermal, mechanical, corrosion and wear solicitations, which are leading to severe corrosion and complete breakdown. In this paper were analyzed aspects of valves wear and the active surfaces were coated using the atmospheric plasma spraying method (APS) with two commercial powders: Ni-Al and YSZ. Microstructural analyzes were made on these layers and also observations regarding the possibility of using them as thermal barrier and anti-oxidant coatings.

  2. Nanotechnology for chemical engineers

    CERN Document Server

    Salaheldeen Elnashaie, Said; Hashemipour Rafsanjani, Hassan

    2015-01-01

    The book describes the basic principles of transforming nano-technology into nano-engineering with a particular focus on chemical engineering fundamentals. This book provides vital information about differences between descriptive technology and quantitative engineering for students as well as working professionals in various fields of nanotechnology. Besides chemical engineering principles, the fundamentals of nanotechnology are also covered along with detailed explanation of several specific nanoscale processes from chemical engineering point of view. This information is presented in form of practical examples and case studies that help the engineers and researchers to integrate the processes which can meet the commercial production. It is worth mentioning here that, the main challenge in nanostructure and nanodevices production is nowadays related to the economic point of view. The uniqueness of this book is a balance between important insights into the synthetic methods of nano-structures and nanomaterial...

  3. ABB Combustion Engineering`s nuclear experience and technologies

    Energy Technology Data Exchange (ETDEWEB)

    Matzie, R.A.

    1994-12-31

    ABB Combustion Engineering`s nuclear experience and technologies are outlined. The following topics are discussed: evolutionary approach using proven technology, substantial improvement to plant safety, utility perspective up front in developing design, integrated design, competitive plant cost, operability and maintainability, standardization, and completion of US NRC technical review.

  4. COMBUSTION SIMULATION IN A SPARK IGNITION ENGINE CYLINDER: EFFECTS OF AIR-FUEL RATIO ON THE COMBUSTION DURATION

    OpenAIRE

    2010-01-01

    Combustion is an important subject of internal combustion engine studies. To reduce the air pollution from internal combustion engines and to increase the engine performance, it is required to increase combustion efficiency. In this study, effects of air/fuel ratio were investigated numerically. An axisymmetrical internal combustion engine was modeled in order to simulate in-cylinder engine flow and combustion. Two dimensional transient continuity, momentum, turbulence, energy, and combustion...

  5. Supersonic combustion engine testbed, heat lightning

    Science.gov (United States)

    Hoying, D.; Kelble, C.; Langenbahn, A.; Stahl, M.; Tincher, M.; Walsh, M.; Wisler, S.

    1990-01-01

    The design of a supersonic combustion engine testbed (SCET) aircraft is presented. The hypersonic waverider will utilize both supersonic combustion ramjet (SCRAMjet) and turbofan-ramjet engines. The waverider concept, system integration, electrical power, weight analysis, cockpit, landing skids, and configuration modeling are addressed in the configuration considerations. The subsonic, supersonic and hypersonic aerodynamics are presented along with the aerodynamic stability and landing analysis of the aircraft. The propulsion design considerations include: engine selection, turbofan ramjet inlets, SCRAMjet inlets and the SCRAMjet diffuser. The cooling requirements and system are covered along with the topics of materials and the hydrogen fuel tanks and insulation system. A cost analysis is presented and the appendices include: information about the subsonic wind tunnel test, shock expansion calculations, and an aerodynamic heat flux program.

  6. Co-Optimization of Internal Combustion Engines and Biofuels

    Energy Technology Data Exchange (ETDEWEB)

    McCormick, Robert L.

    2016-03-08

    The development of advanced engines has significant potential advantages in reduced aftertreatment costs for air pollutant emission control, and just as importantly for efficiency improvements and associated greenhouse gas emission reductions. There are significant opportunities to leverage fuel properties to create more optimal engine designs for both advanced spark-ignition and compression-ignition combustion strategies. The fact that biofuel blendstocks offer a potentially low-carbon approach to fuel production, leads to the idea of optimizing the entire fuel production-utilization value chain as a system from the standpoint of life cycle greenhouse gas emissions. This is a difficult challenge that has yet to be realized. This presentation will discuss the relationship between chemical structure and critical fuel properties for more efficient combustion, survey the properties of a range of biofuels that may be produced in the future, and describe the ongoing challenges of fuel-engine co-optimization.

  7. Analysis of rocket engine injection combustion processes

    Science.gov (United States)

    Salmon, J. W.

    1976-01-01

    A critique is given of the JANNAF sub-critical propellant injection/combustion process analysis computer models and application of the models to correlation of well documented hot fire engine data bases. These programs are the distributed energy release (DER) model for conventional liquid propellants injectors and the coaxial injection combustion model (CICM) for gaseous annulus/liquid core coaxial injectors. The critique identifies model inconsistencies while the computer analyses provide quantitative data on predictive accuracy. The program is comprised of three tasks: (1) computer program review and operations; (2) analysis and data correlations; and (3) documentation.

  8. Chemical Engineering at NASA

    Science.gov (United States)

    Collins, Jacob

    2008-01-01

    This viewgraph presentation is a review of the career paths for chemicals engineer at NASA (specifically NASA Johnson Space Center.) The author uses his personal experience and history as an example of the possible career options.

  9. Miniature free-piston homogeneous charge compression ignition engine-compressor concept - Part II: modeling HCCI combustion in small scales with detailed homogeneous gas phase chemical kinetics

    Energy Technology Data Exchange (ETDEWEB)

    Aichlmayr, H.T.; Kittelson, D.B.; Zachariah, M.R. [The University of Minnesota, Minneapolis (United States). Departments of Mechanical Engineering and Chemistry

    2002-10-01

    Operational maps for crankshaft-equipped miniature homogeneous charge compression ignition engines are established using performance estimation, detailed chemical kinetics, and diffusion models for heat transfer and radical loss. In this study, radical loss was found to be insignificant. In contrast, heat transfer was found to be increasingly significant for 10, 1, and 0.1 W engines, respectively. Also, temperature-pressure trajectories and ignition delay time maps are used to explore relationships between engine operational parameters and HCCI. Lastly, effects of engine operating conditions and design on the indicated fuel conversion efficiency are investigated. (author)

  10. Chemical Kinetic Modeling of 2-Methylhexane Combustion

    KAUST Repository

    Mohamed, Samah Y.

    2015-03-30

    Accurate chemical kinetic combustion models of lightly branched alkanes (e.g., 2-methylalkanes) are important for investigating the combustion behavior of diesel, gasoline, and aviation fuels. Improving the fidelity of existing kinetic models is a necessity, as new experiments and advanced theories show inaccuracy in certain portions of the models. This study focuses on updating thermodynamic data and kinetic model for a gasoline surrogate fuel, 2-methylhexane, with recently published group values and rate rules. These update provides a better agreement with rapid compression machine measurements of ignition delay time, while also strengthening the fundamental basis of the model.

  11. Combustion and Engine-Core Noise

    Science.gov (United States)

    Ihme, Matthias

    2017-01-01

    The implementation of advanced low-emission aircraft engine technologies and the reduction of noise from airframe, fan, and jet exhaust have made noise contributions from an engine core increasingly important. Therefore, meeting future ambitious noise-reduction goals requires the consideration of engine-core noise. This article reviews progress on the fundamental understanding, experimental analysis, and modeling of engine-core noise; addresses limitations of current techniques; and identifies opportunities for future research. After identifying core-noise contributions from the combustor, turbomachinery, nozzles, and jet exhaust, they are examined in detail. Contributions from direct combustion noise, originating from unsteady combustion, and indirect combustion noise, resulting from the interaction of flow-field perturbations with mean-flow variations in turbine stages and nozzles, are analyzed. A new indirect noise-source contribution arising from mixture inhomogeneities is identified by extending the theory. Although typically omitted in core-noise analysis, the impact of mean-flow variations and nozzle-upstream perturbations on the jet-noise modulation is examined, providing potential avenues for future core-noise mitigation.

  12. High Frequency Combustion Instabilities of LOx/CH4 Spray Flames in Rocket Engine Combustion Chambers

    NARCIS (Netherlands)

    Sliphorst, M.

    2011-01-01

    Ever since the early stages of space transportation in the 1940’s, and the related liquid propellant rocket engine development, combustion instability has been a major issue. High frequency combustion instability (HFCI) is the interaction between combustion and the acoustic field in the combustion c

  13. Chemical Looping Combustion of Rice Husk

    Directory of Open Access Journals (Sweden)

    Rashmeet Singh Monga

    2015-05-01

    Full Text Available A thermodynamic investigation of direct chemical looping combustion (CLC of rice husk is presented in this paper. Both steam and CO2 are used for gasification within the temperature range of 500–1200˚C and different amounts of oxygen carriers. Chemical equilibrium model was considered for the CLC fuel reactor. The trends in product compositions of the fuel reactor, were determined. Rice husk gasification using 3 moles H2O and 0 moles CO2 per mole carbon (in rice husk at 1 bar pressure and 900˚C was found to be the best operating point for hundred percent carbon conversion in the fuel reactor. Such detailed thermodynamic studies can be useful to design chemical looping combustion processes using different fuels.

  14. Comparison of combustion efficiencies for ramjet engines

    Science.gov (United States)

    Bergmann, J. W.

    1984-01-01

    Four different combustion efficiencies commonly used for assessing ramjet engines are compared. The mixture ratios cover a range from stoichiometric to an equivalence ratio of 0.2, and the polyethylene/air propellant system is used. The ratio of effective to ideal temperature rise is taken as reference efficiency. As might be expected, major differences can be observed near stoichiometric and down to equilvalence ratios of 0.5. These are quantitatively demonstrated.

  15. Wall Effects on Combustion in an Engine.

    Science.gov (United States)

    1984-05-14

    AD-A41 418 WAL EFFECT ONCOMBUSTION INAN ENGNEU) TRW SPACE AND TECHNOLOGY GROUP REDONDO BEACH CA ENGINEERIHG S c SCENCES LAB E FENDEL 14 MUY 84 NRW-S...NO. NO. NO. 11. TITLE (Include Security Claaification, Wall Effects on Combustion in an Engine (U)7 12. PERSONAL AUTHOR(S) Fendell , Francis Edward 13a...heat transfer as a determent of end-gas knock in a homo- geneous-charge engine was undertaken (Carrier, Fendell , Fink, and Feldman 1984). The last

  16. Tailoring next-generation biofuels and their combustion in next-generation engines.

    Energy Technology Data Exchange (ETDEWEB)

    Gladden, John Michael; Wu, Weihua; Taatjes, Craig A.; Scheer, Adam Michael; Turner, Kevin M.; Yu, Eizadora T.; O' Bryan, Greg; Powell, Amy Jo; Gao, Connie W.

    2013-11-01

    Increasing energy costs, the dependence on foreign oil supplies, and environmental concerns have emphasized the need to produce sustainable renewable fuels and chemicals. The strategy for producing next-generation biofuels must include efficient processes for biomass conversion to liquid fuels and the fuels must be compatible with current and future engines. Unfortunately, biofuel development generally takes place without any consideration of combustion characteristics, and combustion scientists typically measure biofuels properties without any feedback to the production design. We seek to optimize the fuel/engine system by bringing combustion performance, specifically for advanced next-generation engines, into the development of novel biosynthetic fuel pathways. Here we report an innovative coupling of combustion chemistry, from fundamentals to engine measurements, to the optimization of fuel production using metabolic engineering. We have established the necessary connections among the fundamental chemistry, engine science, and synthetic biology for fuel production, building a powerful framework for co-development of engines and biofuels.

  17. High Frequency Combustion Instabilities of LOx/CH4 Spray Flames in Rocket Engine Combustion Chambers

    OpenAIRE

    Sliphorst, M.

    2011-01-01

    Ever since the early stages of space transportation in the 1940’s, and the related liquid propellant rocket engine development, combustion instability has been a major issue. High frequency combustion instability (HFCI) is the interaction between combustion and the acoustic field in the combustion chamber. It destroys the thermal boundary layer wall increasing heat transfer and could lead to compromised performance, and ultimately to destruction of the engine and mission loss. The main object...

  18. Electrochemical energy engineering: a new frontier of chemical engineering innovation.

    Science.gov (United States)

    Gu, Shuang; Xu, Bingjun; Yan, Yushan

    2014-01-01

    One of the grand challenges facing humanity today is a safe, clean, and sustainable energy system where combustion no longer dominates. This review proposes that electrochemical energy conversion could set the foundation for such an energy system. It further suggests that a simple switch from an acid to a base membrane coupled with innovative cell designs may lead to a new era of affordable electrochemical devices, including fuel cells, electrolyzers, solar hydrogen generators, and redox flow batteries, for which recent progress is discussed using the authors' work as examples. It also notes that electrochemical energy engineering will likely become a vibrant subdiscipline of chemical engineering and a fertile ground for chemical engineering innovation. To realize this vision, it is necessary to incorporate fundamental electrochemistry and electrochemical engineering principles into the chemical engineering curriculum.

  19. High efficiency stoichiometric internal combustion engine system

    Science.gov (United States)

    Winsor, Richard Edward; Chase, Scott Allen

    2009-06-02

    A power system including a stoichiometric compression ignition engine in which a roots blower is positioned in the air intake for the engine to control air flow. Air flow is decreased during part power conditions to maintain the air-fuel ratio in the combustion chamber of the engine at stoichiometric, thus enabling the use of inexpensive three-way catalyst to reduce oxides of nitrogen. The roots blower is connected to a motor generator so that when air flow is reduced, electrical energy is stored which is made available either to the roots blower to temporarily increase air flow or to the system electrical load and thus recapture energy that would otherwise be lost in reducing air flow.

  20. Towards the regulation of aerosol emissions by their potential health impact: Assessing adverse effects of aerosols from wood combustion and ship diesel engine emissions by combining comprehensive data on the chemical composition and their toxicological effects on human lung cells

    Science.gov (United States)

    Zimmermann, R.; Streibel, T.; Dittmar, G.; Kanashova, T.; Buters, J.; Öder, S.; Paur, H. R.; Dilger, M.; Weiss, C.; Harndorf, H.; Stengel, B.; Hirvonen, M. R.; Jokiniemi, J.; Hiller, K.; Sapcariu, S.; Sippula, O.; Orasche, J.; Müller, L.; Rheda, A.; Passig, J.; Radischat, C.; Czech, H.; Tiita, P.; Jalava, P.; Kasurinen, S.; Schwemer, T.; Yli-Prilä, P.; Tissari, J.; Lamberg, H.; Schnelle-Kreis, J.

    2014-12-01

    Ship engine emissions are important regarding lung and cardiovascular diseases in coastal regions worldwide. Bio mass burning is made responsible for adverse health effects in many cities and rural regions. The Virtual Helmholtz Institute-HICE (www.hice-vi.eu) addresses chemical & physical properties and health effects of anthropogenic combustion emissions. Typical lung cell responses to combustion aerosols include inflammation and apoptosis, but a molecular link with the specific chemical composition in particular of ship emissions has not been established. Through an air-liquid interface exposure system (ALI), we exposed human lung cells at-site to exhaust fumes from a ship engine running on common heavy fuel oil (HFO) and cleaner-burning diesel fuel (DF) as well as to emissions of wood combustion compliances. A special field deployable ALI-exposition system and a mobile S2-biological laboratory were developed for this study. Human alveolar basal epithelial cells (A549 etc.) are ALI-exposed to fresh, diluted (1:40-1:100) combustion aerosols and subsequently were toxicologically and molecular-biologically characterized. Advanced chemical analyses of the exhaust aerosols were combined with transcriptional, proteomic and metabolomic profiling to characterise the cellular responses. The HFO ship emissions contained high concentrations of toxic compounds (transition metals, organic toxicants) and particle masses. The cellular responses included inflammation and oxidative stress. Surprisingly, the DF ship emissions, which predominantly contain rather "pure" carbonaceous soot and much less known toxicants, induced significantly broader biological effects, affecting essential cellular pathways (e.g., mitochondrial function and intracellular transport). Therefore the use of distillate fuels for shipping (this is the current emission reduction strategy of the IMO) appears insufficient for diminishing health effects. The study suggests rather reducing the particle emissions

  1. Studies on pressure-gain combustion engines

    Science.gov (United States)

    Matsutomi, Yu

    Various aspects of the pressure-gain combustion engine are investigated analytically and experimentally in the current study. A lumped parameter model is developed to characterize the operation of a valveless pulse detonation engine. The model identified the function of flame quenching process through gas dynamic process. By adjusting fuel manifold pressure and geometries, the duration of the air buffer can be effectively varied. The parametric study with the lumped parameter model has shown that engine frequency of up to approximately 15 Hz is attainable. However, requirements for upstream air pressure increases significantly with higher engine frequency. The higher pressure requirement indicates pressure loss in the system and lower overall engine performance. The loss of performance due to the pressure loss is a critical issue for the integrated pressure-gain combustors. Two types of transitional methods are examined using entropy-based models. An accumulator based transition has obvious loss due to sudden area expansion, but it can be minimized by utilizing the gas dynamics in the combustion tube. An ejector type transition has potential to achieve performance beyond the limit specified by a single flow path Humphrey cycle. The performance of an ejector was discussed in terms of apparent entropy and mixed flow entropy. Through an ideal ejector, the apparent part of entropy increases due to the reduction in flow unsteadiness, but entropy of the mixed flow remains constant. The method is applied to a CFD simulation with a simple manifold for qualitative evaluation. The operation of the wave rotor constant volume combustion rig is experimentally examined. The rig has shown versatility of operation for wide range of conditions. Large pressure rise in the rotor channel and in a section of the exhaust duct are observed even with relatively large leakage gaps on the rotor. The simplified analysis indicated that inconsistent combustion is likely due to insufficient

  2. Applied chemical engineering thermodynamics

    CERN Document Server

    Tassios, Dimitrios P

    1993-01-01

    Applied Chemical Engineering Thermodynamics provides the undergraduate and graduate student of chemical engineering with the basic knowledge, the methodology and the references he needs to apply it in industrial practice. Thus, in addition to the classical topics of the laws of thermodynamics,pure component and mixture thermodynamic properties as well as phase and chemical equilibria the reader will find: - history of thermodynamics - energy conservation - internmolecular forces and molecular thermodynamics - cubic equations of state - statistical mechanics. A great number of calculated problems with solutions and an appendix with numerous tables of numbers of practical importance are extremely helpful for applied calculations. The computer programs on the included disk help the student to become familiar with the typical methods used in industry for volumetric and vapor-liquid equilibria calculations.

  3. ANALYSIS OF INTERNAL COMBUSTION ENGINE WITH A NEW CONCEPT OF POROUS MEDIUM COMBUSTION FOR THE FUTURE CLEAN ENGINE

    Directory of Open Access Journals (Sweden)

    Ashok A Dhale

    2010-01-01

    Full Text Available At present, the emissions of internal combustion engine can only be improved by catalytic treatments of the exhaust gases. Such treatments, however, result in high costs and relatively low conversion efficiency. This suggests that a new combustion technique should be developed to yield improved primary combustion processes inside the engine with drastically reduced exhaust gas emissions. To fulfill all requirements, Dr. Franz Drust has proposed a new combustion concept to perform homogenous combustion in internal combustion engines. This concept used the porous medium combustion technique and is called "PM-engine". It is shown that the PM combustion technique can be applied to internal combustion engines. Theoretical considerations are presented for internal combustion engines, indicating that an overall improvement in thermal efficiency can be achieved for the PM-engine. This is explained and general performance of the new PM-engines is demonstrated for a single cylinder, water cooled, direct injection diesel engine. Verification of experiments at primary stage is described that were carried out as a part of the present study.

  4. Combustion Temperature Effect of Diesel Engine Convert to Compressed Natural Gas Engine

    OpenAIRE

    Semin; Abdul R. Ismail; Rosli A. Bakar

    2009-01-01

    Effect of combustion temperature in the engine cylinder of diesel engine convert to Compressed Natural Gas (CNG) engine was presents in this study. The objective of this study was to investigate the engine cylinder combustion temperature effect of diesel engine convert to CNG engine on variation engine speed. Problem statement: The hypothesis was that the lower performance of CNG engine was caused by the effect of lower in engine cylinder temperature. Are the CNG engine is lower cylinder temp...

  5. Statistics of indicated pressure in combustion engine.

    Science.gov (United States)

    Sitnik, L. J.; Andrych-Zalewska, M.

    2016-09-01

    The paper presents the classic form of pressure waveforms in burn chamber of diesel engine but based on strict analytical basis for amending the displacement volume. The pressure measurement results are obtained in the engine running on an engine dynamometer stand. The study was conducted by a 13-phase ESC test (European Stationary Cycle). In each test phase are archived 90 waveforms of pressure. As a result of extensive statistical analysis was found that while the engine is idling distribution of 90 value of pressure at any value of the angle of rotation of the crankshaft can be described uniform distribution. In the each point of characteristic of the engine corresponding to the individual phases of the ESC test, 90 of the pressure for any value of the angle of rotation of the crankshaft can be described as normal distribution. These relationships are verified using tests: Shapiro-Wilk, Jarque-Bera, Lilliefors, Anderson-Darling. In the following part, with each value of the crank angle, are obtain values of descriptive statistics for the pressure data. In its essence, are obtained a new way to approach the issue of pressure waveform analysis in the burn chamber of engine. The new method can be used to further analysis, especially the combustion process in the engine. It was found, e.g. a very large variances of pressure near the transition from compression to expansion stroke. This lack of stationarity of the process can be important both because of the emissions of exhaust gases and fuel consumption of the engine.

  6. Internal combustion engine with compound air compression

    Energy Technology Data Exchange (ETDEWEB)

    Paul, M.A.; Paul, A.

    1991-10-15

    This patent describes an internal combustion engine in combination with a compound air compression system. It comprises: a reciprocator with at least one cylinder, at least one piston reciprocal in the cylinder and a combustion chamber formed in substantial part by portions of the piston and cylinder, the reciprocator having a drive shaft; a rotary compressor having a drive shaft mechanically coupled to the drive shaft of the reciprocator, the rotary compressor having a Wankel-type, three-lobe, epitrochiodal configuration sides having a conduit conjected to the reciprocator for supplying compressed air to the reciprocator; a turbocharged with a gas turbine and a turbocompressor, the turbocompressor having an air conduit connected to the expander side of the rotary compressor; and a bypass conduit with a valve means connecting the turbocharger to the reciprocator for supplying compressed air directly to the reciprocator wherein the drive shaft of the reciprocator and the drive shaft of the compressor have connecting means for transmitting mechanical energy to the reciprocator at mid to high operating speeds of the engine when the turbocharge supplies compressed air to the rotary compressor and, at least in part, drives the rotary compressor.

  7. Internal combustion engine using premixed combustion of stratified charges

    Science.gov (United States)

    Marriott, Craig D.; Reitz, Rolf D. (Madison, WI

    2003-12-30

    During a combustion cycle, a first stoichiometrically lean fuel charge is injected well prior to top dead center, preferably during the intake stroke. This first fuel charge is substantially mixed with the combustion chamber air during subsequent motion of the piston towards top dead center. A subsequent fuel charge is then injected prior to top dead center to create a stratified, locally richer mixture (but still leaner than stoichiometric) within the combustion chamber. The locally rich region within the combustion chamber has sufficient fuel density to autoignite, and its self-ignition serves to activate ignition for the lean mixture existing within the remainder of the combustion chamber. Because the mixture within the combustion chamber is overall premixed and relatively lean, NO.sub.x and soot production are significantly diminished.

  8. Turbulence-combustion interaction in direct injection diesel engine

    Directory of Open Access Journals (Sweden)

    Bencherif Mohamed

    2014-01-01

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

  9. Combustion

    CERN Document Server

    Glassman, Irvin

    1987-01-01

    Combustion, Second Edition focuses on the underlying principles of combustion and covers topics ranging from chemical thermodynamics and flame temperatures to chemical kinetics, detonation, ignition, and oxidation characteristics of fuels. Diffusion flames, flame phenomena in premixed combustible gases, and combustion of nonvolatile fuels are also discussed. This book consists of nine chapters and begins by introducing the reader to heats of reaction and formation, free energy and the equilibrium constants, and flame temperature calculations. The next chapter explores the rates of reactio

  10. Compounded turbocharged rotary internal combustion engine fueled with natural gas

    Energy Technology Data Exchange (ETDEWEB)

    Jenkins, P.E.

    1992-10-15

    This patent describes a compounded engine. It comprises: a first Wankel engine having a housing with a trochoidal inner surface containing a generally triangular shaped rotor, the engine containing a fuel supply system suitable for operating the engine with natural gas as a fuel; a turbocharge compressing air for combustion by the engine, the turbocharger being driven by the exhaust gases which exit from the engine; a combustion chamber in fluid communication with the exhaust from the engine after that exhaust has passed through the turbocharger, the chamber having an ignition device suitable for igniting hydrocarbons in the engine exhaust, whereby the engine timing, and the air and fuel mixture of the engine are controlled so that when the engine exhaust reaches the combustion chamber the exhaust contains a sufficient amount of oxygen and hydrocarbons to enable ignition and combustion of the engine exhaust in the combustion chamber without the addition of fuel or air, and whereby the engine operating conditions are controlled to vary the performance of the secondary combustor; and a controllable ignition device to ignite the exhaust gases in the combustion chamber at predetermined times.

  11. Chemical Engineering in Space

    Science.gov (United States)

    Lobmeyer, Dennis A.; Meneghelli, Barry; Steinrock, Todd (Technical Monitor)

    2001-01-01

    The aerospace industry has long been perceived as the domain of both physicists and mechanical engineers. This perception has endured even though the primary method of providing the thrust necessary to launch a rocket into space is chemical in nature. The chemical engineering and chemistry personnel behind the systems that provide access to space have labored in the shadows of the physicists and mechanical engineers. As exploration into the cosmos moves farther away from Earth, there is a very distinct need for new chemical processes to help provide the means for advanced space exploration. The state of the art in launch systems uses chemical propulsion systems, primarily liquid hydrogen and liquid oxygen, to provide the energy necessary to achieve orbit. As we move away from Earth, there are additional options for propulsion. Unfortunately, few of these options can compare to the speed or ease of use provided by the chemical propulsion agents. It is with great care and significant cost that gaseous compounds such as hydrogen and oxygen are liquefied and become dense enough to use for rocket fuel. These low-temperature liquids fall within a specialty area known as cryogenics. Cryogenics, the science and art of producing cold operating conditions for use on Earth, in orbit, or on some other nonterrestrial body, has become increasingly important to our ability to travel within our solar system. The production of cryogenic fuels and the long-term storage of these fluids are necessary for travel. As our explorations move farther away from Earth, we need to address how to produce the necessary fuels to make a round-trip. The cost and the size of these expeditions are extreme at best. If we take everything necessary for our survival for the round-trip, we invalidate any chance of travel in the near future. As with the early explorers on Earth, we need to harvest much of our energy and our life support from the celestial bodies. The in situ production of these energy

  12. Comprehensive study of biodiesel fuel for HSDI engines in conventional and low temperature combustion conditions

    Energy Technology Data Exchange (ETDEWEB)

    Tormos, Bernardo; Novella, Ricardo; Garcia, Antonio; Gargar, Kevin [CMT-Motores Termicos, Universidad Politecnica de Valencia, Valencia, ES, Campus de Vera, s/n, Edificio 6D. Camino de Vera s/n, 46022 Valencia (Spain)

    2010-02-15

    In this research, an experimental investigation has been performed to give insight into the potential of biodiesel as an alternative fuel for High Speed Direct Injection (HSDI) diesel engines. The scope of this work has been broadened by comparing the combustion characteristics of diesel and biodiesel fuels in a wide range of engine loads and EGR conditions, including the high EGR rates expected for future diesel engines operating in the low temperature combustion (LTC) regime. The experimental work has been carried out in a single-cylinder engine running alternatively with diesel and biodiesel fuels. Conventional diesel fuel and neat biodiesel have been compared in terms of their combustion performance through a new methodology designed for isolating the actual effects of each fuel on diesel combustion, aside from their intrinsic differences in chemical composition. The analysis of the results has been sequentially divided into two progressive and complementary steps. Initially, the overall combustion performance of each fuel has been critically evaluated based on a set of parameters used as tracers of the combustion quality, such as the combustion duration or the indicated efficiency. With the knowledge obtained from this previous overview, the analysis focuses on the detailed influence of biodiesel on the different diesel combustion stages known ignition delay, premixed combustion and mixing controlled combustion, considering also the impact on CO and UHC (unburn-hydrocarbons) pollutant emissions. The results of this research explain why the biodiesel fuel accelerates the diesel combustion process in all engine loads and EGR rates, even in those corresponding with LTC conditions, increasing its possibilities as alternative fuel for future DI diesel engines. (author)

  13. FY2014 Advanced Combustion Engine Annual Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    None

    2015-03-01

    The Advanced Combustion Engine research and development (R&D) subprogram within the DOE Vehicle Technologies Office (VTO) provides support and guidance for many cutting-edge automotive technologies under development. Research focuses on addressing critical barriers to commercializing higher efficiency, very low emissions advanced internal combustion engines for passenger and commercial vehicles.

  14. FY2015 Advanced Combustion Engine Annual Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Gurpreet [Vehicle Technologies Office, Washington, DC (United States); Gravel, Roland M. [Vehicle Technologies Office, Washington, DC (United States); Howden, Kenneth C. [Vehicle Technologies Office, Washington, DC (United States); Breton, Leo [Vehicle Technologies Office, Washington, DC (United States)

    2016-03-25

    The Advanced Combustion Engine research and development (R&D) subprogram within the DOE Vehicle Technologies Office (VTO) provides support and guidance for many cutting-edge automotive technologies under development. Research focuses on addressing critical barriers to commercializing higher efficiency, very low emissions advanced internal combustion engines for passenger and commercial vehicles.

  15. Diesel combustion: an integrated view combining laser diagnostics, chemical kinetics, and empirical validation

    Energy Technology Data Exchange (ETDEWEB)

    Akinyami, O C; Dec, J E; Durrett, R P; Flynn, P F; Hunter, G L; Loye, A O; Westbrook, C

    1999-02-01

    This paper proposes a structure for the diesel combustion process based on a combination of previously published and new results. Processes are analyzed with proven chemical kinetic models and validated with data from production-like direct injection diesel engines. The analysis provides new insight into the ignition and particulate formation processes, which combined with laser diagnostics, delineates the two-stage nature of combustion in diesel engines. Data are presented to quantify events occurring during the ignition and initial combustion processes that form soot precursors. A framework is also proposed for understanding the heat release and emission formation processes.

  16. Studies on orange oil methyl ester in diesel engine with hemispherical and toroidal combustion chamber

    Directory of Open Access Journals (Sweden)

    Karthickeyan Viswanathan

    2016-01-01

    Full Text Available An investigation has been made to compare the emission characteristics of 20% orange oil methyl ester and 80% diesel in volumetric basis with Neat diesel in hemispherical combustion chamber and toroidal combustion chamber. Non-edible orange oil is selected and utilized to prepare alternative fuel to be utilized in Diesel engine. The traditional method of transestrification is employed for preparation orange oil methyl ester. The chemical properties of prepared methyl ester were determined using fouriertransform infrared spectroscopy method. Further its fuel properties were found based on American Society for Testing and Materials standards and compared with Neat diesel fuel properties. A compression ignition engine with electrical dynamometer test rig with gas analyzer has been used. It is observed that 1% of NOx and 4% of HC emission reduced in toroidal combustion chamber engine. However, smoke emission is found to be lower in hemispherical combustion chamber engine.

  17. Knock prediction for dual fuel engines by using a simplified combustion model

    Institute of Scientific and Technical Information of China (English)

    费少梅; 刘震涛; 严兆大

    2003-01-01

    The present work used a methane-air mixture chemical kinetics scheme consisting of 119 elementary reaction steps and 41 chemical species to develop a simplified combustion model for prediction of the knock in dual fuel engines. Calculated values by the model for natural gas operation showed good agreement with corresponding experimental values over a broad range of operating conditions.

  18. Chemical Looping Combustion Reactions and Systems

    Energy Technology Data Exchange (ETDEWEB)

    Sarofim, Adel; Lighty, JoAnn; Smith, Philip; Whitty, Kevin; Eyring, Edward; Sahir, Asad; Alvarez, Milo; Hradisky, Michael; Clayton, Chris; Konya, Gabor; Baracki, Richard; Kelly, Kerry

    2011-07-01

    Chemical Looping Combustion (CLC) is one promising fuel-combustion technology, which can facilitate economic CO2 capture in coal-fired power plants. It employs the oxidation/reduction characteristics of a metal, or oxygen carrier, and its oxide, the oxidizing gas (typically air) and the fuel source may be kept separate. This work focused on two classes of oxygen carrier, one that merely undergoes a change in oxidation state, such as Fe3O4/Fe2O3 and one that is converted from its higher to its lower oxidation state by the release of oxygen on heating, i.e., CuO/Cu2O. This topical report discusses the results of four complementary efforts: (1) the development of process and economic models to optimize important design considerations, such as oxygen carrier circulation rate, temperature, residence time; (2) the development of high-performance simulation capabilities for fluidized beds and the collection, parameter identification, and preliminary verification/uncertainty quantification (3) the exploration of operating characteristics in the laboratory-scale bubbling bed reactor, with a focus on the oxygen carrier performance, including reactivity, oxygen carrying capacity, attrition resistance, resistance to deactivation, cost and availability (4) the identification of mechanisms and rates for the copper, cuprous oxide, and cupric oxide system using thermogravimetric analysis.

  19. Progress of energy system with chemical-looping combustion

    Institute of Scientific and Technical Information of China (English)

    JIN HongGuang; HONG Hui; HAN Tao

    2009-01-01

    Chemical-looping combustion with zero energy penalty of CO2 separation is a significant breakthrough in resolving energy and environment problems for power generation systems. This paper summarizes the research on energy systems with chemical-looping combustion conducted in recent years, discloses the underlying mechanism of energy release of chemical-looping combustion, describes the trends of the key technology development, and presents the proposed chemicaMooping combustion thermal cycles. This paper may provide a new direction to the synthesis of the next-generation energy system compatible with environment.

  20. Operation of fixed-bed chemical looping combustion

    NARCIS (Netherlands)

    Kimball, E.; Hamers, H.P.; Cobden, P.D.; Gallucci, F.; Sint Annaland, M. van

    2013-01-01

    Chemical Looping Combustion is an alternative technology for CO2 capture. While most systems utilize dual circulating fluidized-beds, this work shows that fixed-bed Chemical Looping Combustion is a feasible configuration for this technology. The inherent separation of the CO2 from the depleted air s

  1. Plasma Assisted Combustion: Fundamental Studies and Engine Applications

    Science.gov (United States)

    Lefkowitz, Joseph K.

    Successful and efficient ignition in short residence time environments or ultra-lean mixtures is a key technological challenge for the evolution of advanced combustion devices in terms of both performance and efficiency. To meet this challenge, interest in plasma assisted combustion (PAC) has expanded over the past 20 years. However, understanding of the underlying physical processes of ignition by plasma discharge remains elementary. In order to shed light on the key processes involved, two main thrusts of research were undertaken in this dissertation. First, demonstration of the applicability of plasma discharges in engines and engine-like environments was carried out using a microwave discharge and a nanosecond repetitively pulsed discharge in an internal combustion engine and a pulsed detonation engine, respectively. Major conclusions include the extension of lean ignition limits for both engines, significant reduction of ignition time for mixtures with large minimum ignition energy, and the discovery of the inter-pulse coupling effect of nanosecond repetitively pulsed (NRP) discharges at high frequency. In order to understand the kinetic processes that led to these improvements, the second thrust of research directly explored the chemical kinetic processes of plasma discharges with hydrocarbon fuels. For this purpose, a low pressure flow reactor with a NRP dielectric barrier discharge cell was assembled. The discharge cell was fitted with a Herriott type multipass mirror arrangement, which allowed quantitative laser absorption spectroscopy to be performed in situ during the plasma discharge. Experiments on methane and ethylene mixtures with oxygen, argon, and helium revealed the importance of low temperature oxidation pathways in PAC. In particular, oxygen addition reactions were shown to be of primary importance in the oxidation of these small hydrocarbons in the temperature range of 300-600 K. Kinetic modeling tools, including both a coupled plasma and

  2. Internal combustion engine for natural gas compressor operation

    Energy Technology Data Exchange (ETDEWEB)

    Hagen, Christopher; Babbitt, Guy

    2016-12-27

    This application concerns systems and methods for compressing natural gas with an internal combustion engine. In a representative embodiment, a method is featured which includes placing a first cylinder of an internal combustion engine in a compressor mode, and compressing a gas within the first cylinder, using the cylinder as a reciprocating compressor. In some embodiments a compression check valve system is used to regulate pressure and flow within cylinders of the engine during a compression process.

  3. Rotary-piston internal combustion engine. Rotationskolbenbrennkraftmaschine

    Energy Technology Data Exchange (ETDEWEB)

    Eiermann, D.

    1991-08-08

    Rotary-piston internal combustion engine in trochoidal design with a slide bearing piston which is controlled by a synchronous gear. The gear is covered by an insert unit which is screwed at the eccentric. The insert unit seals the synchronous gear from the remaining machine parts; it has a hollow cylinder which covers the hollow gear of the synchronous gear and is eccentric to the eccentric shaft; it is sealed with a sealing ring from a shoulder of the piston. A further hollow cylinder is coaxial to the eccentric shaft; it surrounds the mount part with a clearance for the pinion; it projects into the boring at the side of the shaft and it is sealed by a sealing ring from the boring. An annular space which is sealed from the remaining engine rooms is on the other side of the bearing. The oil which escapes from the bearing is led from this annular space through the cooling rooms of the piston to the synchronous gear. The oil is carried off into a drain channel through the space which is formed by the coaxial hollow cylinder in the sidewall.

  4. Potential of Porous-Media Combustion Technology as Applied to Internal Combustion Engines

    Directory of Open Access Journals (Sweden)

    Miroslaw Weclas

    2010-01-01

    Full Text Available The paper summarizes the knowledge concerning porous media combustion techniques as applied in engines. One of most important reasons of this review is to introduce this still not well known technology to researchers doing with internal combustion engine processes, thermal engines, reactor thermodynamics, combustion, and material science. The paper gives an overview of possible applications of a highly porous open cell structures to in-cylinder processes. This application means utilization of unique features of porous media for supporting engine processes, especially fuel distribution in space, vaporization, mixing with air, heat recuperation, ignition and combustion. There are three ways for applying porous medium technology to engines: support of individual processes, support of homogeneous combustion process (catalytic and non-catalytic with temperature control, and utilization of the porous structure as a heat capacitor only. In the first type of application, the porous structure may be utilized for fuel vaporization and improved fuel distribution in space making the mixture more homogeneous in the combustion chamber. Extension of these processes to mixture formation and ignition inside a combustion reactor allows the realization of a homogeneous and a nearly zero emissions level combustion characterized by a homogeneous temperature field at reduced temperature level.

  5. Signal Processing Methods for Liquid Rocket Engine Combustion Spontaneous Stability and Rough Combustion Assessments

    Science.gov (United States)

    Kenny, R. Jeremy; Casiano, Matthew; Fischbach, Sean; Hulka, James R.

    2012-01-01

    Liquid rocket engine combustion stability assessments are traditionally broken into three categories: dynamic stability, spontaneous stability, and rough combustion. This work focuses on comparing the spontaneous stability and rough combustion assessments for several liquid engine programs. The techniques used are those developed at Marshall Space Flight Center (MSFC) for the J-2X Workhorse Gas Generator program. Stability assessment data from the Integrated Powerhead Demonstrator (IPD), FASTRAC, and Common Extensible Cryogenic Engine (CECE) programs are compared against previously processed J-2X Gas Generator data. Prior metrics for spontaneous stability assessments are updated based on the compilation of all data sets.

  6. Numerical Studies on Controlling Gaseous Fuel Combustion by Managing the Combustion Process of Diesel Pilot Dose in a Dual-Fuel Engine

    Directory of Open Access Journals (Sweden)

    Mikulski Maciej

    2015-06-01

    Full Text Available Protection of the environment and counteracting global warming require finding alternative sources of energy. One of the methods of generating energy from environmentally friendly sources is increasing the share of gaseous fuels in the total energy balance. The use of these fuels in compression-ignition (CI engines is difficult due to their relatively high autoignition temperature. One solution for using these fuels in CI engines is operating in a dualfuel mode, where the air and gas mixture is ignited with a liquid fuel dose. In this method, a series of relatively complex chemical processes occur in the engine's combustion chamber, related to the combustion of individual fuel fractions that interact with one another. Analysis of combustion of specific fuels in this type of fuel injection to the engine is difficult due to the fact that combustion of both fuel fractions takes place simultaneously. Simulation experiments can be used to analyse the impact of diesel fuel combustion on gaseous fuel combustion. In this paper, we discuss the results of simulation tests of combustion, based on the proprietary multiphase model of a dual-fuel engine. The results obtained from the simulation allow for analysis of the combustion process of individual fuels separately, which expands the knowledge obtained from experimental tests on the engine.

  7. Survey of Greener Ignition and Combustion Systems for Internal Combustion Engines

    OpenAIRE

    Luo, Wuqiao; Li, Yun; Tian, Zhong; Gao, Bo; Tong, Ling; Wang, Houjun; Zeng, Baoqing

    2015-01-01

    The spark and compression ignition principles of, petrol and diesel internal combustion engines (ICEs) have, not advanced for a century. These do not lead to complete, combustion and hence result in high exhaust emission and, low energy efficiency. This paper presents a comprehensive survey on the attempts and developments of greener ignition, and combustion systems for ICEs and points out that, homogeneous charge microwave ignition (HCMI) holds the, key to a perfect solution. Increasing the ...

  8. Backfire prediction in a manifold injection hydrogen internal combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xing-hua; Liu, Fu-shui; Zhou, Lei; Sun, Bai-gang [School of Mechanical and Vehicular Engineering, Beijing Institute of Technology, Beijing 100081 (China); Schock, Harold J. [Engine Research Laboratory, Michigan State University, East Lansing, MI (United States)

    2008-07-15

    Hydrogen internal combustion engine (H2ICE) easily occur inlet manifold backfire and other abnormal combustion phenomena because of the low ignition energy, wide flammability range and rapid combustion speed of hydrogen. In this paper, the effect of injection timing on mixture formation in a manifold injection H2ICE was studied in various engine speed and equivalence ratio by CFD simulation. It was concluded that H2ICE of manifold injection have an limited injection end timing in order to prevent backfire in the inlet manifold. Finally, the limit of injection end timing of the H2ICE was proposed and validated by engine experiment. (author)

  9. Multi-dimensional modeling of the application of catalytic combustion to homogeneous charge compression ignition engine

    Science.gov (United States)

    Zeng, Wen; Xie, Maozhao

    2006-12-01

    The detailed surface reaction mechanism of methane on rhodium catalyst was analyzed. Comparisons between numerical simulation and experiments showed a basic agreement. The combustion process of homogeneous charge compression ignition (HCCI) engine whose piston surface has been coated with catalyst (rhodium and platinum) was numerically investigated. A multi-dimensional model with detailed chemical kinetics was built. The effects of catalytic combustion on the ignition timing, the temperature and CO concentration fields, and HC, CO and NOx emissions of the HCCI engine were discussed. The results showed the ignition timing of the HCCI engine was advanced and the emissions of HC and CO were decreased by the catalysis.

  10. Development of Kinetic Mechanisms for Next-Generation Fuels and CFD Simulation of Advanced Combustion Engines

    Energy Technology Data Exchange (ETDEWEB)

    Pitz, William J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); McNenly, Matt J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Whitesides, Russell [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Mehl, Marco [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Killingsworth, Nick J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Westbrook, Charles K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-12-17

    Predictive chemical kinetic models are needed to represent next-generation fuel components and their mixtures with conventional gasoline and diesel fuels. These kinetic models will allow the prediction of the effect of alternative fuel blends in CFD simulations of advanced spark-ignition and compression-ignition engines. Enabled by kinetic models, CFD simulations can be used to optimize fuel formulations for advanced combustion engines so that maximum engine efficiency, fossil fuel displacement goals, and low pollutant emission goals can be achieved.

  11. Parametric optimization of a new hybrid pneumatic-combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Higelin, P.; Vasile, I.; Charlet, A.; Chamaillard, Y. [Universite d' Orleans, LME-ESEM, Orleans (France)

    2004-06-01

    Although internal combustion engines display high overall maximum global efficiencies, this potential cannot be fully exploited in automotive applications: in real conditions, the average engine load (and thus efficiency) is quite low and the kinetic energy during a braking phase is lost. One solution to this problem is to switch to a new hybrid pneumatic-combustion engine concept, which is able to store energy in the form of compressed air. This energy can be issued from a braking phase or from a combustion phase at low power. The potential energy from the air tank can then be restored to start the engine, use the stored air to drive the engine as a pneumatic motor at low load or charge the engine at full load. Optimization of the compressed air tank maximum pressure and volume as well as the operating mode switching strategy provides an improvement in terms of fuel economy as high as 31 per cent if combined with engine downsizing. (Author)

  12. Combustion Characteristics of Liquid Normal Alkane Fuels in a Model Combustor of Supersonic Combustion Ramjet Engine

    Science.gov (United States)

    今村, 宰; 石川, 雄太; 鈴木, 俊介; 福本, 皓士郎; 西田, 俊介; 氏家, 康成; 津江, 光洋

    Effect of kinds of one-component n-alkane liquid fuels on combustion characteristics was investigated experimentally using a model combustor of scramjet engine. The inlet condition of a model combustor is 2.0 of Mach number, up to 2400K of total temperature, and 0.38MPa of total pressure. Five kinds of n-alkane are tested, of which carbon numbers are 7, 8, 10, 13, and 16. They are more chemically active and less volatile with an increase of alkane carbon number. Fuels are injected to the combustor in the upstream of cavity with barbotage nitrogen gas and self-ignition performance was investigated. The result shows that self-ignition occurs with less equivalence ratio when alkane carbon number is smaller. This indicates that physical characteristic of fuel, namely volatile of fuel, is dominant for self-ignition behavior. Effect on flame-holding performance is also examined with adding pilot hydrogen and combustion is kept after cutting off pilot hydrogen with the least equivalence ratio where alkane carbon number is from 8 to 10. These points are discussed qualitatively from the conflict effect of chemical and physical properties on alkane carbon number.

  13. Fundamentals of chemical reaction engineering

    CERN Document Server

    Davis, Mark E

    2012-01-01

    Appropriate for a one-semester undergraduate or first-year graduate course, this text introduces the quantitative treatment of chemical reaction engineering. It covers both homogeneous and heterogeneous reacting systems and examines chemical reaction engineering as well as chemical reactor engineering. The authors take a chemical approach, helping students develop an intuitive feeling for concepts, rather than an engineering approach, which tends to overlook the inner workings of systems and objects.Each chapter contains numerous worked-out problems and real-world vignettes involving commercia

  14. Modelling of Combustion and Pollutant Formation in a Large, Two-Stroke Marine Diesel Engine using Integrated CFD-Skeletal Chemical Mechanism

    DEFF Research Database (Denmark)

    Pang, Kar Mun; Karvounis, Nikolas; Schramm, Jesper

    , liftoff lengths and averaged soot volume fraction (SVF) with respect to the change of ambient pressure captured using the model agree reasonably well with the measurement, apart from those at the low pressure condition. Numerical models are subsequently validated against experimental combustion...

  15. Combustion characteristics of turbo charged DISI-engines

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmeyer, Henrik

    2012-07-01

    In spite of progress in the development of alternative powertrain systems and energy sources, the internal combustion and all its derivates still are and will be the main powertrain for automobiles. In SI-engines, several approaches compete with each other like the controlled auto ignition (CAI or HCCI), throttle-free load control using variable valvetrains, stratified mixture formation with lean engine operation or highly turbo charged downsizing concepts all combined with gasoline direct injection. The presented work makes a contribution for a deeper understanding of the combustion process of a turbo charged direct injection engine operating with external EGR as well as lean stratified mixture. Using detailed test bench investigations and introducing a new optical measurement tool, the combustion process is described in detail focusing on the occurrence of non-premixed combustion phenomena. The influence of engine parameters like global and local air-/fuel ratio, external EGR and fuel rail pressure as well as the influence of fuel parameters are discussed giving a characterization of the combustion process of stratified engine operation. Furthermore, the influences of non-inert exhaust gas components on engine knock tendency are investigated using external EGR with an EGR catalyst. Opposing the results to numerical analysis, combustion characteristics of turbo charged DISI-engines are presented. (orig.)

  16. International evaluation of the programme on engine-related combustion

    Energy Technology Data Exchange (ETDEWEB)

    Arcoumanis, D. [Imperial College, London (United Kingdom); Greenhalgh, D. [Cranfield Univ. (United Kingdom); Magnusson, B.F. [Norwegian Univ. of Science and Technology, Trondheim (Norway); Peters, N. [Institut fuer Technische Mechanik, RWTH Aachen (Germany)

    1996-11-01

    The 12 projects in the engine related combustion programme cover the entire range from fundamental and theoretical aspects of combustion to more applied subjects such as engine control. The common denominator in the programme clearly is the internal combustion engine, both the reciprocating as well as the gas turbine engine. Such a large coverage by a relatively small number of projects necessarily leads to an isolation of some of the projects in terms of their subject as well as the methodology that is used. On the other hand, all the research areas of interest in combustion technology are represented by at least one of the projects. These are: mathematical and numerical methods in combustion; modelling of turbulent combustion; laser diagnostics of flows with combustion; studies of engine performance and their control; semi-empirical model development for practical applications. As a conclusion, the evaluation committee believes that the programme is well balanced between fundamental and applied projects. It covers the entire range of modern methodologies that are used on the international level and thereby contributes to the application and further development of these research tools in Sweden

  17. Thermodynamic Simulation of a Hybrid Pneumatic-Combustion Engine Concept

    Directory of Open Access Journals (Sweden)

    Yann Chamaillard

    2002-03-01

    Full Text Available Although internal combustion engines display high overall maximum global efficiencies, this potential cannot be fully exploited in automotive applications: in real conditions, the average engine load (and thus efficiency is quite low and the kinetic energy during a braking phase is lost. This work presents a new hybrid pneumatic-combustion engine and the associated thermodynamic cycles, which is able to store energy in the form of compressed air. This energy can be issued from a braking phase or from a combustion phase at low power. The potential energy from the air tank can then be restored to start the engine, or charge the engine at full load. The regenerative breaking and the suppression of the idling phases could provide an improvement in terms of fuel economy as high as 15% or more if combined with engine downsizing.

  18. Surrogate fuel formulation for light naphtha combustion in advanced combustion engines

    KAUST Repository

    Ahmed, Ahfaz

    2015-03-30

    Crude oil once recovered is further separated in to several distinct fractions to produce a range of energy and chemical products. One of the less processed fractions is light naphtha (LN), hence they are more economical to produce than their gasoline and diesel counterparts. Recent efforts have demonstrated usage of LN as transportation fuel for internal combustion engines with slight modifications. In this study, a multicomponent surrogate fuel has been developed for light naphtha fuel using a multi-variable nonlinear constrained optimization scheme. The surrogate, consisting of palette species n-pentane, 2-methylhexane, 2-methylbutane, n-heptane and toluene, was validated against the LN using ignition quality tester following ASTM D6890 methodology. Comparison of LN and the surrogate fuel demonstrated satisfactory agreement.

  19. A numerical study of turbulent combustion characteristics in a combustion chamber of a scramjet engine

    Institute of Scientific and Technical Information of China (English)

    LEE; ChunHian

    2010-01-01

    3D numerical simulation of flow fields in a combustion chamber of a scramjet engine using an SST turbulence model with an explicit compressibility correction was performed and the results were compared to the experimental results.The characteristics of the turbulent combustion flow fields were analyzed via the numerical results and presented.In order to identify the mechanisms of turbulent combustion in supersonic flows,the evolutions of governing dimensionless parameters in the flow fields were investigated based on the theory of combustion and the available numerical results.It was found that the supersonic combustion takes place in the region of fully developed turbulence and that the strongest effects of turbulence and combustion processes appear in the vicinity of the injector.The unsteady effects and the local flame extinction phenomenon induced by turbulent flows were found to be negligibly small,and the steady flamelet approximation will hold for practical applications.

  20. Determination of combustion parameters using engine crankshaft speed

    Science.gov (United States)

    Taglialatela, F.; Lavorgna, M.; Mancaruso, E.; Vaglieco, B. M.

    2013-07-01

    Electronic engine controls based on real time diagnosis of combustion process can significantly help in complying with the stricter and stricter regulations on pollutants emissions and fuel consumption. The most important parameter for the evaluation of combustion quality in internal combustion engines is the in-cylinder pressure, but its direct measurement is very expensive and involves an intrusive approach to the cylinder. Previous researches demonstrated the direct relationship existing between in-cylinder pressure and engine crankshaft speed and several authors tried to reconstruct the pressure cycle on the basis of the engine speed signal. In this paper we propose the use of a Multi-Layer Perceptron neural network to model the relationship between the engine crankshaft speed and some parameters derived from the in-cylinder pressure cycle. This allows to have a non-intrusive estimation of cylinder pressure and a real time evaluation of combustion quality. The structure of the model and the training procedure is outlined in the paper. A possible combustion controller using the information extracted from the crankshaft speed information is also proposed. The application of the neural network model is demonstrated on a single-cylinder spark ignition engine tested in a wide range of speeds and loads. Results confirm that a good estimation of some combustion pressure parameters can be obtained by means of a suitable processing of crankshaft speed signal.

  1. Job Prospects for Chemical Engineers.

    Science.gov (United States)

    Basta, Nicholas

    1985-01-01

    The job situation for new chemical engineers with bachelor's degrees is continuing to reflect the gradual improvement that began in 1983. However, companies are looking for graduates with technical expertise as well as marketing, sales, or communications skills. Smaller classes may lead to shortages of chemical engineering graduates in the future.…

  2. Teaching Chemical Engineers about Teaching

    Science.gov (United States)

    Heath, Daniel E.; Hoy, Mary; Rathman, James F.; Rohdieck, Stephanie

    2013-01-01

    The Chemical and Biomolecular Engineering Department at The Ohio State University in collaboration with the University Center for the Advancement of Teaching developed the Chemical Engineering Mentored Teaching Experience. The Mentored Teaching Experience is an elective for Ph.D. students interested in pursuing faculty careers. Participants are…

  3. Real time identification of the internal combustion engine combustion parameters based on the vibration velocity signal

    Science.gov (United States)

    Zhao, Xiuliang; Cheng, Yong; Wang, Limei; Ji, Shaobo

    2017-03-01

    Accurate combustion parameters are the foundations of effective closed-loop control of engine combustion process. Some combustion parameters, including the start of combustion, the location of peak pressure, the maximum pressure rise rate and its location, can be identified from the engine block vibration signals. These signals often include non-combustion related contributions, which limit the prompt acquisition of the combustion parameters computationally. The main component in these non-combustion related contributions is considered to be caused by the reciprocating inertia force excitation (RIFE) of engine crank train. A mathematical model is established to describe the response of the RIFE. The parameters of the model are recognized with a pattern recognition algorithm, and the response of the RIFE is predicted and then the related contributions are removed from the measured vibration velocity signals. The combustion parameters are extracted from the feature points of the renovated vibration velocity signals. There are angle deviations between the feature points in the vibration velocity signals and those in the cylinder pressure signals. For the start of combustion, a system bias is adopted to correct the deviation and the error bound of the predicted parameters is within 1.1°. To predict the location of the maximum pressure rise rate and the location of the peak pressure, algorithms based on the proportion of high frequency components in the vibration velocity signals are introduced. Tests results show that the two parameters are able to be predicted within 0.7° and 0.8° error bound respectively. The increase from the knee point preceding the peak value point to the peak value in the vibration velocity signals is used to predict the value of the maximum pressure rise rate. Finally, a monitoring frame work is inferred to realize the combustion parameters prediction. Satisfactory prediction for combustion parameters in successive cycles is achieved, which

  4. Operation Evaluation Method for Marine Turbine Combustion Engines in Terms of Energetics

    Directory of Open Access Journals (Sweden)

    Dzida Marek

    2016-12-01

    Full Text Available An evaluation proposal (quantitative determination of any combustion turbine engine operation has been presented, wherein the impact energy occurs at a given time due to Energy conversion. The fact has been taken into account that in this type of internal combustion engines the energy conversion occurs first in the combustion chambers and in the spaces between the blade of the turbine engine. It was assumed that in the combustion chambers occurs a conversion of chemical energy contained in the fuel-air mixture to the internal energy of the produced exhaust gases. This form of energy conversion has been called heat. It was also assumed that in the spaces between the blades of the rotor turbine, a replacement occurs of part of the internal energy of the exhaust gas, which is their thermal energy into kinetic energy conversion of its rotation. This form of energy conversion has been called the work. Operation of the combustion engine has been thus interpreted as a transmission of power receivers in a predetermined time when there the processing and transfer in the form (means of work and heat occurs. Valuing the operation of this type of internal combustion engines, proposed by the authors of this article, is to determine their operation using physical size, which has a numerical value and a unit of measurement called joule-second [joule x second]. Operation of the combustion turbine engine resulting in the performance of the turbine rotor work has been presented, taking into account the fact that the impeller shaft is connected to the receiver, which may be a generator (in the case of one-shaft engine or a propeller of the ship (in the case of two or three shaft engine.

  5. Chemical Looping Combustion Reactions and Systems

    Energy Technology Data Exchange (ETDEWEB)

    Sarofim, Adel; Lighty, JoAnn; Smith, Philip; Whitty, Kevin; Eyring, Edward; Sahir, Asad; Alvarez, Milo; Hradisky, Michael; Clayton, Chris; Konya, Gabor; Baracki, Richard; Kelly, Kerry

    2014-03-01

    Chemical Looping Combustion (CLC) is one promising fuel-combustion technology, which can facilitate economic CO{sub 2} capture in coal-fired power plants. It employs the oxidation/reduction characteristics of a metal, or oxygen carrier, and its oxide, the oxidizing gas (typically air) and the fuel source may be kept separate. This topical report discusses the results of four complementary efforts: (5.1) the development of process and economic models to optimize important design considerations, such as oxygen carrier circulation rate, temperature, residence time; (5.2) the development of high-performance simulation capabilities for fluidized beds and the collection, parameter identification, and preliminary verification/uncertainty quantification; (5.3) the exploration of operating characteristics in the laboratoryscale bubbling bed reactor, with a focus on the oxygen carrier performance, including reactivity, oxygen carrying capacity, attrition resistance, resistance to deactivation, cost and availability; and (5.4) the identification of kinetic data for copper-based oxygen carriers as well as the development and analysis of supported copper oxygen carrier material. Subtask 5.1 focused on the development of kinetic expressions for the Chemical Looping with Oxygen Uncoupling (CLOU) process and validating them with reported literature data. The kinetic expressions were incorporated into a process model for determination of reactor size and oxygen carrier circulation for the CLOU process using ASPEN PLUS. An ASPEN PLUS process model was also developed using literature data for the CLC process employing an iron-based oxygen carrier, and the results of the process model have been utilized to perform a relative economic comparison. In Subtask 5.2, the investigators studied the trade-off between modeling approaches and available simulations tools. They quantified uncertainty in the high-performance computing (HPC) simulation tools for CLC bed applications. Furthermore

  6. Harmonic components of cylinder pressure variation and their characteristics for combustion noise in internal combustion engines

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S.R.; Miyamoto, Noboru; Murayama, Tadashi

    1987-10-31

    Combustion noise is a serious problem in internal combustion engines, especially diesel engines. Although the cylinder pressure variation is easily visible tool to evaluate the combustion noise and thermal efficiency, the exciting force in engine combustion noise has not been completely determined. Cylinder pressure variation for different combustion behaviors and their harmonic components were calculated and an attempt was made to correlate the various components. It was found that the logarithmic harmonic components of cylinder pressure variations, the cylinder pressure level (CPL) can be described by a function with four variables, the values of cylinder pressure variation. The results of this paper is summarized as follows: 1) A relationship was established between CPL and four characteristic values describing the cylinder pressure and variation diagram. 2) Harmonic components of cylinder pressure variations are described by a linear function with four variables and four characteristic values. 3) In this case, the coefficients of the four variables depend solely on the order of engine revolutions and are independent of combustion behavior and engine operating conditions. (13 figs, 7 refs)

  7. Study of Second Generation Biofuels in Internal Combustion Engines

    Energy Technology Data Exchange (ETDEWEB)

    Kannan, Dhandapani

    2012-07-01

    fuel, vis-a-vis neat diesel fuel (DF). The CO, THC, smoke and TPM emissions were reduced significantly, while NOx emissions were somewhat higher with BD blended fuels compared to neat FT fuel. The reductions in CO, THC, smoke and TPM emissions with BD blends were mainly due to the oxygen content in the BD blended fuel, while the increases in NOx emissions with BD fuels were due to advances in injection timing, higher percentages of fatty acids with double bonds in the carbon chain and higher heat release in the pre-mixed combustion. Secondly, a four-stroke, single-cylinder, naturally-aspirated (NA), direct-injection (DI) diesel engine with 8 BHP at 1500 rpm coupled with water-cooled, eddy current dynamometer was used for the experiments. Ethanol (5% by volume) was injected into the intake manifold by the port injection method with the assistance of a mechanical fuel injection pump. Therefore, the volumetric blending percentages of ethanol, BD and diesel fuels (E:D:JME) are (0:100:0), (5:95:0), (5:75:20), (5:55:40), (5:35:60), (5:15:80) (5:0:95) and (0:0:100) respectively. Ethanol pre-mixed with intake air, assisted in improving combustion in both diesel and the JME blends. The addition of ethanol to high-viscosity Jatropha methyl ester (JME) through port injection is investigated in order to determine its effect on the fuels viscosity and thereby on the diesel engine performance. In addition to viscosity alteration, the impact of ethanol addition on combustion characteristics such as combustion duration, ignition delay and emissions levels from diesel engines fuelled with blends of ethanol, diesel and JME was studied in particular. It was found that blending of oxygenated fuels with diesel modifies the chemical structure and physical properties which in turn, alter the engines operating conditions, combustion parameters and emissions levels. However, the injection of only 5% ethanol through port injection allows for up to 25% blending of diesel with biofuels, while

  8. FY 2007 Progress Report for Advanced Combustion Engine Technologies

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2007-12-01

    Advanced combustion engines have great potential for achieving dramatic energy efficiency improvements in light-duty vehicle applications, where it is suited to both conventional and hybrid- electric powertrain configurations. Light-duty vehicles with advanced combustion engines can compete directly with gasoline engine hybrid vehicles in terms of fuel economy and consumer-friendly driving characteristics; also, they are projected to have energy efficiencies that are competitive with hydrogen fuel cell vehicles when used in hybrid applications.Advanced engine technologies being researched and developed by the Advanced Combustion Engine R&D Sub-Program will also allow the use of hydrogen as a fuel in ICEs and will provide an energy-efficient interim hydrogen-based powertrain technology during the transition to hydrogen/fuelcell-powered transportation vehicles.

  9. Cleaner combustion developing detailed chemical kinetic models

    CERN Document Server

    Battin-Leclerc, Frédérique; Blurock, Edward

    2013-01-01

    This overview compiles the on-going research in Europe to enlarge and deepen the understanding of the reaction mechanisms and pathways associated with the combustion of an increased range of fuels. Focus is given to the formation of a large number of hazardous minor pollutants and the inability of current combustion models to predict the  formation of minor products such as alkenes, dienes, aromatics, aldehydes and soot nano-particles which have a deleterious impact on both the environment and on human health. Cleaner Combustion describes, at a fundamental level, the reactive chemistry of min

  10. The Combination of Internal-Combustion Engine and Gas Turbine

    Science.gov (United States)

    Zinner, K.

    1947-01-01

    While the gas turbine by itself has been applied in particular cases for power generation and is in a state of promising development in this field, it has already met with considerable success in two cases when used as an exhaust turbine in connection with a centrifugal compressor, namely, in the supercharging of combustion engines and in the Velox process, which is of particular application for furnaces. In the present paper the most important possibilities of combining a combustion engine with a gas turbine are considered. These "combination engines " are compared with the simple gas turbine on whose state of development a brief review will first be given. The critical evaluation of the possibilities of development and fields of application of the various combustion engine systems, wherever it is not clearly expressed in the publications referred to, represents the opinion of the author. The state of development of the internal-combustion engine is in its main features generally known. It is used predominantly at the present time for the propulsion of aircraft and road vehicles and, except for certain restrictions due to war conditions, has been used to an increasing extent in ships and rail cars and in some fields applied as stationary power generators. In the Diesel engine a most economical heat engine with a useful efficiency of about 40 percent exists and in the Otto aircraft engine a heat engine of greatest power per unit weight of about 0.5 kilogram per horsepower.

  11. Development of High Efficiency Clean Combustion Engine Designs for Spark-Ignition and Compression-Ignition Internal Combustion Engines

    Energy Technology Data Exchange (ETDEWEB)

    Marriott, Craig; Gonzalez, Manual; Russell, Durrett

    2011-06-30

    This report summarizes activities related to the revised STATEMENT OF PROJECT OBJECTIVES (SOPO) dated June 2010 for the Development of High-Efficiency Clean Combustion engine Designs for Spark-Ignition and Compression-Ignition Internal Combustion Engines (COOPERATIVE AGREEMENT NUMBER DE-FC26-05NT42415) project. In both the spark- (SI) and compression-ignition (CI) development activities covered in this program, the goal was to develop potential production-viable internal combustion engine system technologies that both reduce fuel consumption and simultaneously met exhaust emission targets. To be production-viable, engine technologies were also evaluated to determine if they would meet customer expectations of refinement in terms of noise, vibration, performance, driveability, etc. in addition to having an attractive business case and value. Prior to this activity, only proprietary theoretical / laboratory knowledge existed on the combustion technologies explored The research reported here expands and develops this knowledge to determine series-production viability. Significant SI and CI engine development occurred during this program within General Motors, LLC over more than five years. In the SI program, several engines were designed and developed that used both a relatively simple multi-lift valve train system and a Fully Flexible Valve Actuation (FFVA) system to enable a Homogeneous Charge Compression Ignition (HCCI) combustion process. Many technical challenges, which were unknown at the start of this program, were identified and systematically resolved through analysis, test and development. This report documents the challenges and solutions for each SOPO deliverable. As a result of the project activities, the production viability of the developed clean combustion technologies has been determined. At this time, HCCI combustion for SI engines is not considered production-viable for several reasons. HCCI combustion is excessively sensitive to control variables

  12. Numerical simulation of fuel sprays and combustion in a premixed lean diesel engine; Kihaku yokongo diesel kikan ni okeru nenryo funmu to nensho no suchi simulation

    Energy Technology Data Exchange (ETDEWEB)

    Miyamoto, T.; Harada, A.; Sasaki, S.; Shimazaki, N.; Hashizume, T.; Akagawa, H.; Tsujimura, K.

    1997-10-01

    Fuel sprays and combustion in a direct injection Premixed lean Diesel Combustion (PREDIC) engine, which can make smokeless combustion with little NOx emission, is studied numerically. Numerical simulation was carried out by means of KIVA II based computer code with a combustion submodel. The combustion submodel describes the formation of combustible fuel vapor by turbulent mixing and four-step chemical reaction which includes low temperature oxidation. Comparison between computation and experiment shows qualitatively good agreement in terms of heat release rate and NO emission. Computational results indicate that the combustion is significantly influenced by fuel spray characteristics and injection timing to vary NO emission. 10 refs., 8 figs., 1 tab.

  13. DYNAMIC DESIGN OF INTERNAL COMBUSTION ENGINE BLOCK STRUCTURE

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    Several main steps of internal combustion engine block structure dynamic design,such as model set-up,structure dynamic response analysis,optimizing design and vibration and noise control,are discussed for the type of EQ6100 gasoline engine block.

  14. EDWARDS' REFERENCE CYCLE FOR INTERNAL AND EXTERNAL COMBUSTION ENGINES

    Directory of Open Access Journals (Sweden)

    A. E. Piir

    2014-01-01

    Full Text Available Useful physical regularities of a reversible thermodynamic cycle for heat engines have been established in the paper. The engines are using fuel combustion products as a heat source, and the environment - as a heat sink that surpasses Carnot cycle according to efficiency factor.

  15. Engine combustion control at low loads via fuel reactivity stratification

    Science.gov (United States)

    Reitz, Rolf Deneys; Hanson, Reed M; Splitter, Derek A; Kokjohn, Sage L

    2014-10-07

    A compression ignition (diesel) engine uses two or more fuel charges during a combustion cycle, with the fuel charges having two or more reactivities (e.g., different cetane numbers), in order to control the timing and duration of combustion. By appropriately choosing the reactivities of the charges, their relative amounts, and their timing, combustion can be tailored to achieve optimal power output (and thus fuel efficiency), at controlled temperatures (and thus controlled NOx), and with controlled equivalence ratios (and thus controlled soot). At low load and no load (idling) conditions, the aforementioned results are attained by restricting airflow to the combustion chamber during the intake stroke (as by throttling the incoming air at or prior to the combustion chamber's intake port) so that the cylinder air pressure is below ambient pressure at the start of the compression stroke.

  16. Temperature Estimation in the Combustion Chamber of an Internal Combustion Engine

    OpenAIRE

    2012-01-01

    The mathematical model of heat transfer phenomena is considered at the combustion chamber wall in an internal combustion (IC) engine. The mathematical model of proposed phenomena is established with respect to the crank angle. An inverse heat conduction problem is derived at the cylinder wall, and this problem is investigated numerically using Alifanov's regularization method. This problem studied as an optimization problem in which a squared residual functional is minimized with the conjugat...

  17. Experimental combustion analysis of a hsdi diesel engine fuelled with palm oil biodiesel-diesel fuel blends

    OpenAIRE

    JOHN AGUDELO; ELKIN GUTIÉRREZ; PEDRO BENJUMEA

    2010-01-01

    Differences in the chemical nature between petroleum diesel fuels and vegetable oils-based fuels lead to differences in their physical properties affecting the combustion process inside the engine. In this work a detailed combustion diagnosis was applied to a turbocharged automotive diesel engine operating with neat palm oil biodiesel (POB), No. 2 diesel fuel and their blends at 20 and 50% POB by volume (B20 and B50 respectively). To isolate the fuel effect, tests were executed at constant po...

  18. Internal Combustion Engine Powered by Synthesis Gas from Pyrolysed Plastics

    Directory of Open Access Journals (Sweden)

    Chríbik Andrej

    2016-07-01

    Full Text Available The article discusses the application of synthesis gas from pyrolysis of plastics in petrol engine. The appropriate experimental measurements were performed on a combustion engine LGW 702 designated for micro-cogeneration unit. The power parameters, economic parameters in term of brake specific fuel consumption, and internal parameters of the engine were compared to the engine running on the reference fuel - natural gas and synthesis gas. Burning synthesis gas leads to decreased performance by about 5% and to increased mass hourly consumption by 120 %. In terms of burning, synthesis gas has similar properties as natural gas. Compared with [5] a more detailed study has been prepared on the effects of angle of spark advance on the engine torque, giving more detailed assessment of engine cycle variability and considering specification of start and end of combustion in the logarithm p-V diagram.

  19. CFD Studies of Combustion in Direct Injection Single Cylinder Diesel Engine Using Non-Premixed Combustion Model

    Directory of Open Access Journals (Sweden)

    S Gavudhama Karunanidhi

    2014-07-01

    Full Text Available In this study the simulation process of non-premixed combustion in a direct injection single cylinder diesel engine has been described. Direct injection diesel engines are used both in heavy duty vehicles and light duty vehicles. The fuel is injected directly into the combustion chamber. The fuel mixes with the high pressure air in the combustion chamber and combustion occurs. Due to the non-premixed nature of the combustion occurring in such engines, non-premixed combustion model of ANSYS FLUENT 14.5 can be used to simulate the combustion process. A 4-stroke diesel engine corresponds to one fuel injector hole without considering valves was modeled and combustion simulation process was studied. Here two types of combustion chambers were compared. Combustion studies of both chambers:- shallow depth and hemispherical combustion chambers were carried out. Emission characteristics of both combustion chambers had also been carried out. The obtained results are compared. It has been found that hemispherical combustion chamber is more efficient as it produces higher pressure and temperature compared to that of shallow depth combustion chamber. As the temperature increases the formation of NOx emissions and soot formation also get increased.

  20. Numerical Analysis on Combustion Characteristic of Leaf Spring Rotary Engine

    Directory of Open Access Journals (Sweden)

    Yan Zhang

    2015-08-01

    Full Text Available The purpose of this paper is to investigate combustion characteristics for rotary engine via numerical studies. A 3D numerical model was developed to study the influence of several operative parameters on combustion characteristics. A novel rotary engine called, “Leaf Spring Rotary Engine”, was used to illustrate the structure and principle of the engine. The aims are to (1 improve the understanding of combustion process, and (2 quantify the influence of rotational speed, excess air ratio, initial pressure and temperature on combustion characteristics. The chamber space changed with crankshaft rotation. Due to the complexity of chamber volume, an equivalent modeling method was presented to simulate the chamber space variation. The numerical simulations were performed by solving the incompressible, multiphase Unsteady Reynolds-Averaged Navier–Stokes Equations via the commercial code FLUENT using a transport equation-based combustion model; a realizable  turbulence model and finite-rate/eddy-dissipation model were used to account for the effect of local factors on the combustion characteristics.

  1. COMBUSTION SIMULATION IN A SPARK IGNITION ENGINE CYLINDER: EFFECTS OF AIR-FUEL RATIO ON THE COMBUSTION DURATION

    Directory of Open Access Journals (Sweden)

    Nureddin Dinler

    2010-01-01

    Full Text Available Combustion is an important subject of internal combustion engine studies. To reduce the air pollution from internal combustion engines and to increase the engine performance, it is required to increase combustion efficiency. In this study, effects of air/fuel ratio were investigated numerically. An axisymmetrical internal combustion engine was modeled in order to simulate in-cylinder engine flow and combustion. Two dimensional transient continuity, momentum, turbulence, energy, and combustion equations were solved. The k-e turbulence model was employed. The fuel mass fraction transport equation was used for modeling of the combustion. For this purpose a computational fluid dynamics code was developed by using the finite volume method with FORTRAN programming code. The moving mesh was utilized to simulate the piston motion. The developed code simulates four strokes of engine continuously. In the case of laminar flow combustion, Arrhenius type combustion equations were employed. In the case of turbulent flow combustion, eddy break-up model was employed. Results were given for rich, stoichiometric, and lean mixtures in contour graphs. Contour graphs showed that lean mixture (l = 1.1 has longer combustion duration.

  2. Construction of combustion models for rapeseed methyl ester bio-diesel fuel for internal combustion engine applications.

    Science.gov (United States)

    Golovitchev, Valeri I; Yang, Junfeng

    2009-01-01

    Bio-diesel fuels are non-petroleum-based diesel fuels consisting of long chain alkyl esters produced by the transesterification of vegetable oils, that are intended for use (neat or blended with conventional fuels) in unmodified diesel engines. There have been few reports of studies proposing theoretical models for bio-diesel combustion simulations. In this study, we developed combustion models based on ones developed previously. We compiled the liquid fuel properties, and the existing detailed mechanism of methyl butanoate ester (MB, C(5)H(10)O(2)) oxidation was supplemented by sub-mechanisms for two proposed fuel constituent components, C(7)H(16) and C(7)H(8)O (and then, by mp2d, C(4)H(6)O(2) and propyne, C(3)H(4)) to represent the combustion model for rapeseed methyl ester described by the chemical formula, C(19)H(34)O(2) (or C(19)H(36)O(2)). The main fuel vapor thermal properties were taken as those of methyl palmitate C(19)H(36)O(2) in the NASA polynomial form of the Burcat database. The special global reaction was introduced to "crack" the main fuel into its constituent components. This general reaction included 309 species and 1472 reactions, including soot and NO(x) formation processes. The detailed combustion mechanism was validated using shock-tube ignition-delay data under diesel engine conditions. For constant volume and diesel engine (Volvo D12C) combustion modeling, this mechanism could be reduced to 88 species participating in 363 reactions.

  3. New controllable premixed combustion for dimethyl ether engine

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    A new concept of the controllable premixed combustion (CPC) system was proposed for dimethyl ether (DME) to explore a new approach to achieving ultra-low NOX emissions with the zero level of particulate matter exhaust emissions. The DME fuel was injected into the premix chamber by means of the electronically controlled low pressure injection system, then the mixture formation and combustion process were controlled with a control-valve set between the main chamber and the premix chamber. The test bench was constructed based on a single diesel engine. Preliminary studies demonstrated that ultra-low NOX emissions had been realized with zero particulate matter emissions under the optimum specifications of the DME engine, NOX emissions were less than 65 × 10-6. According to the engine combustion analysis, it was found that the control-valve played an important role in the pre-mixture formation and ignition timing.

  4. Study Regarding the Identification of an Internal Combustion Engine

    Directory of Open Access Journals (Sweden)

    Ioan Ruja

    2016-10-01

    Full Text Available The paper presents the results of the scientific investigations performed on an Otto engine. One conducted surveys on the analytic and experimental modelling of the internal combustion engine, considered as automated system element. The results of the analytical study are concretised in the mathematical model of the engine, expressed in the operational. The experimental results are concretised in the indicial response in rotating speed, as well as in the determination of the constants of interest. The investigation methods used in conducting the survey were: experimental identification based on the indicial response of the engine and the analytical identification based on the mathematical models of diverse engine subsystems.

  5. Chemical Pollution from Combustion of Modern Spacecraft Materials

    Science.gov (United States)

    Mudgett, Paul D.

    2013-01-01

    Fire is one of the most critical contingencies in spacecraft and any closed environment including submarines. Currently, NASA uses particle based technology to detect fires and hand-held combustion product monitors to track the clean-up and restoration of habitable cabin environment after the fire is extinguished. In the future, chemical detection could augment particle detection to eliminate frequent nuisance false alarms triggered by dust. In the interest of understanding combustion from both particulate and chemical generation, NASA Centers have been collaborating on combustion studies at White Sands Test Facility using modern spacecraft materials as fuels, and both old and new technology to measure the chemical and particulate products of combustion. The tests attempted to study smoldering pyrolysis at relatively low temperatures without ignition to flaming conditions. This paper will summarize the results of two 1-week long tests undertaken in 2012, focusing on the chemical products of combustion. The results confirm the key chemical products are carbon monoxide (CO), hydrogen cyanide (HCN), hydrogen fluoride (HF) and hydrogen chloride (HCl), whose concentrations depend on the particular material and test conditions. For example, modern aerospace wire insulation produces significant concentration of HF, which persists in the test chamber longer than anticipated. These compounds are the analytical targets identified for the development of new tunable diode laser based hand-held monitors, to replace the aging electrochemical sensor based devices currently in use on the International Space Station.

  6. A Study on the Combustion Performance of Diesel Engines with O2 and CO2 Suction

    Directory of Open Access Journals (Sweden)

    Qinming Tan

    2016-01-01

    Full Text Available Based on the chemical reaction mechanism of fuel combustion, NOx in the diesel emissions is mainly generated from N2 inside the burning environment of engine cylinder. Taking the gas mixture, O2 and CO2, as the intake air, nitrogen-free intake is accessible, and through simulative calculations and experiments, researchers can make a study of the ignition and combustion performances of the engines. Taking a type of “4135ACa” diesel engine as the research object, the study suggested the following: in the environment of O2 and CO2, only when the volume fraction of O2 reaches 45% can the engine be ignited and kept running; engine operation became more steady after its O2 percentage increased to 50%. There is no NOx emission of engine’s nitrogen-free combustion, despite some black particles in the exhaust gas. So, the bottleneck of “NOx-Soot” emission is successfully transformed into how to optimize the combustion performance of engines. Additionally, through simulative calculations, influences of the O2 volume fraction on the nitrogen-free combustion performance have been researched; results suggested that it can help promote the burning efficiency with the increase of O2. When it reached 60%, its heat output in the cylinder has been equal to that under the operation condition of air intake. Therefore, nitrogen-free combustion can be used in some NOx control area, especially to some power plant which worked underwater. The huge gas consumption can be recycled from exhaust gas by closed cycle.

  7. A statistical combustion phase control approach of SI engines

    Science.gov (United States)

    Gao, Jinwu; Wu, Yuhu; Shen, Tielong

    2017-02-01

    In order to maximize the performance of internal combustion engine, combustion phase is usually controlled to track its desired reference. However, suffering from the cyclic variability of combustion, it is difficulty but meaningful to control mean of combustion phase and constrain its variance. As a combustion phase indicator, the location of peak pressure (LPP) is utilized for real-time combustion phase control in this research. The purpose of the proposed method is to ensure the mean of LPP statistically tracks its reference and constrains the standard deviation of LPP distribution. To achieve this, LPP is first calculated based on the cylinder pressure sensor, and its characteristics are analyzed at the steady-state operating condition, then the distribution of LPP is examined online using hypothesis test criterion. On the basis of the presented statistical algorithm, current mean of LPP is applied in the feedback channel for designing spark advance adjustment law, and the stability of closed-loop system is theoretically ensured according to a steady statistical model. Finally, the proposed strategy is verified on a spark ignition gasoline engine.

  8. EXPERIMENTAL INVESTIGATION OF COMBUSTION, PERFORMANCE AND EMISSION CHARACTERISTICS OF DI DIESEL ENGINE UNDER HCCI MODE WITH POROUS MEDIUM COMBUSTION

    Directory of Open Access Journals (Sweden)

    C KANNAN

    2010-08-01

    Full Text Available In recent times, homogeneous combustion has been a proven technology to attain high efficient and low emission engines. Homogenous Charge Compression Ignition (HCCI engines are able to have efficiencies as high as Compression Ignition, Direct Injection (CIDI engines, while producing ultra-low emissions of nitrogen oxides (NOx and particulate matter (PM.HCCI combustion is achieved by controlling the temperature, pressure and composition of the fuel-air mixture so that it spontaneously gets ignited in the combustion chamber. Numeroustechniques such as Variable Exhaust Gas Recirculation (VEGR, ariable Compression Ratio (VCR and Variable Valve Timing (VVT have been proposed to control the homogeneous combustion inside the engine cylinder. Even though these techniques are attractive and having good time response, they are too expensive to afford. This paper investigates the performance, combustion and emission characteristics of a Direct Injection (DI diesel engine under HCCI mode which is established through an effective and affordable technique called Porous Medium Combustion (PMC.

  9. Acceleration of the chemistry solver for modeling DI engine combustion using dynamic adaptive chemistry (DAC) schemes

    Science.gov (United States)

    Shi, Yu; Liang, Long; Ge, Hai-Wen; Reitz, Rolf D.

    2010-03-01

    Acceleration of the chemistry solver for engine combustion is of much interest due to the fact that in practical engine simulations extensive computational time is spent solving the fuel oxidation and emission formation chemistry. A dynamic adaptive chemistry (DAC) scheme based on a directed relation graph error propagation (DRGEP) method has been applied to study homogeneous charge compression ignition (HCCI) engine combustion with detailed chemistry (over 500 species) previously using an R-value-based breadth-first search (RBFS) algorithm, which significantly reduced computational times (by as much as 30-fold). The present paper extends the use of this on-the-fly kinetic mechanism reduction scheme to model combustion in direct-injection (DI) engines. It was found that the DAC scheme becomes less efficient when applied to DI engine simulations using a kinetic mechanism of relatively small size and the accuracy of the original DAC scheme decreases for conventional non-premixed combustion engine. The present study also focuses on determination of search-initiating species, involvement of the NOx chemistry, selection of a proper error tolerance, as well as treatment of the interaction of chemical heat release and the fuel spray. Both the DAC schemes were integrated into the ERC KIVA-3v2 code, and simulations were conducted to compare the two schemes. In general, the present DAC scheme has better efficiency and similar accuracy compared to the previous DAC scheme. The efficiency depends on the size of the chemical kinetics mechanism used and the engine operating conditions. For cases using a small n-heptane kinetic mechanism of 34 species, 30% of the computational time is saved, and 50% for a larger n-heptane kinetic mechanism of 61 species. The paper also demonstrates that by combining the present DAC scheme with an adaptive multi-grid chemistry (AMC) solver, it is feasible to simulate a direct-injection engine using a detailed n-heptane mechanism with 543 species

  10. CAD/CAM/CAI Application for High-Precision Machining of Internal Combustion Engine Pistons

    Directory of Open Access Journals (Sweden)

    V. V. Postnov

    2014-07-01

    Full Text Available CAD/CAM/CAI application solutions for internal combustion engine pistons machining was analyzed. Low-volume technology of internal combustion engine pistons production was proposed. Fixture for CNC turning center was designed.

  11. Synthesis Gas from Pyrolysed Plastics for Combustion Engine

    Directory of Open Access Journals (Sweden)

    Chríbik Andrej

    2015-12-01

    Full Text Available The article discusses the application of synthesis gas from pyrolysis of plastics in petrol engine. The appropriate experimental measurements were performed on a combustion engine LGW 702 designated for micro-cogeneration unit. The power parameters, economic and internal parameters of the engine were compared to the engine running on the reference fuel - natural gas and synthesis gas. Burning synthesis gas leads to decreased performance by about 5% and to increased mass hourly consumption by 120%. In terms of burning, synthesis gas has similar properties as natural gas. More significant changes are observed in even burning of fuel in consecutive cycles.

  12. Air supply system for an internal combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Eftink, A.

    1992-06-11

    The present invention describes a system for supplying the primary combustion air to a reciprocating piston internal combustion engine including a trochoidal chamber air pump having a pair of pumping chambers interposed between an air intake and each of the cylinders of the engine. Each pumping chamber has an air inlet connected to an air intake, and an air outlet that is connected to the cylinders. In a two-cycle mode of operation, each pumping chamber outlet is connected to one engine cylinder. In a four-cycle mode of operation, each pumping chamber outlet is connected to a pair of cylinders to supply air during the intake stroke. The input shaft of the trochoidal chamber air pump is driven by, and may be connected to, the crankshaft of the engine so as to rate on a 1:1 ratio. (author)

  13. Challenges in simulation of chemical processes in combustion furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Hupa, M.; Kilpinen, P. [Aabo Akademi, Turku (Finland)

    1996-12-31

    The presentation gives an introduction to some of the present issues and problems in treating the complex chemical processes in combustion. The focus is in the coupling of the hydrocarbon combustion process with nitrogen oxide formation and destruction chemistry in practical furnaces or flames. Detailed kinetic modelling based on schemes of elementary reactions are shown to be a useful novel tool for identifying and studying the key reaction paths for nitrogen oxide formation and destruction in various systems. The great importance of the interaction between turbulent mixing and combustion chemistry is demonstrated by the sensitivity of both methane oxidation chemistry and fuel nitrogen conversion chemistry to the reactor and mixing pattern chosen for the kinetic calculations. The fluidized bed combustion (FBC) nitrogen chemistry involves several important heterogeneous reactions. Particularly the char in the bed plays an essential role. Recent research has advanced rapidly and the presentation proposes an overall picture of the fuel nitrogen reaction routes in circulating FBC conditions. (author)

  14. Combustion and Performance Characteristics of CI Engine Running with Biodiesel

    OpenAIRE

    Tesfa, Belachew; Mishra, Rakesh; Gu, Fengshou; Ball, Andrew

    2013-01-01

    Biodiesel is one of the alternative fuels which is renewable and environmentally friendly and can be used in diesel engines with little or no modifications. In the present study, experimental investigations were carried out on the effects of biodiesel types, biodiesel fraction and physical properties on the combustion and performance characteristics of a compression ignition (CI) engine. The experimental work was conducted on a four-cylinder, four -stroke, direct injection (DI) and turbocharg...

  15. A Simplified Model of the Internal Combustion Engine

    Directory of Open Access Journals (Sweden)

    Christofer Neff

    2013-01-01

    Full Text Available This project further investigates a model of a simplified internal combustion engine considered by Kranc in 1977. Using Euler’s method for ordinary differential equations, we modeled the interaction between the engine’s flywheel and thermodynamic power cycle. Approximating with sufficiently small time intervals (0.001 seconds over a period of 12 seconds reproduced Kranc’s results with the engine having an average angular velocity of 72/sec.

  16. The purification of internal combustion engine exhaust emissions

    Energy Technology Data Exchange (ETDEWEB)

    Davies, M.J.; Jorgensen, Norman; Carlow, J.S.; Raybone, David.

    1994-03-02

    In this patent, improved catalytic reduction of exhaust gas pollutants from internal combustion engines is described. During the warm-up phase of the cycle, a plasma discharge is initiated in the exhaust gases upstream of the catalytic converter. The plasma is controlled using sensors which detect the catalyst temperature and gas pressure and flow rate. (UK)

  17. High-Speed Visualisation of Combustion in Modern Gasoline Engines

    Science.gov (United States)

    Sauter, W.; Nauwerck, A.; Han, K.-M.; Pfeil, J.; Velji, A.; Spicher, U.

    2006-07-01

    Today research and development in the field of gasoline engines have to face a double challenge: on the one hand, fuel consumption has to be reduced, while on the other hand, ever more stringent emission standards have to be fulfilled. The development of engines with its complexity of in-cylinder processes requires modern development tools to exploit the full potential in order to reduce fuel consumption. Especially optical, non-intrusive measurement techniques will help to get a better understanding of the processes. With the presented high-speed visualisation system the electromagnetic radiation from combustion in the UV range is collected by an endoscope and transmitted to a visualisation system by 10, 000 optical fibres. The signal is projected to 1, 920 photomultipliers, which convert the optical into electric signals with a maximum temporal resolution of 200 kHz. This paper shows the systematic application of flame diagnostics in modern combustion systems. For this purpose, a single-cylinder SI engine has been modified for a spray guided combustion strategy as well as for HCCI. The characteristics of flame propagation in both combustion modes were recorded and correlated with thermodynamic analyses. In case of the spray guided GDI engine, high pressure fuel injection was applied and evaluated.

  18. COMBUSTION STAGE NUMERICAL ANALYSIS OF A MARINE ENGINE

    Directory of Open Access Journals (Sweden)

    DOREL DUMITRU VELCEA

    2016-06-01

    Full Text Available The primary goal of engine design is to maximize each efficiency factor, in order to extract the most power from the least amount of fuel. In terms of fluid dynamics, the volumetric and combustion efficiency are dependent on the fluid dynamics in the engine manifolds and cylinders. Cold flow analysis involves modeling the airflow in the transient engine cycle without reactions. The goal is to capture the mixture formation process by accurately accounting for the interaction of moving geometry with the fluid dynamics of the induction process. The changing characteristics of the air flow jet that tumbles into the cylinder with swirl via intake valves and the exhaust jet through the exhaust valves as they open and close can be determined, along with the turbulence production from swirl and tumble due to compression and squish. The target of this paper was to show how, by using the reverse engineering techniques, one may replicate and simulate the functioning conditions and parameters of an existing marine engine. The departing information were rather scarce in terms of real processes taking place in the combustion stage, but at the end we managed to have a full picture of the main parameters evolution during the combustion phase inside this existing marine engine

  19. Pocket wheel engine as an internal combustion engine. Taschenscheibenmotor als Verbrennungsmotor

    Energy Technology Data Exchange (ETDEWEB)

    Hellmuth, H.J.

    1990-09-27

    All spark ignition and diesel engines have large oscillating masses, a high frictional resistance and do not run vibration-free. Wankel engines effect only a partial combustion due to the unfavourable shape of the combustion chamber: the expansive force is converted into rotating movement via mechanical deflection. The new internal combustion engine is to have a low weight, require little space and run vibration-free with a high efficiency. The expansive force is to be converted directly into rotating movement. A screw compressor (3) suctions and compresses an air-fuel mixture. The combustion chamber is charged periodically with the compressed mixture via a slit side shaft (6). The slit side shaft (6) closes the combustion chamber (7) at the rear. The mixture is ignited. The flap (8) opens the combustion chamber (7) at the front and the exanding gas sets the pocket wheel connected to the main shaft (15) rotating. The compressor (3) and the slit side shaft (6) are driven directly by the main shaft (15). The pocket wheel engine can be employed in all fields where internal combustion engines have been used until now.

  20. Modelling of fuel spray and combustion in diesel engines

    Energy Technology Data Exchange (ETDEWEB)

    Huttunen, M.T.; Kaario, O.T. [VTT Energy, Espoo (Finland)

    1997-12-31

    Fuel spray and air motion characteristics and combustion in direct injection (DI) diesel engines was studied using computational models of the commercial CFD-code FIRE. Physical subprocesses modelled included Lagrangian spray droplet movement and behaviour (atomisation, evaporation and interaction of spray droplets) and combustion of evaporated liquid spray in the gas phase. Fuel vapour combustion rate was described by the model of Magnussen and Hjertager. The standard k,{epsilon}-model was used for turbulence. In order to be able to predict combustion accurately, the fuel spray penetration should be predicted with reasonable accuracy. In this study, the standard drag coefficient had to be reduced in order to match the computed penetration to the measured one. In addition, the constants in the submodel describing droplet breakup also needed to be adjusted for closer agreement with the measurements. The characteristic time scale of fuel consumption rate k/C{sub R} {epsilon} strongly influenced the heat release and in-cylinder pressure. With a value around 2.0 to 5.0 for C{sub R}, the computed in-cylinder pressure during the compression stroke agreed quite well with the measurements. On the other hand, the in-cylinder pressure was underpredicted during the expansion stroke. This is partly due to the fact that hydrocarbon fuel combustion was modelled as a one-step reaction reading to CO{sub 2} and H{sub 2}O and inadequate description of the mixing of reactants and combustion products. (author) 16 refs.

  1. Gasoline Engine HCCI Combustion - Extending the high load limit

    Energy Technology Data Exchange (ETDEWEB)

    Dahl, Daniel

    2012-07-01

    There is an increasing global focus on reducing emissions of greenhouse gases. For the automotive industry this means reducing CO2 emissions of the vehicles manufactured, which is synonymous with reducing their fuel consumption or adapting them for using renewable fuels. This thesis is based on a project aimed at improving the efficiency of gasoline engines in the lower load/speed region. The focus was mainly on a combustion strategy called homogeneous charge compression ignition (HCCI), but also on homogeneous lean and stratified lean spark-ignited combustion. In contrast to traditional stoichiometric spark-ignited combustion, HCCI can operate with diluted mixtures, which leads to better cycle efficiency, smaller pumping losses and smaller heat losses. However, at relatively high loads, HCCI combustion becomes excessively rapid, generating in-cylinder pressure oscillations (ringing), which are perceived as noise by the human ear. The main objective of the project was to identify ways to avoid this ringing behaviour in order to increase the upper load limit of HCCI. This is vital to avoid the need for mode switches to spark-ignited combustion at higher loads and to operate the engine as much as possible in the more effective HCCI mode. The strategy for reducing ringing investigated most extensively in the project was charge stratification, achieved by injecting part of the fuel late in the compression stroke. Available literature on effects of this strategy gave conflicting indications, both positive and negative effects have been reported, depending on the type of fuel and engine used. It was soon found that the strategy is effective for reducing ringing, but with resulting increases of NOX emissions. Further, in order for the strategy to be effective, global air/fuel ratios must not be much leaner than stoichiometric. The increases in NOX emissions were countered by shifting the ratio towards stoichiometric using exhaust gas recirculation (EGR), allowing a three

  2. Chemical Kinetic Study of Nitrogen Oxides Formation Trends in Biodiesel Combustion

    Directory of Open Access Journals (Sweden)

    Junfeng Yang

    2012-01-01

    Full Text Available The use of biodiesel in conventional diesel engines results in increased NOx emissions; this presents a barrier to the widespread use of biodiesel. The origins of this phenomenon were investigated using the chemical kinetics simulation tool: CHEMKIN-2 and the CFD KIVA3V code, which was modified to account for the physical properties of biodiesel and to incorporate semidetailed mechanisms for its combustion and the formation of emissions. Parametric ϕ-T maps and 3D engine simulations were used to assess the impact of using oxygen-containing fuels on the rate of NO formation. It was found that using oxygen-containing fuels allows more O2 molecules to present in the engine cylinder during the combustion of biodiesel, and this may be the cause of the observed increase in NO emissions.

  3. Sustainability in Chemical Engineering Curriculum

    Science.gov (United States)

    Glassey, Jarka; Haile, Sue

    2012-01-01

    Purpose: The purpose of this paper is to describe a concentrated strategy to embed sustainability teaching into a (chemical) engineering undergraduate curriculum throughout the whole programme. Innovative teaching approaches in subject-specific context are described and their efficiency investigated. Design/methodology/approach: The activities in…

  4. Reconstruction of an engine combustion process with a neural network

    Energy Technology Data Exchange (ETDEWEB)

    Jacob, P.J.; Gu, F.; Ball, A.D. [School of Engineering, University of Manchester, Manchester (United Kingdom)

    1997-12-31

    The cylinder pressure waveform in an internal combustion engine is one of the most important parameters in describing the engine combustion process. It is used for a range of diagnostic tasks such as identification of ignition faults or mechanical wear in the cylinders. However, it is very difficult to measure this parameter directly. Never-the-less, the cylinder pressure may be inferred from other more readily obtainable parameters. In this presentation it is shown how a Radial Basis Function network, which may be regarded as a form of neural network, may be used to model the cylinder pressure as a function of the instantaneous crankshaft velocity, recorded with a simple magnetic sensor. The application of the model is demonstrated on a four cylinder DI diesel engine with data from a wide range of speed and load settings. The prediction capabilities of the model once trained are validated against measured data. (orig.) 4 refs.

  5. Introduction to Analytical Methods for Internal Combustion Engine Cam Mechanisms

    CERN Document Server

    Williams, J J

    2013-01-01

    Modern design methods of Automotive Cam Design require the computation of a range of parameters. This book provides a logical sequence of steps for the derivation of the relevant equations from first principles, for the more widely used cam mechanisms. Although originally derived for use in high performance engines, this work is equally applicable to the design of mass produced automotive and other internal combustion engines.   Introduction to Analytical Methods for Internal Combustion Engine Cam Mechanisms provides the equations necessary for the design of cam lift curves with an associated smooth acceleration curve. The equations are derived for the kinematics and kinetics of all the mechanisms considered, together with those for cam curvature and oil entrainment velocity. This permits the cam shape, all loads, and contact stresses to be evaluated, and the relevant tribology to be assessed. The effects of asymmetry on the manufacture of cams for finger follower and offset translating curved followers is ...

  6. Comparison of an Internal Combustion Engine Derating Operated on Producer Gas from Coal and Biomass Gasification

    Directory of Open Access Journals (Sweden)

    Muhammad Ade Andriansyah Efendi

    2016-06-01

    Full Text Available Gasification is an effective and clean way to convert coal and biomass into useful fuels and chemical feedstocks. Producer gas utilization for internal combustion engine has been studied, not only from biomass gasification but also from coal gasification. This paper compares the research that has done author using coal gasification with other research results using biomass gasification. Coal gasifier performance test conducted with capacity of 20 kg/h coal. The proximate and ultimate analysis of raw coal, ash product and producer gas was conducted and comparised. The result of analysis shows that the efficiency of the coal gasification was 61% while range of gasifier efficiency for biomass is between 50-80%. Meanwhile, the experimental results on the performance of internal combustion engines using gas producer shows that the derating for power generation using coal producer gas was 46% and biomass was 20-50% depend on compression ratio of engine and characteristic of producer gas. 

  7. Multi-dimensional Modeling of the Application of Catalytic Combustion to Homogeneous Charge Compression Ignition Engine

    Institute of Scientific and Technical Information of China (English)

    Wen Zeng; MaoZhao Xie

    2006-01-01

    The detailed surface reaction mechanism of methane on rhodium catalyst was analyzed.Comparisons between numerical simulation and experiments showed a basic agreement.The combustion process of homogeneous charge compression ignition (HCCI) engine whose piston surface has been coated with catalyst (rhodium and platinum) was numerically investigated.A multi-dimensional model with detailed chemical kinetics was built.The effects of catalytic combustion on the ignition timing,the temperature and CO concentration fields,and HC,CO and NOx emissions of the HCCI engine were discussed.The results showed the ignition timing of the HCCI engine was advanced and the emissions of HC and CO were decreased by the catalysis.

  8. Chemical kinetics and combustion modelling with CFX 4

    Energy Technology Data Exchange (ETDEWEB)

    Stopford, P. [AEA Technology, Computational Fluid Dynamics Services Harwell, Oxfordshire (United Kingdom)

    1997-12-31

    The presentation describes some recent developments in combustion and kinetics models used in the CFX software of AEA Technology. Three topics are highlighted: the development of coupled solvers in a traditional `SIMPLE`-based CFD code, the use of detailed chemical kinetics mechanism via `look-up` tables and the application of CFD to large-scale multi-burner combustion plant. The aim is identify those physical approximations and numerical methods that are likely to be most useful in the future and those areas where further developments are required. (author) 6 refs.

  9. Chemical kinetic simulation of kerosene combustion in an individual flame tube

    Directory of Open Access Journals (Sweden)

    Wen Zeng

    2014-05-01

    Full Text Available The use of detailed chemical reaction mechanisms of kerosene is still very limited in analyzing the combustion process in the combustion chamber of the aircraft engine. In this work, a new reduced chemical kinetic mechanism for fuel n-decane, which selected as a surrogate fuel for kerosene, containing 210 elemental reactions (including 92 reversible reactions and 26 irreversible reactions and 50 species was developed, and the ignition and combustion characteristics of this fuel in both shock tube and flat-flame burner were kinetic simulated using this reduced reaction mechanism. Moreover, the computed results were validated by experimental data. The calculated values of ignition delay times at pressures of 12, 50 bar and equivalence ratio is 1.0, 2.0, respectively, and the main reactants and main products mole fractions using this reduced reaction mechanism agree well with experimental data. The combustion processes in the individual flame tube of a heavy duty gas turbine combustor were simulated by coupling this reduced reaction mechanism of surrogate fuel n-decane and one step reaction mechanism of surrogate fuel C12H23 into the computational fluid dynamics software. It was found that this reduced reaction mechanism is shown clear advantages in simulating the ignition and combustion processes in the individual flame tube over the one step reaction mechanism.

  10. Chemical looping combustion of coal in interconnected fluidized beds

    Institute of Scientific and Technical Information of China (English)

    SHEN LaiHong; ZHENG Min; XIAO Jun; ZHANG Hui; XIAO Rui

    2007-01-01

    Chemical looping combustion is the indirect combustion by use of oxygen carrier.It can be used for CO2 capture in power generating processes. In this paper,chemical looping combustion of coal in interconnected fluidized beds with inherent separation of CO2 is proposed. It consists of a high velocity fluidized bed as an air reactor in which oxygen carrier is oxidized, a cyclone, and a bubbling fluidized bed as a fuel reactor in which oxygen carrier is reduced by direct and indirect reactions with coal. The air reactor is connected to the fuel reactor through the cyclone. To raise the high carbon conversion efficiency and separate oxygen carrier particle from ash, coal slurry instead of coal particle is introduced into the bottom of the bubbling fluidized bed. Coal gasification and the reduction of oxygen carrier with the water gas take place simultaneously in the fuel reactor. The flue gas from the fuel reactor is CO2 and water. Almost pure CO2 could be obtained after the condensation of water. The reduced oxygen carrier is then returned back to the air reactor, where it is oxidized with air. Thermodyanmics analysis indicates that NiO/Ni oxygen carrier is the optimal one for chemical looping combustion of coal.Simulation of the processes for chemical looping combustion of coal, including coal gasification and reduction of oxygen carrier, is carried out with Aspen Plus software. The effects of air reactor temperature, fuel reactor temperature, and ratio of water to coal on the composition of fuel gas, recirculation of oxygen carrier particles, etc., are discussed. Some useful results are achieved. The suitable temperature of air reactor should be between 1050-1150Cand the optimal temperature of the fuel reactor be between 900-950℃.

  11. Chemical looping combustion of coal in interconnected fluidized beds

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Chemical looping combustion is the indirect combustion by use of oxygen carrier. It can be used for CO2 capture in power generating processes. In this paper, chemical looping combustion of coal in interconnected fluidized beds with inherent separation of CO2 is proposed. It consists of a high velocity fluidized bed as an air reactor in which oxygen carrier is oxidized, a cyclone, and a bubbling fluidized bed as a fuel reactor in which oxygen carrier is reduced by direct and indirect reactions with coal. The air reactor is connected to the fuel reactor through the cyclone. To raise the high carbon conversion efficiency and separate oxygen carrier particle from ash, coal slurry instead of coal particle is introduced into the bottom of the bubbling fluidized bed. Coal gasification and the reduction of oxygen carrier with the water gas take place simultaneously in the fuel reactor. The flue gas from the fuel reactor is CO2 and water. Almost pure CO2 could be obtained after the con- densation of water. The reduced oxygen carrier is then returned back to the air reactor, where it is oxidized with air. Thermodyanmics analysis indicates that NiO/Ni oxygen carrier is the optimal one for chemical looping combustion of coal. Simulation of the processes for chemical looping combustion of coal, including coal gasification and reduction of oxygen carrier, is carried out with Aspen Plus software. The effects of air reactor temperature, fuel reactor temperature, and ratio of water to coal on the composition of fuel gas, recirculation of oxygen carrier par- ticles, etc., are discussed. Some useful results are achieved. The suitable tem- perature of air reactor should be between 1050―1150℃and the optimal temperature of the fuel reactor be between 900―950℃.

  12. Effects of compression ratio on the combustion characteristics of a homogeneous charge compression ignition engine

    Institute of Scientific and Technical Information of China (English)

    SONG Ruizhi; HU Tiegang; ZHOU Longbao; LIU Shenghua; LI Wei

    2007-01-01

    The effects of homogeneous charge compression ignition (HCCI) engine compression ratio on its combustion characteristics were studied experimentally on a modified TY1100 single cylinder engine fueled with dimethyl ether.The results show that dimethyl ether (DME) HCCI engine can work stably and can realize zero nitrogen oxides (NOx)emission and smokeless combustion under the compression ratio of both 10.7 and 14.The combustion process has obvious two stage combustion characteristics at ε = 10.7(εrefers to compression ratio),and the combustion beginning point is decided by the compression temperature,which varies very little with the engine load;the combustion beginning point is closely related to the engine load (concentration of mixture) with the increase in the compression temperature,and it moves forward versus crank angle with the increase in the engine load at ε = 14;the combustion durations are shortened with the increase in the engine load under both compression ratios.

  13. High Temperature Chemical Kinetic Combustion Modeling of Lightly Methylated Alkanes

    Energy Technology Data Exchange (ETDEWEB)

    Sarathy, S M; Westbrook, C K; Pitz, W J; Mehl, M

    2011-03-01

    Conventional petroleum jet and diesel fuels, as well as alternative Fischer-Tropsch (FT) fuels and hydrotreated renewable jet (HRJ) fuels, contain high molecular weight lightly branched alkanes (i.e., methylalkanes) and straight chain alkanes (n-alkanes). Improving the combustion of these fuels in practical applications requires a fundamental understanding of large hydrocarbon combustion chemistry. This research project presents a detailed high temperature chemical kinetic mechanism for n-octane and three lightly branched isomers octane (i.e., 2-methylheptane, 3-methylheptane, and 2,5-dimethylhexane). The model is validated against experimental data from a variety of fundamental combustion devices. This new model is used to show how the location and number of methyl branches affects fuel reactivity including laminar flame speed and species formation.

  14. Method of fabricating a rocket engine combustion chamber

    Science.gov (United States)

    Holmes, Richard R. (Inventor); Mckechnie, Timothy N. (Inventor); Power, Christopher A. (Inventor); Daniel, Ronald L., Jr. (Inventor); Saxelby, Robert M. (Inventor)

    1993-01-01

    A process for making a combustion chamber for a rocket engine wherein a copper alloy in particle form is injected into a stream of heated carrier gas in plasma form which is then projected onto the inner surface of a hollow metal jacket having the configuration of a rocket engine combustion chamber is described. The particles are in the plasma stream for a sufficient length of time to heat the particles to a temperature such that the particles will flatten and adhere to previously deposited particles but will not spatter or vaporize. After a layer is formed, cooling channels are cut in the layer, then the channels are filled with a temporary filler and another layer of particles is deposited.

  15. Evaluation of the Migrating Combustion Chamber (MCC) engine

    Science.gov (United States)

    Miller, K. M.; Morar, Dorin

    1993-01-01

    The Belvoir Research, Development and Engineering Center (BRDEC) tested three Migrating Combustion Chamber (MCC) engines built by Engine Research Associates (ERA) for Natick RD and E Center. The MCC concept attempts to provide a lightweight, quiet engine having a cool exhaust gas stream. The cool exhaust is attained by capturing additional energy from expansion beyond that achievable in conventional engines by the use of gas porting to multiple expansion chambers; this provides a more efficient engine operation than is otherwise attainable for the configuration. The testing included determining the engine torque-speed-power characteristics and the Brake Specific Fuel Consumption (BSFC) under a variety of load conditions. Startability and operability were concerns; starting under normal ambient conditions was difficult. All testing was performed using a 10:1 fuel/oil mixture of low lead gasoline with AMZOIL synthetic lubricating oil for two-stroke engines. The maximum power achieved was 0.25 horsepower at 4,400 rpm. The peak torque observed was 69 oz.-in. at 3,200 rpm. It was not possible to make noise and vibration measurements during the testing cycle, but they appeared to be low. The MCC engines tested had relatively short lives, operating for less than 25 hours. Performance and durability improvements are necessary before this MCC design can be considered as a viable alternative to commercially available two-cycle engines.

  16. EXPERIMENTAL INVESTIGATION OF COMBUSTION, PERFORMANCE AND EMISSION CHARACTERISTICS OF DI DIESEL ENGINE UNDER HCCI MODE WITH POROUS MEDIUM COMBUSTION

    OpenAIRE

    Kannan, C.; P TAMILPORAI

    2010-01-01

    In recent times, homogeneous combustion has been a proven technology to attain high efficient and low emission engines. Homogenous Charge Compression Ignition (HCCI) engines are able to have efficiencies as high as Compression Ignition, Direct Injection (CIDI) engines, while producing ultra-low emissions of nitrogen oxides (NOx) and particulate matter (PM).HCCI combustion is achieved by controlling the temperature, pressure and composition of the fuel-air mixture so that it spontaneously gets...

  17. Enhanced efficiency of internal combustion engines by employing spinning gas

    Science.gov (United States)

    Geyko, V. I.; Fisch, N. J.

    2014-08-01

    The efficiency of the internal combustion engine might be enhanced by employing spinning gas. A gas spinning at near sonic velocities has an effectively higher heat capacity, which allows practical fuel cycles, which are far from the Carnot efficiency, to approach more closely the Carnot efficiency. A remarkable gain in fuel efficiency is shown to be theoretically possible for the Otto and Diesel cycles. The use of a flywheel, in principle, could produce even greater increases in efficiency.

  18. Enhanced efficiency of internal combustion engines by employing spinning gas.

    Science.gov (United States)

    Geyko, V I; Fisch, N J

    2014-08-01

    The efficiency of the internal combustion engine might be enhanced by employing spinning gas. A gas spinning at near sonic velocities has an effectively higher heat capacity, which allows practical fuel cycles, which are far from the Carnot efficiency, to approach more closely the Carnot efficiency. A remarkable gain in fuel efficiency is shown to be theoretically possible for the Otto and Diesel cycles. The use of a flywheel, in principle, could produce even greater increases in efficiency.

  19. Monitoring advances in chemical engineering

    OpenAIRE

    Peters, H.P.F.; Hartmann, D; Van Raan, A.F.J.

    1988-01-01

    This paper describes an approach to monitoring scientific progress in chemical engineering in order to operationalize concepts such as 'research performance' which can be used in the retrospective evaluation and the future anticipation of scientific research activities. We focus on various quantitative methods. Bibliometric methods form an important, but not the only, part of the work. The use of bibliometric approaches and measures is plagued by many problems. This is es...

  20. Chemical engineering of molecular qubits.

    Science.gov (United States)

    Wedge, C J; Timco, G A; Spielberg, E T; George, R E; Tuna, F; Rigby, S; McInnes, E J L; Winpenny, R E P; Blundell, S J; Ardavan, A

    2012-03-09

    We show that the electron spin phase memory time, the most important property of a molecular nanomagnet from the perspective of quantum information processing, can be improved dramatically by chemically engineering the molecular structure to optimize the environment of the spin. We vary systematically each structural component of the class of antiferromagnetic Cr(7)Ni rings to identify the sources of decoherence. The optimal structure exhibits a phase memory time exceeding 15  μs.

  1. Combustion quasi-two zone predictive model for dual fuel engines

    Energy Technology Data Exchange (ETDEWEB)

    Abd Alla, G.H.; Soliman, H.A.; Badr, O.A.; Abd Rabbo, M.F. [Department of Mechanical Engineering, Shoubra Faculty of Engineering, Zagazig University, 108, Shoubra Street, Cairo (Egypt)

    2001-08-01

    A quasi-two zone predictive model is developed in the present work for prediction of the combustion processes in dual fuel engines and some of their performance features. Methane is used as the main fuel while employing a small quantity of liquid fuel (pilot) injected through the conventional Diesel fuel system. This model emphasizes the effects of chemical kinetics activity of the premixed gaseous fuel on the combustion performance, while the role of the pilot fuel in the ignition and heat release processes is considered. A detailed chemical kinetic scheme consists of 178 elementary reaction steps, and 41 chemical species are employed to describe the oxidation of the gaseous fuel from the start of compression to the end of the expansion process. The associated formation and concentrations of exhaust emissions are correspondingly established. This combustion model is able to establish the development of the combustion process with time and the associated important operating parameters, such as pressure, temperature, rates of energy release and composition. Predicted values for methane operation show good agreement with corresponding previous experimental values over a range of operating conditions mainly associated with high load operation. (Author)

  2. Chemical Engineering Students: A Distinct Group among Engineers

    Science.gov (United States)

    Godwin, Allison; Potvin, Geoff

    2013-01-01

    This paper explores differences between chemical engineering students and students of other engineering disciplines, as identified by their intended college major. The data used in this analysis was taken from the nationally representative Sustainability and Gender in Engineering (SaGE) survey. Chemical engineering students differ significantly…

  3. A New Paradigm for Chemical Engineering?

    DEFF Research Database (Denmark)

    Gani, Rafiqul

    businesses has been observed. There is an increasing trend within the chemical industry to focus on products and the sustainable processes that can make them. Do these changes point to a paradigm shift in chemical engineering as a discipline? Historically, two previous paradigm shifts in chemical engineering...... corresponded to major shifts in chemical engineering as a discipline, which affected not only the education of chemical engineers, but also the development of chemical engineering as a discipline. Has the time come for a new paradigm shift that will prepare the current and future chemical engineering graduates...... to tackle the complex problems facing the chemicals based industries and serve the modern society more efficiently? The lecture will review the current status of chemical engineering as a discipline, the proposals for the third paradigm, the need for such a paradigm shift and related educational issues....

  4. Elimination of abnormal combustion in a hydrogen-fueled engine

    Energy Technology Data Exchange (ETDEWEB)

    Swain, M.R.; Swain, M.N. [Analytical Technologies, Inc., Miami, FL (United States)

    1995-11-01

    This report covers the design, construction, and testing of a dedicated hydrogen-fueled engine. Both part-load and full-load data were taken under laboratory conditions. The engine design included a billet aluminum single combustion chamber cylinder-head with one intake valve, two sodium coiled exhaust valves, and two spark plugs. The cylinder-head design also included drilled cooling passages. The fuel-delivery system employed two modified Siemens electrically actuated fuel injectors, The exhaust system included two separate headers, one for each exhaust port. The piston/ring combination was designed specifically for hydrogen operation.

  5. Influence of intake air temperature on internal combustion engine operation

    Science.gov (United States)

    Birtok-Băneasă, C.; Raţiu, S.; Hepuţ, T.

    2017-01-01

    This paper presents three methods for reduce thermal losses in the intake system with improvement of airflow and thermal protection. In the experiment are involved two patented devices conceived by the author and one PhD theme device: 1- Dynamic device for air transfer, 2-Integrated thermal deflector, and, 3-Advanced thermal protection. The tests were carried on different vehicle running in real traffic and in the Internal Combustion Engines Laboratory, within the specialization “Road vehicle” belonging to the Faculty of Engineering Hunedoara, component of Politehnica University of Timişoara. The results have been processed and compared whit the ones obtained without these devices.

  6. Research Needs and Impacts in Predictive Simulation for Internal Combustion Engines (PreSICE)

    Energy Technology Data Exchange (ETDEWEB)

    Eckerle, Wayne [Cummins, Inc., Columbus, IN (United States); Rutland, Chris [Univ. of Wisconsin, Madison, WI (United States); Rohlfing, Eric [Dept. of Energy (DOE), Washington DC (United States). Office of Science; Singh, Gurpreet [Dept. of Energy (DOE), Washington DC (United States). Office of Energy Efficiency and Renewable Energy; McIlroy, Andrew [Sandia National Lab. (SNL-CA), Livermore, CA (United States)

    2011-03-03

    outcome will be: New and deeper understanding of the relevant fundamental physical and chemical processes in advanced combustion technologies, Implementation of this understanding into models and simulation tools appropriate for both exploration and design, and Sufficient validation with uncertainty quantification to provide confidence in the simulation results. These outcomes will provide the design tools for industry to reduce development time by up to 30% and improve engine efficiencies by 30% to 50%. The improved efficiencies applied to the national mix of transportation applications have the potential to save over 5 million barrels of oil per day, a current cost savings of $500 million per day.

  7. Flexible fuel engine based on multi-combustion control technologies

    Institute of Scientific and Technical Information of China (English)

    LI Xiaolu; HUANG Zhen; QIAO Xinqi; SONG Jun; FANG Junhua; XIA Huimin

    2005-01-01

    A combustion control strategy is proposed for diesel engine to reduce PM and NOx emissions significantly, which adopts some technologies including internal exhaust gas recirculation (EGR), split spray, adjustable fuel delivery advance angle and the application of alternative fuels. Based on this strategy, a flexible fuel engine has been developed. The experimental results show that this engine can be fueled with diesel fuel, alcohol, dimethyl carbonate (DMC), etc. It works with extremely low levels of particulate matter (PM) and NOx, 2~3% higher effective thermal efficiency on moderate and high loads when alternative fuels are used. This engine not only has lower exhaust emissions, but also can be fueled with those alternative fuels, which are difficult to be ignited by compression.

  8. Combustion chemical vapor desposited coatings for thermal barrier coating systems

    Energy Technology Data Exchange (ETDEWEB)

    Hampikian, J.M.; Carter, W.B. [Georgia Institute of Technology, Atlanta, GA (United States)

    1995-10-01

    The new deposition process, combustion chemical vapor deposition, shows a great deal of promise in the area of thermal barrier coating systems. This technique produces dense, adherent coatings, and does not require a reaction chamber. Coatings can therefore be applied in the open atmosphere. The process is potentially suitable for producing high quality CVD coatings for use as interlayers between the bond coat and thermal barrier coating, and/or as overlayers, on top of thermal barrier coatings.

  9. Dynamic estimator for determining operating conditions in an internal combustion engine

    Science.gov (United States)

    Hellstrom, Erik; Stefanopoulou, Anna; Jiang, Li; Larimore, Jacob

    2016-01-05

    Methods and systems are provided for estimating engine performance information for a combustion cycle of an internal combustion engine. Estimated performance information for a previous combustion cycle is retrieved from memory. The estimated performance information includes an estimated value of at least one engine performance variable. Actuator settings applied to engine actuators are also received. The performance information for the current combustion cycle is then estimated based, at least in part, on the estimated performance information for the previous combustion cycle and the actuator settings applied during the previous combustion cycle. The estimated performance information for the current combustion cycle is then stored to the memory to be used in estimating performance information for a subsequent combustion cycle.

  10. Nitrogen enriched combustion of a natural gas internal combustion engine to reduce NO.sub.x emissions

    Science.gov (United States)

    Biruduganti, Munidhar S.; Gupta, Sreenath Borra; Sekar, R. Raj; McConnell, Steven S.

    2008-11-25

    A method and system for reducing nitrous oxide emissions from an internal combustion engine. An input gas stream of natural gas includes a nitrogen gas enrichment which reduces nitrous oxide emissions. In addition ignition timing for gas combustion is advanced to improve FCE while maintaining lower nitrous oxide emissions.

  11. Virtual Instrument for Emissions Measurement of Internal Combustion Engines

    Directory of Open Access Journals (Sweden)

    Armando Pérez

    2016-01-01

    Full Text Available The gases emissions measurement systems in internal combustion engines are strict and expensive nowadays. For this reason, a virtual instrument was developed to measure the combustion emissions from an internal combustion diesel engine, running with diesel-biodiesel mixtures. This software is called virtual instrument for emissions measurement (VIEM, and it was developed in the platform of LabVIEW 2010® virtual programming. VIEM works with sensors connected to a signal conditioning system, and a data acquisition system is used as interface for a computer in order to measure and monitor in real time the emissions of O2, NO, CO, SO2, and CO2 gases. This paper shows the results of the VIEM programming, the integrated circuits diagrams used for the signal conditioning of sensors, and the sensors characterization of O2, NO, CO, SO2, and CO2. VIEM is a low-cost instrument and is simple and easy to use. Besides, it is scalable, making it flexible and defined by the user.

  12. Virtual Instrument for Emissions Measurement of Internal Combustion Engines

    Science.gov (United States)

    Pérez, Armando; Montero, Gisela; Coronado, Marcos; García, Conrado; Pérez, Rubén

    2016-01-01

    The gases emissions measurement systems in internal combustion engines are strict and expensive nowadays. For this reason, a virtual instrument was developed to measure the combustion emissions from an internal combustion diesel engine, running with diesel-biodiesel mixtures. This software is called virtual instrument for emissions measurement (VIEM), and it was developed in the platform of LabVIEW 2010® virtual programming. VIEM works with sensors connected to a signal conditioning system, and a data acquisition system is used as interface for a computer in order to measure and monitor in real time the emissions of O2, NO, CO, SO2, and CO2 gases. This paper shows the results of the VIEM programming, the integrated circuits diagrams used for the signal conditioning of sensors, and the sensors characterization of O2, NO, CO, SO2, and CO2. VIEM is a low-cost instrument and is simple and easy to use. Besides, it is scalable, making it flexible and defined by the user. PMID:27034893

  13. Natural Ores as Oxygen Carriers in Chemical Looping Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Hanjing; Siriwardane, Ranjani; Simonyi, Thomas; Poston, James

    2013-08-01

    Chemical looping combustion (CLC) is a combustion technology that utilizes oxygen from oxygen carriers (OC), such as metal oxides, instead of air to combust fuels. The use of natural minerals as oxygen carriers has advantages, such as lower cost and availability. Eight materials, based on copper or iron oxides, were selected for screening tests of CLC processes using coal and methane as fuels. Thermogravimetric experiments and bench-scale fixed-bed reactor tests were conducted to investigate the oxygen transfer capacity, reaction kinetics, and stability during cyclic reduction/oxidation reaction. Most natural minerals showed lower combustion capacity than pure CuO/Fe{sub 2}O{sub 3} due to low-concentrations of active oxide species in minerals. In coal CLC, chryscolla (Cu-based), magnetite, and limonite (Fe-based) demonstrated better reaction performances than other materials. The addition of steam improved the coal CLC performance when using natural ores because of the steam gasification of coal and the subsequent reaction of gaseous fuels with active oxide species in the natural ores. In methane CLC, chryscolla, hematite, and limonite demonstrated excellent reactivity and stability in 50-cycle thermogravimetric analysis tests. Fe{sub 2}O{sub 3}-based ores possess greater oxygen utilization but require an activation period before achieving full performance in methane CLC. Particle agglomeration issues associated with the application of natural ores in CLC processes were also studied by scanning electron microscopy (SEM).

  14. Optimal control for chemical engineers

    CERN Document Server

    Upreti, Simant Ranjan

    2013-01-01

    Optimal Control for Chemical Engineers gives a detailed treatment of optimal control theory that enables readers to formulate and solve optimal control problems. With a strong emphasis on problem solving, the book provides all the necessary mathematical analyses and derivations of important results, including multiplier theorems and Pontryagin's principle.The text begins by introducing various examples of optimal control, such as batch distillation and chemotherapy, and the basic concepts of optimal control, including functionals and differentials. It then analyzes the notion of optimality, de

  15. Engine modeling and control modeling and electronic management of internal combustion engines

    CERN Document Server

    Isermann, Rolf

    2014-01-01

    The increasing demands for internal combustion engines with regard to fuel consumption, emissions and driveability lead to more actuators, sensors and complex control functions. A systematic implementation of the electronic control systems requires mathematical models from basic design through simulation to calibration. The book treats physically-based as well as models based experimentally on test benches for gasoline (spark ignition) and diesel (compression ignition) engines and uses them for the design of the different control functions. The main topics are: - Development steps for engine control - Stationary and dynamic experimental modeling - Physical models of intake, combustion, mechanical system, turbocharger, exhaust, cooling, lubrication, drive train - Engine control structures, hardware, software, actuators, sensors, fuel supply, injection system, camshaft - Engine control methods, static and dynamic feedforward and feedback control, calibration and optimization, HiL, RCP, control software developm...

  16. Physical and chemical effects of low octane gasoline fuels on compression ignition combustion

    KAUST Repository

    Badra, Jihad

    2016-09-30

    Gasoline compression ignition (GCI) engines running on low octane gasoline fuels are considered an attractive alternative to traditional spark ignition engines. In this study, three fuels with different chemical and physical characteristics have been investigated in single cylinder engine running in GCI combustion mode at part-load conditions both experimentally and numerically. The studied fuels are: Saudi Aramco light naphtha (SALN) (Research octane number (RON) = 62 and final boiling point (FBP) = 91 °C), Haltermann straight run naphtha (HSRN) (RON = 60 and FBP = 140 °C) and a primary reference fuel (PRF65) (RON = 65 and FBP = 99 °C). Injection sweeps, where the start of injection (SOI) is changed between −60 and −11 CAD aTDC, have been performed for the three fuels. Full cycle computational fluid dynamics (CFD) simulations were executed using PRFs as chemical surrogates for the naphtha fuels. Physical surrogates based on the evaporation characteristics of the naphtha streams have been developed and their properties have been implemented in the engine simulations. It was found that the three fuels have similar combustion phasings and emissions at the conditions tested in this work with minor differences at SOI earlier than −30 CAD aTDC. These trends were successfully reproduced by the CFD calculations. The chemical and physical effects were further investigated numerically. It was found that the physical characteristics of the fuel significantly affect the combustion for injections earlier than −30 CAD aTDC because of the low evaporation rates of the fuel because of the higher boiling temperature of the fuel and the colder in-cylinder air during injection. © 2016 Elsevier Ltd

  17. Mixer for internal combustion engines. Gemischbildner fuer Brennkraftmaschinen

    Energy Technology Data Exchange (ETDEWEB)

    Haertel, G.; Schiele, W.; Schuerfeld, A.; Bianchi, V.; Abidin, A.

    1981-06-11

    The invention concerns a mixer for internal combustion engines with a pipe wall limiting the main flow path and heated for part of its length and with a throttle upstream and a fuel allocation device in the upstream part of a mixing chamber inside the pipe wall. The invention is characterised by the fact that the pipe wall surrounding the mixing chamber is made as a heating wall from the fuel allocation device to the throttle and the fuel allocation device guides the fuel to the heating wall. The heating wall is made as a double wall of a heat exchanger to guide the liquid or gaseous heating medium, such as engine cooling water or engine exhaust gas. The heating wall consists of an electrical resistance heating material on the inside. Other measures of the invention are described by system drawings and 33 patent claims.

  18. Internal combustion engines a detailed introduction to the thermodynamics of spark and compression ignition engines, their design and development

    CERN Document Server

    Benson, Rowland S

    1979-01-01

    Internal Combustion of Engines: A Detailed Introduction to the Thermodynamics of Spark and Compression Ignition Engines, Their Design and Development focuses on the design, development, and operations of spark and compression ignition engines. The book first describes internal combustion engines, including rotary, compression, and indirect or spark ignition engines. The publication then discusses basic thermodynamics and gas dynamics. Topics include first and second laws of thermodynamics; internal energy and enthalpy diagrams; gas mixtures and homocentric flow; and state equation. The text ta

  19. Hydrogen-Assisted IC Engine Combustion as a Route to Hydrogen Implementation

    Energy Technology Data Exchange (ETDEWEB)

    Andre Boehman; Daniel Haworth

    2008-09-30

    composition and utilization through laboratory studies of spark-ignition engine operation on H{sub 2}-NG and numerical simulation of the impact of hydrogen blending on the physical and chemical processes within the engine; and (2) Examination of hydrogen-assisted combustion in advanced compression-ignition engine processes. To that end, numerical capabilities were applied to the study of hydrogen assisted combustion and experimental facilities were developed to achieve the project objectives.

  20. 3-DIMENSIONAL Numerical Modeling on the Combustion and Emission Characteristics of Biodiesel in Diesel Engines

    Science.gov (United States)

    Yang, Wenming; An, Hui; Amin, Maghbouli; Li, Jing

    2014-11-01

    A 3-dimensional computational fluid dynamics modeling is conducted on a direct injection diesel engine fueled by biodiesel using multi-dimensional software KIVA4 coupled with CHEMKIN. To accurately predict the oxidation of saturated and unsaturated agents of the biodiesel fuel, a multicomponent advanced combustion model consisting of 69 species and 204 reactions combined with detailed oxidation pathways of methyl decenoate (C11H22O2), methyl-9-decenoate (C11H20O2) and n-heptane (C7H16) is employed in this work. In order to better represent the real fuel properties, the detailed chemical and thermo-physical properties of biodiesel such as vapor pressure, latent heat of vaporization, liquid viscosity and surface tension were calculated and compiled into the KIVA4 fuel library. The nitrogen monoxide (NO) and carbon monoxide (CO) formation mechanisms were also embedded. After validating the numerical simulation model by comparing the in-cylinder pressure and heat release rate curves with experimental results, further studies have been carried out to investigate the effect of combustion chamber design on flow field, subsequently on the combustion process and performance of diesel engine fueled by biodiesel. Research has also been done to investigate the impact of fuel injector location on the performance and emissions formation of diesel engine.

  1. Advancements in Development of Chemical-Looping Combustion: A Review

    Directory of Open Access Journals (Sweden)

    He Fang

    2009-01-01

    Full Text Available Chemical-looping combustion (CLC is a novel combustion technology with inherent separation of greenhouse CO2. Extensive research has been performed on CLC in the last decade with respect to oxygen carrier development, reaction kinetics, reactor design, system efficiencies, and prototype testing. Transition metal oxides, such as Ni, Fe, Cu, and Mn oxides, were reported as reactive species in the oxygen carrier particles. Ni-based oxygen carriers exhibited the best reactivity and stability during multiredox cycles. The performance of the oxygen carriers can be improved by changing preparation method or by making mixedoxides. The CLC has been demonstrated successfully in continuously operated prototype reactors based on interconnected fluidized-bed system in the size range of 0.3–50 kW. High fuel conversion rates and almost 100%  CO2 capture efficiencies were obtained. The CLC system with two interconnected fluidized-bed reactors was considered the most suitable reactor design. Development of oxygen carriers with excellent reactivity and stability is still one of the challenges for CLC in the near future. Experiences of building and operating the large-scale CLC systems are needed before this technology is used commercially. Chemical-looping reforming (CLR and chemical-looping hydrogen (CLH are novel chemical-looping techniques to produce synthesis gas and hydrogen deserving more attention and research.

  2. Numerical investigation of combustion field of hypervelocity scramjet engine

    Science.gov (United States)

    Zhang, Shikong; Li, Jiang; Qin, Fei; Huang, Zhiwei; Xue, Rui

    2016-12-01

    A numerical study of the ground testing of a hydrogen-fueled scramjet engine was undertaken using the commercial computational-fluid-dynamics code CFD++. The simulated Mach number was 12. A 7-species, 9-reaction-step hydrogen-air chemistry kinetics system was adopted for the Reynolds-averaged Navier-Stokes simulation. The two-equation SST turbulence model, which takes into account the wall functions, was used to handle the turbulence-chemistry interactions. The results were validated by experimentally measuring the wall pressure distribution, and the values obtained proved to be in good agreement. The flow pattern at non-reaction/reaction is presented, as are the results of analyzing the supersonic premix/non-premix flame structure, the reaction heat release distribution in different modes, and the change in the equivalence ratio. In this study, we realize the working mode of a hypervelocity engine and provide some suggestions for the combustion organization of the engine as well as offer insight into the potential for exploiting the processes of combustion and flow.

  3. A multipurpose reduced chemical-kinetic mechanism for methanol combustion

    Science.gov (United States)

    Fernández-Tarrazo, Eduardo; Sánchez-Sanz, Mario; Sánchez, Antonio L.; Williams, Forman A.

    2016-07-01

    A multipurpose reduced chemical-kinetic mechanism for methanol combustion comprising 8 overall reactions and 11 reacting chemical species is presented. The development starts by investigating the minimum set of elementary reactions needed to describe methanol combustion with reasonable accuracy over a range of conditions of temperature, pressure, and composition of interest in combustion. Starting from a 27-step mechanism that has been previously tested and found to give accurate predictions of ignition processes for these conditions, it is determined that the addition of 11 elementary reactions taken from its basis (San Diego) mechanism extends the validity of the description to premixed-flame propagation, strain-induced extinction of non-premixed flames, and equilibrium composition and temperatures, giving results that compare favourably with experimental measurements and also with computations using the 247-step detailed San Diego mechanism involving 50 reactive species. Specifically, premixed-flame propagation velocities and extinction strain rates for non-premixed counterflow flames calculated with the 38-step mechanism show departures from experimental measurements and detailed-chemistry computations that are roughly on the order of 10%, comparable with expected experimental uncertainties. Similar accuracy is found in comparisons of autoignition times over the range considered, except at very high temperatures, under which conditions the computations tend to overpredict induction times for all of the chemistry descriptions tested. From this 38-step mechanism, the simplification is continued by introducing steady-state approximations for the intermediate species CH3, CH4, HCO, CH3O, CH2OH, and O, leading to an 8-step reduced mechanism that provides satisfactory accuracy for all conditions tested. The flame computations indicate that thermal diffusion has a negligible influence on methanol combustion in all cases considered and that a mixture-average species

  4. Development and Validation of a Reduced DME Mechanism Applicable to Various Combustion Modes in Internal Combustion Engines

    Directory of Open Access Journals (Sweden)

    Gregory T. Chin

    2011-01-01

    Full Text Available A 28-species reduced chemistry mechanism for Dimethyl Ether (DME combustion is developed on the basis of a recent detailed mechanism by Zhao et al. (2008. The construction of reduced chemistry was carried out with automatic algorithms incorporating newly developed strategies. The performance of the reduced mechanism is assessed over a wide range of combustion conditions anticipated to occur in future advanced piston internal combustion engines, such as HCCI, SAHCCI, and PCCI. Overall, the reduced chemistry gives results in good agreement with those from the detailed mechanism for all the combustion modes tested. While the detailed mechanism by Zhao et al. (2008 shows reasonable agreement with the shock tube autoignition delay data, the detailed mechanism requires further improvement in order to better predict HCCI combustion under engine conditions.

  5. Causes of Combustion Instabilities with Passive and Active Methods of Control for practical application to Gas Turbine Engines

    Science.gov (United States)

    Cornwell, Michael D.

    Combustion at high pressure in applications such as rocket engines and gas turbine engines commonly experience destructive combustion instabilities. These instabilities results from interactions between combustion heat release, fluid mechanics and acoustics. This research explores the significant affect of unstable fluid mechanics processes in augmenting unstable periodic combustion heat release. The frequency of the unstable heat release may shift to match one of the combustors natural acoustic frequencies which then can result in significant energy exchange from chemical to acoustic energy resulting in thermoacoustic instability. The mechanisms of the fluid mechanics in coupling combustion to acoustics are very broad with many varying mechanisms explained in detail in the first chapter. Significant effort is made in understanding these mechanisms in this research in order to find commonalities, useful for mitigating multiple instability mechanisms. The complexity of combustion instabilities makes mitigation of combustion instabilities very difficult as few mitigation methods have historically proven to be very effective for broad ranges of combustion instabilities. This research identifies turbulence intensity near the forward stagnation point and movement of the forward stagnation point as a common link in what would otherwise appear to be very different instabilities. The most common method of stabilization of both premixed and diffusion flame combustion is through the introduction of swirl. Reverse flow along the centerline is introduced to transport heat and chemically active combustion products back upstream to sustain combustion. This research develops methods to suppress the movement of the forward stagnation point without suppressing the development of the vortex breakdown process which is critical to the transport of heat and reactive species necessary for flame stabilization. These methods are useful in suppressing the local turbulence at the forward

  6. Mathematical Model of Piston Ring Sealing in Combustion Engine

    Directory of Open Access Journals (Sweden)

    Koszałka Grzegorz

    2015-01-01

    Full Text Available This paper presents a mathematical model of piston-rings-cylinder sealing (TPC of a combustion engine. The developed model is an itegrated model of gas flow through gaps in TPC unit, displacements and twisting motions of piston rings in ring grooves as well as generation of oil film between ring face surfaces and cylinder liner. Thermal deformations and wear of TPC unit elements as well as heat exchange between flowing gas and surrounding walls, were taken into account in the model. The paper contains descriptions of: assumptions used for developing the model, the model itself, its numerical solution as well as its computer application for carrying out simulation tests.

  7. Mathematical Model of Piston Ring Sealing in Combustion Engine

    OpenAIRE

    Koszałka Grzegorz; Guzik Mirosław

    2015-01-01

    This paper presents a mathematical model of piston-rings-cylinder sealing (TPC) of a combustion engine. The developed model is an itegrated model of gas flow through gaps in TPC unit, displacements and twisting motions of piston rings in ring grooves as well as generation of oil film between ring face surfaces and cylinder liner. Thermal deformations and wear of TPC unit elements as well as heat exchange between flowing gas and surrounding walls, were taken into account in the model. The pape...

  8. Use of the graphical analytic methods of studying the combustion processes in the internal combustion engine combustion chamber on the basis of similarity criterion

    Directory of Open Access Journals (Sweden)

    S. V. Krasheninnikov

    2014-10-01

    Full Text Available The task of improving the economic and ecological parameters of the internal combustion engines remains topical within the frameworks of the modern engine-building technology. Since a combustion engine is a complex system combining such units as an intake manifold, combustion chamber, exhaust manifold, one of directions of the engine development is adjustment of the joint operation of its units. The specified adjustment should better be performed with the use of the so-called integral characteristics. The author means under an integral characteristic the rating plate of a unit (engine containing information about all the possible modes and conditions of its use, specifies the optimal operating range and indicates all the basic values of efficiency – reliability – environmental friendliness at each point of its field. As a rule, integral characteristics are multi-parametric. It is common practice to coordinate the field of such characteristic by similarity criteria determining the unit or engine behavior in whole.

  9. Identification and quantification analysis of nonlinear dynamics properties of combustion instability in a diesel engine.

    Science.gov (United States)

    Yang, Li-Ping; Ding, Shun-Liang; Litak, Grzegorz; Song, En-Zhe; Ma, Xiu-Zhen

    2015-01-01

    The cycling combustion instabilities in a diesel engine have been analyzed based on chaos theory. The objective was to investigate the dynamical characteristics of combustion in diesel engine. In this study, experiments were performed under the entire operating range of a diesel engine (the engine speed was changed from 600 to 1400 rpm and the engine load rate was from 0% to 100%), and acquired real-time series of in-cylinder combustion pressure using a piezoelectric transducer installed on the cylinder head. Several methods were applied to identify and quantitatively analyze the combustion process complexity in the diesel engine including delay-coordinate embedding, recurrence plot (RP), Recurrence Quantification Analysis, correlation dimension (CD), and the largest Lyapunov exponent (LLE) estimation. The results show that the combustion process exhibits some determinism. If LLE is positive, then the combustion system has a fractal dimension and CD is no more than 1.6 and within the diesel engine operating range. We have concluded that the combustion system of diesel engine is a low-dimensional chaotic system and the maximum values of CD and LLE occur at the lowest engine speed and load. This means that combustion system is more complex and sensitive to initial conditions and that poor combustion quality leads to the decrease of fuel economy and the increase of exhaust emissions.

  10. Identification and quantification analysis of nonlinear dynamics properties of combustion instability in a diesel engine

    Science.gov (United States)

    Yang, Li-Ping; Ding, Shun-Liang; Litak, Grzegorz; Song, En-Zhe; Ma, Xiu-Zhen

    2015-01-01

    The cycling combustion instabilities in a diesel engine have been analyzed based on chaos theory. The objective was to investigate the dynamical characteristics of combustion in diesel engine. In this study, experiments were performed under the entire operating range of a diesel engine (the engine speed was changed from 600 to 1400 rpm and the engine load rate was from 0% to 100%), and acquired real-time series of in-cylinder combustion pressure using a piezoelectric transducer installed on the cylinder head. Several methods were applied to identify and quantitatively analyze the combustion process complexity in the diesel engine including delay-coordinate embedding, recurrence plot (RP), Recurrence Quantification Analysis, correlation dimension (CD), and the largest Lyapunov exponent (LLE) estimation. The results show that the combustion process exhibits some determinism. If LLE is positive, then the combustion system has a fractal dimension and CD is no more than 1.6 and within the diesel engine operating range. We have concluded that the combustion system of diesel engine is a low-dimensional chaotic system and the maximum values of CD and LLE occur at the lowest engine speed and load. This means that combustion system is more complex and sensitive to initial conditions and that poor combustion quality leads to the decrease of fuel economy and the increase of exhaust emissions.

  11. Identification and quantification analysis of nonlinear dynamics properties of combustion instability in a diesel engine

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Li-Ping, E-mail: yangliping302@hrbeu.edu.cn; Ding, Shun-Liang; Song, En-Zhe; Ma, Xiu-Zhen [Institute of Power and Energy Engineering, Harbin Engineering University, No. 145-1, Nantong Street, Nangang District, Harbin 150001 (China); Litak, Grzegorz [Faculty of Mechanical Engineering, Lublin University of Technology, Nadbystrzycka 36, 20-618 Lublin (Poland)

    2015-01-15

    The cycling combustion instabilities in a diesel engine have been analyzed based on chaos theory. The objective was to investigate the dynamical characteristics of combustion in diesel engine. In this study, experiments were performed under the entire operating range of a diesel engine (the engine speed was changed from 600 to 1400 rpm and the engine load rate was from 0% to 100%), and acquired real-time series of in-cylinder combustion pressure using a piezoelectric transducer installed on the cylinder head. Several methods were applied to identify and quantitatively analyze the combustion process complexity in the diesel engine including delay-coordinate embedding, recurrence plot (RP), Recurrence Quantification Analysis, correlation dimension (CD), and the largest Lyapunov exponent (LLE) estimation. The results show that the combustion process exhibits some determinism. If LLE is positive, then the combustion system has a fractal dimension and CD is no more than 1.6 and within the diesel engine operating range. We have concluded that the combustion system of diesel engine is a low-dimensional chaotic system and the maximum values of CD and LLE occur at the lowest engine speed and load. This means that combustion system is more complex and sensitive to initial conditions and that poor combustion quality leads to the decrease of fuel economy and the increase of exhaust emissions.

  12. EXPERIMENTAL COMBUSTION ANALYSIS OF A HSDI DIESEL ENGINE FUELLED WITH PALM OIL BIODIESEL-DIESEL FUEL BLENDS

    Directory of Open Access Journals (Sweden)

    JOHN AGUDELO

    2009-01-01

    Full Text Available Differences in the chemical nature between petroleum diesel fuels and vegetable oils-based fuels lead to differences in their physical properties affecting the combustion process inside the engine. In this work a detailed combustion diagnosis was applied to a turbocharged automotive diesel engine operating with neat palm oil biodiesel (POB, No. 2 diesel fuel and their blends at 20 and 50% POB by volume (B20 and B50 respectively. To isolate the fuel effect, tests were executed at constant power output without carrying out any modification of the engine or its fuel injection system. As the POB content in the blend increased, there was a slight reduction in the fuel/air equivalence ratio from 0.39 (B0 to 0.37 (B100, an advance of injection timing and of start of combustion. Additionally, brake thermal efficiency, combustion duration, maximum mean temperature, temperature at exhaust valve opening and exhaust gas efficiency decreased; while the peak pressure, exergy destruction rate and specific fuel consumption increased. With diesel fuel and the blends B20 and B50 the same combustion stages were noticed. However, as a consequence of the differences pointed out, the thermal history of the process was affected. The diffusion combustion stage became larger with POB content. For B100 no premixed stage was observed.

  13. Investigations of Rocket Engine Combustion Emissions During ACCENT

    Science.gov (United States)

    Ross, M. N.; Friedl, R. R.

    2001-12-01

    The composition of rocket combustion emissions and the atmospheric processes that determine their stratospheric impacts are poorly understood. While present day rocket emissions do not significantly affect stratospheric chemistry, the potential for vigorous growth of the space transportation industry in coming decades suggests that rocket emissions and their stratospheric impacts should be better understood. A variety of in-situ measurements and modeling results were obtained during the Atmospheric Chemistry of Combustion Emissions Near the Tropopause (ACCENT) effort that will be used to evaluate the role of rocket exhaust in perturbing ozone chemistry in plume wakes and in the global stratosphere. We present a review of the ACCENT rocket emissions science objectives, summarize data obtained during the WB-57F plume wake sorties, and briefly discuss how the data will help resolve several outstanding questions regarding the impact of rocket emissions on the stratosphere. These include measurement of the emission indices for several important rocket engine combustion products and validation of plume wake chemistry models.

  14. Chemical Engineering in the "BIO" world

    DEFF Research Database (Denmark)

    Chiarappa, Gianluca; Grassi, Mario; Abrami, Michela

    2017-01-01

    Modern Chemical Engineering was born around the end of the 19th century in Great Britain, Germany, and the USA, the most industrialized countries at that time. Milton C. Whitaker, in 1914, affirmed that the difference between Chemistry and Chemical Engineering lies in the capability of chemical e...

  15. The influence of charge stratification on the spectral signature of partially premixed combustion in a light-duty optical engine

    KAUST Repository

    Najafabadi, M. Izadi

    2017-03-25

    The origin of light emission during low-temperature combustion in a light-duty IC engine is investigated by high-speed spectroscopy in both HCCI and PPC regimes. Chemiluminescence and thermal radiation are expected to be the dominant sources of light emission during combustion. A method has been developed to distinguish chemiluminescence from thermal radiation, and different chemiluminescing species could be identified. Different combustion modes and global equivalence ratios are analyzed in this manner. The results indicate that the spectral signature (270–540 nm range) of the combustion is highly dependent on the stratification level. A significant broadband chemiluminescence signal is detected and superimposed on all spectra. This broadband chemiluminescence signal can reach up to 100 percent of the total signal in HCCI combustion, while it drops to around 80 percent for stratified combustion (PPC). We show that this broadband signal can be used as a measure for the heat release rate. The broadband chemiluminescence did also correlate with the equivalence ratio quite well in both HCCI and PPC regimes, suggesting that the total emission in the spectral region of 330–400 nm can serve as a proxy of equivalence ratio and the rate of heat release. Regarding C2* chemiluminescence, we see two different chemical mechanisms for formation of C2* in the PPC regime: first during the early stage of combustion by the breakup of bigger molecules and the second during the late stage of combustion when soot particles are forming.

  16. The history and evolution of optically accessible research engines and their impact on our understanding of engine combustion

    Energy Technology Data Exchange (ETDEWEB)

    Miles, Paul C. [Sandia National Lab. (SNL-CA), Livermore, CA (United States)

    2015-03-01

    The development and application of optically accessible engines to further our understanding of in-cylinder combustion processes is reviewed, spanning early efforts in simplified engines to the more recent development of high-pressure, high-speed engines that retain the geometric complexities of modern production engines. Limitations of these engines with respect to the reproduction of realistic metal test engine characteristics and performance are identified, as well as methods that have been used to overcome these limitations. Finally, the role of the work performed in these engines on clarifying the fundamental physical processes governing the combustion process and on laying the foundation for predictive engine simulation is summarized.

  17. Influence of process parameters on coal combustion performance. Review, experiments and engineering modeling

    Energy Technology Data Exchange (ETDEWEB)

    Lans, R.P. van der

    1997-04-01

    The objective of this study is to improve the understanding of nitrogen oxide formation and carbon burnout during the combustion of pulverized coal, and to contribute to addressing the potential of chemical engineering models for the prediction of furnace temperatures, NO emissions and the amount of carbon in ash. To this purpose, the effect of coal quality on NO and burnout has been investigated experimentally, a radiation heat balance has been developed based on a simple chemical engineering methodology, and a mixing study has been conducted in order to describe the near burner macro mixing in terms of a reactor configuration. The influence of coal type and process conditions on NO formation and carbon burnout has been investigated experimentally in a 400 MW{sub e} corner fired boiler with over fire air, a 350 MW{sub e} opposed fired boiler, and in a 160 kW{sub t} pilot scale test rig. Three different coals were fired in each of the furnaces as part of the activities in group 3 of the European Union JOULE 2 Extension project `Atmospheric Pressure Combustion of Pulverized Coal and Coal Based Blends for Power Generation`. On the pilot scale test both single stage and air staged tests were performed. A simple, one-dimensional combustion and radiation heat transfer model has been developed for the furnace of full scale boilers. The model has been applied to the two boilers mentioned above, and is validated against measured temperatures and carbon in ash concentrations. A mixing study has been performed in order to initiate an investigation of the potential of chemical engineering models to predict NO from pulverized fuel burners. (EG) 11 refs.

  18. Combustion chemical vapor deposited coatings for thermal barrier coating systems

    Energy Technology Data Exchange (ETDEWEB)

    Hampikian, J.M.; Carter, W.B. [Georgia Institute of Technology, Atlanta, GA (United States). School of Materials Science and Engineering

    1995-12-31

    The new deposition process, combustion chemical vapor deposition, shows a great deal of promise in the area of thermal barrier coating systems. This technique produces dense, adherent coatings, and does not require a reaction chamber. Coatings can therefore be applied in the open atmosphere. The process is potentially suitable for producing high quality CVD coatings for use as interlayers between the bond coat and thermal barrier coating, and/or as overlayers, on top of thermal barrier coatings. In this report, the evaluation of alumina and ceria coatings on a nickel-chromium alloy is described.

  19. Enhanced combustion by jet ignition in a turbocharged cryogenic port fuel injected hydrogen engine

    Energy Technology Data Exchange (ETDEWEB)

    Boretti, Alberto A.; Watson, Harry C. [Department of Mechanical Engineering, The University of Melbourne, 3010 Melbourne (Australia)

    2009-03-15

    The Hydrogen Assisted Jet Ignition (HAJI) is a physico-chemical combustion enhancement system developed at the University of Melbourne. Jet ignition can ignite ultra-lean air/fuel mixtures which are far beyond the stable ignition limit of a spark plug. Jet ignition may further enhance the combustion properties of hydrogen enabling the development of a diesel-like, almost throttle-less, control of load by quantity of fuel injected for higher thermal efficiencies all over the range of loads. The object of this paper is to show the benefits of jet ignition and present the latest results obtained on a four cylinder engine having the jet ignition coupled with cryogenic hydrogen injection and turbo charging. (author)

  20. Internal combustion engine for natural gas compressor operation

    Science.gov (United States)

    Hagen, Christopher L.; Babbitt, Guy; Turner, Christopher; Echter, Nick; Weyer-Geigel, Kristina

    2016-04-19

    This application concerns systems and methods for compressing natural gas with an internal combustion engine. In a representative embodiment, a system for compressing a gas comprises a reciprocating internal combustion engine including at least one piston-cylinder assembly comprising a piston configured to travel in a cylinder and to compress gas in the cylinder in multiple compression stages. The system can further comprise a first pressure tank in fluid communication with the piston-cylinder assembly to receive compressed gas from the piston-cylinder assembly until the first pressure tank reaches a predetermined pressure, and a second pressure tank in fluid communication with the piston-cylinder assembly and the first pressure tank. The second pressure tank can be configured to receive compressed gas from the piston-cylinder assembly until the second pressure tank reaches a predetermined pressure. When the first and second pressure tanks have reached the predetermined pressures, the first pressure tank can be configured to supply gas to the piston-cylinder assembly, and the piston can be configured to compress the gas supplied by the first pressure tank such that the compressed gas flows into the second pressure tank.

  1. Combustion oscillation study in a kerosene fueled rocket-based combined-cycle engine combustor

    Science.gov (United States)

    Huang, Zhi-Wei; He, Guo-Qiang; Qin, Fei; Xue, Rui; Wei, Xiang-Geng; Shi, Lei

    2016-12-01

    This study reports the combustion oscillation features in a three-dimensional (3D) rocket-based combined-cycle (RBCC) engine combustor under flight Mach number (Mflight) 3.0 conditions both experimentally and numerically. Experiment is performed on a direct-connect ground test facility, which measures the wall pressure along the flow-path. High-speed imaging of the flame luminosity and schlieren is carried out at exit of the primary rocket. Compressible reactive large eddy simulation (LES) with reduced chemical kinetics of a surrogate model for kerosene is performed to further understand the combustion oscillation mechanisms in the combustor. LES results are validated with experimental data by the time-averaged and root mean square (RMS) pressure values, and show acceptable agreement. Effects of the primary rocket jet on pressure oscillation in the combustor are analyzed. Relation of the high speed rocket jet oscillation, which is thought to among the most probable sources of combustion oscillation, with the RBCC combustor is recognized. Results reveal that the unsteady over-expanded rocket jet has significant impacts on the combustion oscillation feature of the RBCC combustor, which is different from a thermo-acoustics type oscillation. The rocket jet/air inflow physical interactions under different rocket jet expansion degrees are experimentally studied.

  2. Autoignition and Combustion of Natural Gas in a 4 Stroke HCCI Engine

    Science.gov (United States)

    Jun, Daesu; Ishii, Kazuaki; Iida, Norimasa

    Homogeneous charge compression ignition (HCCI) is regarded as the next generation combustion regime in terms of high thermal efficiency and low emissions. It is difficult to control autoignition timing and combustion duration because they are controlled primarily by the chemical kinetics of fuel-air mixture. In this study, it was investigated the characteristics of autoignition and combustion of natural gas in a 4 stroke HCCI engine. And also, to clarify the influence of n-butane on autoignition and combustion of natural gas, it was changed the blend ratio of n-butane from 0mol% to 10mol% in methane/n-butane/air mixtures. Autoignition strongly depends on in-cylinder gas temperature. Autoignition of natural gas occurs when in-cylinder gas temperature reaches in a range of 1000±100K under this experimental condition. To realize high thermal efficiency and low CO emissions, it is necessary to prepare operation conditions that maximum cycle temperature is over 1500K. Autoignition temperature is 25K lower by increasing n-butane blend ratio of 10%. As the blend ratio of n-butane increases, the maximum cycle temperature increases, and THC, CO emissions reduce.

  3. Compression-cast light metal piston for internal combustion engines. Pressgegossener Leichtmetallkolben fuer Verbrennungskraftmaschinen

    Energy Technology Data Exchange (ETDEWEB)

    Mielke, S.; Henning, W.; Weiss, F.; Goelder, K.

    1991-05-16

    In a compression-cast light metal piston for internal combustion engines, fibre bodies made of short ceramic fibres, which are aligned parallel to a plane, are cast in. To improve the resistance to wear of the piston consisting of a heat-resistant magnesium alloy, the piston shank has a metallic, chemically or galvanically separate layer with a thickness of 10 to 30 m, and a hardness of 740 to 850 HV < 0.01, at least in the area of its friction surfaces.

  4. Protein engineering approaches to chemical biotechnology.

    Science.gov (United States)

    Chen, Zhen; Zeng, An-Ping

    2016-12-01

    Protein engineering for the improvement of properties of biocatalysts and for the generation of novel metabolic pathways plays more and more important roles in chemical biotechnology aiming at the production of chemicals from biomass. Although widely used in single-enzyme catalysis process, protein engineering is only being increasingly explored in recent years to achieve more complex in vitro and in vivo biocatalytic processes. This review focuses on major contributions of protein engineering to chemical biotechnology in the field of multi-enzymatic cascade catalysis and metabolic engineering. Especially, we discuss and highlight recent strategies for combining pathway design and protein engineering for the production of novel products.

  5. Effect of chemical and physical properties on combustion of biomass particle

    OpenAIRE

    Biswas, Amit

    2015-01-01

    Biomass combustion is an interesting alternative to fossil fuel. Modeling and simulation is used for design optimization of biomass boilers and furnace. It is difficult to develop a sufficiently accurate and computationally efficient model because the combustion system is highly complicated multi-scale, multi-phase and multi-physics problem. The study of biomass combustion in different scales allows engineers to understand the combustion process and tochoose necessary simplification to develo...

  6. THE COMBUSTION ACTION VERIFICATION AND ESTIMATE OF COMBUSTION EFFICIENCY IN AVIATION GAS#TURBINE ENGINE COMBUSTION CHAMBERS

    OpenAIRE

    2011-01-01

    Verification results of combustion action simulating and estimate of calculation combustion efficiency that was given by simulating were shown. Mathematical model and its assumption are described. Execution calculations method was shown. Results of simulating are shown; their comparative analyses with results of experiment were executed. Accuracy of combustion action mathematical modeling by combustion efficiency in model with oneand two-stage reactions of combustion was estimated. The infere...

  7. EMISSION AND COMBUSTION CHARACTERISTICS OF DIFFERENT FUELS IN A HCCI ENGINE

    Directory of Open Access Journals (Sweden)

    S. Sendilvelan

    2011-06-01

    Full Text Available Different intake valve timings and fuel injection amounts were tested in order to identify their effects on exhaust emissions and combustion characteristics using variable valve actuation (VVA in a Homogeneous Charge Compression Ignition (HCCI engine. The HCCI engine is a promising concept for future automobile engines and stationary power plants. The two-stage ignition process in a HCCI engine creates advanced ignition and stratified combustion, which makes the ignition timing and combustion rate controllable. Meanwhile, the periphery of the fuel-rich zone leads to fierce burning, which results in slightly high NOx emissions. The experiments were conducted in a modified single cylinder water-cooled diesel engine. In this experiment we use diesel, bio-diesel (Jatropha and gasoline as the fuel at different mixing ratios. HCCI has advantages in high thermal efficiency and low emissions and could possibly become a promising combustion method in internal combustion engines.

  8. Chemical Engineering in the "BIO" world.

    Science.gov (United States)

    Chiarappa, Gianluca; Grassi, Mario; Abrami, Michela; Abbiati, Roberto Andrea; Barba, Anna Angela; Boisen, Anja; Brucato, Valerio; Ghersi, Giulio; Caccavo, Diego; Cascone, Sara; Caserta, Sergio; Elvassore, Nicola; Giomo, Monica; Guido, Stefano; Lamberti, Gaetano; Larobina, Domenico; Manca, Davide; Marizza, Paolo; Tomaiuolo, Giovanna; Grassi, Gabriele

    2016-06-02

    Modern Chemical Engineering was born around the end of the 19th century in Great Britain, Germany, and the USA, the most industrialized countries at that time. Milton C. Whitaker, in 1914, affirmed that the difference between Chemistry and Chemical Engineering lies in the capability of chemical engineers to transfer laboratory findings to the industrial level. Since then, Chemical Engineering underwent huge transformations determining the detachment from the original Chemistry nest. The beginning of the sixties of the 20th century saw the development of a new branch of Chemical Engineering baptized Biomedical Engineering by Peppas and Langer and that now we can name Biological Engineering. Interestingly, although Biological Engineering focused on completely different topics from Chemical Engineering ones, it resorted to the same theoretical tools such as, for instance, mass, energy and momentum balances. Thus, the birth of Biological Engineering may be considered as a Darwinian evolution of Chemical Engineering similar to that experienced by mammals which, returning to water, used legs and arms to swim. From 1960 on, Biological Engineering underwent a considerable evolution as witnessed by the great variety of topics covered such as hemodialysis, release of synthetic drugs, artificial organs and, more recently, delivery of small interfering RNAs (siRNA). This review, based on the activities developed in the frame of our PRIN 2010-11 (20109PLMH2) project, tries to recount origins and evolution of Chemical Engineering illustrating several examples of recent and successful applications in the biological field. This, in turn, may stimulate the discussion about the Chemical Engineering students curriculum studiorum update.

  9. Carbon Capture via Chemical-Looping Combustion and Reforming

    Energy Technology Data Exchange (ETDEWEB)

    Johansson, Marcus; Mattisson, Tobias; Ryden, Magnus; Lyngfelt, Anders

    2006-10-15

    Chemical-looping combustion (CLC) is a combustion technology with inherent separation of the greenhouse gas CO{sub 2}. The technique involves the use of a metal oxide as an oxygen carrier which transfers oxygen from combustion air to the fuel, and hence a direct contact between air and fuel is avoided. Two inter-connected fluidized beds, a fuel reactor and an air reactor, are used in the process. In the fuel reactor, the metal oxide is reduced by the reaction with the fuel and in the air reactor; the reduced metal oxide is oxidized with air. The outlet gas from the fuel reactor consists of CO{sub 2} and H{sub 2}O, and almost pure stream of CO{sub 2} is obtained when water is condensed. Considerable research has been conducted on CLC in the last decade with respect to oxygen carrier development, reactor design, system efficiencies and prototype testing. The technique has been demonstrated successfully with both natural gas and syngas as fuel in continuous prototype reactors based on interconnected fluidized beds within the size range 0.3 - 50 kW, using different types of oxygen carriers based on the metals Ni, Co, Fe, Cu and Mn. From these tests it can be established that almost complete conversion of the fuel can be obtained and 100% CO{sub 2} capture is possible. Further, two different types of chemical-looping reforming (CLR) have been presented in recent years. CLR is a technology to produce hydrogen with inherent CO{sub 2} capture. This paper presents an overview of the research performed on CLC and CLR highlights the current status of the technology.

  10. OPTIMUM PLANNING OF EXPERIMENTS AT MODELING FUEL CONSUMPTION IN INTERNAL COMBUSTION ENGINES

    Directory of Open Access Journals (Sweden)

    N. Koshevoy

    2009-01-01

    Full Text Available The efficiency of optimum experiments planning by cost expenses at studying the processes of fuel consumption internal combustion engines is shown. The mathematical models of these processes in different state of engine working are synthesized.

  11. Concept for lowest emissions of a hydrogen internal combustion engine; Niedrigstemissionskonzept fuer einen wasserstoffbetriebenen Verbrennungsmotor

    Energy Technology Data Exchange (ETDEWEB)

    Fouquet, Marcel Christian Thomas

    2012-03-15

    This paper describes a concept with lowest emissions for a hydrogen internal combustion engine for passenger cars. With optimisation of the combustion concept the level of nitrogen oxide is below 90%, hydrocarbon and carbon monoxide below 99% of the SULEV target (CARB). This concept enables a potential in power density that is comparable to current supercharged combustion engines at lowest emission level without catalytic aftertreatment. Additionally with a catalytic aftertreatment system, the emission level of a current hydrogen combustion engine (mono-fuel) is lowered to a level, that this car can be labeled as air cleaning vehicle for hydrocarbons and carbon monoxide.

  12. Recurrence plot for parameters analysing of internal combustion engine

    Science.gov (United States)

    Alexa, O.; Ilie, C. O.; Marinescu, M.; Vilau, R.; Grosu, D.

    2015-11-01

    In many technical disciplines modem data analysis techniques has been successfully applied to understand the complexity of the system. The growing volume of theoretical knowledge about systems dynamic's offered researchers the opportunity to look for non-linear dynamics in data whose evolution linear models are unable to explain in a satisfactory manner. One approach in this respect is Recurrence Analysis - RA which is a graphical method designed to locate hidden recurring patterns, nonstationarity and structural changes. RA approach arose in natural sciences like physics and biology but quickly was adopted in economics and engineering. Meanwhile. The fast development of computer resources has provided powerful tools to perform this new and complex model. One free software which was used to perform our analysis is Visual Recurrence Analysis - VRA developed by Eugene Kononov. As is presented in this paper, the recurrence plot investigation for the analyzing of the internal combustion engine shows some of the RPA capabilities in this domain. We chose two specific engine parameters measured in two different tests to perform the RPA. These parameters are injection impulse width and engine angular speed and the tests are I11n and I51n. There were computed graphs for each of them. Graphs were analyzed and compared to obtain a conclusion. This work is an incipient research, being one of the first attempts of using recurrence plot for analyzing automotive dynamics. It opens a wide field of action for future research programs.

  13. Combustion instability investigations on the BR710 jet engine

    Energy Technology Data Exchange (ETDEWEB)

    Konrad, W.; Brehm, N.; Kameier, F. [BMW Rolls-Royce AeroEngines, Dahlewitz (Germany); Freeman, C. [Rolls-Royce PLC, Derby (United Kingdom). Advanced Propulsion Systems; Day, I.J. [Cambridge Univ. (United Kingdom). Whittle Lab.

    1998-01-01

    During the development of the BR710 jet engine, audible combustor instabilities (termed rumble) occurred. Amplitudes measured with test cell microphones were up to 130 dB at around 100 Hz. Disturbances of this amplitude are clearly undesirable, even if only present during start-up, and a research program was initiated to eliminate the problem. Presented here is the methodical and structured approach used to identify, understand, and remove the instability. Some reference is made to theory, which was used for guidance, but the focus of the work is on the research done to find the cause of the problem and to correct it. The investigation followed two separate, but parallel, paths--one looking in detail at individual components of the engine to identify possible involvement in the instability and the other looking at the pressure signals from various parts of a complete engine to help pinpoint the source of the disturbance. The main cause of the BR710 combustor rumble was found to be a self-excited aerodynamic instability arising from the design of the fuel injector head. In the end, minor modifications lead to spray pattern changes, which greatly reduced the combustor noise. As a result of this work, new recommendation are made for reducing the risk of combustion instabilities in jet engines.

  14. An overview of NASA intermittent combustion engine research

    Science.gov (United States)

    Willis, E. A.; Wintucky, W. T.

    1984-01-01

    This paper overviews the current program, whose objective is to establish the generic technology base for advanced aircraft I.C. engines of the early 1990's and beyond. The major emphasis of this paper is on development of the past two years. Past studies and ongoing confirmatory experimental efforts are reviewed, which show unexpectedly high potential when modern aerospace technologies are applied to inherently compact and balanced I.C. engine configurations. Currently, the program is focussed on two engine concepts, the stratified-charge, multi-fuel rotary and the lightweight two-stroke diesel. A review is given of contracted and planned high performance one-rotor and one-cylinder test engine work addressing several levels of technology. Also reviewed are basic supporting efforts, e.g., the development and experimental validation of computerized airflow and combustion process models, being performed in-house at Lewis Research Center and by university grants. Previously announced in STAR as N84-24583

  15. Chemical engineering: Measurements for a competitive age

    Science.gov (United States)

    1986-01-01

    The NIST (National Institute of Standards and Technology) activities supporting chemical research, environmental research, combustion and fuel research, and related industries are described in this video. Highlights include private sector involvement in the research and associated and guest scientist programs, the calibration of customers' instruments, and the direct funding for the NIST research projects by outside industries.

  16. Turbulence, combustion, efficiency and emission measurements on a supercharged natural gas SI engine

    Energy Technology Data Exchange (ETDEWEB)

    Einewall, P.; Olsson, Magnus

    1996-08-01

    LDV was used to measure turbulence in six different combustion chambers for a natural gas operated TD102 Volvo truck engine. The efficiency and emissions were measured during supercharged lean operation. The combustion chambers were altered by using pistons with different crown geometries. Some of the load cases require supercharged operation of the engine. The cooling of the cylinder-head was therefore improved. Turbulence, combustion rate, emissions and efficiency was measured for four different piston design. 8 refs, figs

  17. Nonlinear theory of combustion stability in liquid rocket engine based on chemistry dynamics

    Institute of Scientific and Technical Information of China (English)

    黄玉辉; 王振国; 周进

    2002-01-01

    Detailed models of combustion instability based on chemistry dynamics are developed. The results show that large activation energy goes against the combustion stability. The heat transfer coefficient between the wall and the combust gas is an important bifurcation parameter for the combustion instability. The acoustics modes of the chamber are in competition and cooperation with each other for limited vibration energy. Thermodynamics criterion of combustion stability can be deduced from the nonlinear thermodynamics. Correlations of the theoretical results and historical experiments indicate that chemical kinetics play a critical role in the combustion instability.

  18. FY2011 Annual Progress Report for Advanced Combustion Engine Research and Development

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2011-12-01

    Annual Progress Report for the Advanced Combustion Engine Research and Development (R&D) subprogram supporting the mission of the Vehicle Technologies Program by removing the critical technical barriers to commercialization of advanced internal combustion engines (ICEs) for passenger and commercial vehicles that meet future federal emissions regulations.

  19. Digital signal processing of cylinder pressure data for combustion diagnostics of HCCI engine

    Science.gov (United States)

    Kumar Maurya, Rakesh; Pal, Dev Datt; Kumar Agarwal, Avinash

    2013-03-01

    Diagnosis of combustion is necessary for the estimation of the combustion quality, and control of combustion timing in advanced combustion concepts like HCCI. Combustion diagnostics is often performed using digital processing of pressure signals measured using piezoelectric sensor installed in the combustion chamber of the engine. Four-step pressure signal processing consisting of (i) absolute pressure correction, (ii) phasing w.r.t. crank angle, (iii) cycle averaging and (iv) smoothening is used to get cylinder pressure data from the engine experiments, which is further analyzed to get information about combustion characteristics. This study focuses on various aspect of signal processing (cycle averaging and smoothing) of in-cylinder pressure signal from a HCCI engine acquired using a piezoelectric pressure sensor. Experimental investigations are conducted on a HCCI combustion engine operating at different engine speed/load/air-fuel ratio conditions. The cylinder pressure history of 3000 consecutive engine cycles is acquired for analysis using piezoelectric pressure sensor. This study determines the optimum number of engine cycles to be acquired for reasonably good pressure signals based on standard deviation of in-cylinder pressure, rate of pressure rise and rate of heat release signals. Different signal smoothening methods (using various digital filters) are also analyzed and their results are compared. This study also presents effect of signal processing methods on pressure, pressure rise rate and rate of heat release curves at different engine operating conditions.

  20. Combustion process evaluation in Diesel engines using the Second law analysis; Avaliacao do processo de combustao em motores diesel usando analise de segunda lei

    Energy Technology Data Exchange (ETDEWEB)

    Alegre, Jose Velasquez; Milanez, Luiz Fernando [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Mecanica. Dept. de Energia

    1990-12-31

    Exergy balance equations are applied to a thermodynamic model in order to evaluate the combustion process for diesel engines. Thermomechanical and chemical availabilities are determined as well as the irreversibility produced. Finally the model is used to analyze experimental data obtained for a single cylinder diesel engine, at full load condition. (author) 14 refs., 6 figs., 2 tabs.

  1. Optical Study of Flow and Combustion in an HCCI Engine with Negative Valve Overlap

    Science.gov (United States)

    Wilson, Trevor S.; Xu, Hongming; Richardson, Steve; Wyszynski, Miroslaw L.; Megaritis, Thanos

    2006-07-01

    One of the most widely used methods to enable Homogeneous Charge Compression Ignition (HCCI) combustion is using negative valve overlapping to trap a sufficient quantity of hot residual gas. The characteristics of air motion with specially designed valve events having reduced valve lift and durations associated with HCCI engines and their effect on subsequent combustion are not yet fully understood. In addition, the ignition process and combustion development in such engines are very different from those in conventional spark-ignition or diesel compression ignition engines. Very little data has been reported concerning optical diagnostics of the flow and combustion in the engine using negative valve overlapping. This paper presents an experimental investigation into the in-cylinder flow characteristics and combustion development in an optical engine operating in HCCI combustion mode. PIV measurements have been taken under motored engine conditions to provide a quantitative flow characterisation of negative valve overlap in-cylinder flows. The ignition and combustion process was imaged using a high resolution charge coupled device (CCD) camera and the combustion imaging data was supplemented by simultaneously recorded in-cylinder pressure data which assisted the analysis of the images. It is found that the flow characteristics with negative valve overlapping are less stable and more valve event driven than typical spark ignition in-cylinder flows, while the combustion initiation locations are not uniformly distributed.

  2. Computational Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Westbrook, C K; Mizobuchi, Y; Poinsot, T J; Smith, P J; Warnatz, J

    2004-08-26

    Progress in the field of computational combustion over the past 50 years is reviewed. Particular attention is given to those classes of models that are common to most system modeling efforts, including fluid dynamics, chemical kinetics, liquid sprays, and turbulent flame models. The developments in combustion modeling are placed into the time-dependent context of the accompanying exponential growth in computer capabilities and Moore's Law. Superimposed on this steady growth, the occasional sudden advances in modeling capabilities are identified and their impacts are discussed. Integration of submodels into system models for spark ignition, diesel and homogeneous charge, compression ignition engines, surface and catalytic combustion, pulse combustion, and detonations are described. Finally, the current state of combustion modeling is illustrated by descriptions of a very large jet lifted 3D turbulent hydrogen flame with direct numerical simulation and 3D large eddy simulations of practical gas burner combustion devices.

  3. Piston surface heat transfer during combustion in large marine diesel engines

    DEFF Research Database (Denmark)

    Jensen, Michael Vincent; Walther, Jens Honore

    2010-01-01

    In the design process of large marine diesel engines information on the maximum heat load on the piston surface experienced during the engine cycle is an important parameter. The peak heat load occurs during combustion when hot combustion products impinge on the piston surface. Although the maximum...... with burning off piston surface material. In this work the peak heat load on the piston surface of large marine diesel engines during combustion was investigated. Measurements of the instantaneous surface temperature and surface heat flux on pistons in large marine engines are difficult due to expensive...... was calculated under different conditions in the numerical setup in order to obtain information of the actual peak heat flux experienced at the piston in large marine diesel engines during combustion. The variation of physical parameters influencing the heat transfer during combustion included a variation...

  4. Heat Exchanger Lab for Chemical Engineering Undergraduates

    Science.gov (United States)

    Rajala, Jonathan W.; Evans, Edward A.; Chase, George G.

    2015-01-01

    Third year chemical engineering undergraduate students at The University of Akron designed and fabricated a heat exchanger for a stirred tank as part of a Chemical Engineering Laboratory course. The heat exchanger portion of this course was three weeks of the fifteen week long semester. Students applied concepts of scale-up and dimensional…

  5. Study of combustion and emission characteristics of turbocharged diesel engine fuelled with dimethylether

    Institute of Scientific and Technical Information of China (English)

    Junhua WU; Zhen HUANG; Xinqi QIAO; Jun LU; Junjun ZHANG; Liang ZHANG

    2008-01-01

    An experimental study of a turbocharged diesel engine operating on dimethyl ether (DME) was conducted. The combustion and emission characteristics of the DME engine were investigated. The results show that the maximum torque and power of DME are greater than those of diesel, particularly at low speeds; the brake specific fuel consum-ption of DME is lower than that of diesel at low and middle engine speeds, and the injection delay of DME is longer than that of diesel. However, the maximum cylinder pressure, maximum pressure rise rate and combustion noises of the DME engine are lower than those of diesel. The combustion velocity of DME is faster than that of diesel, resulting in a shorter combustion duration of DME. Compared with the diesel engine, NOx emission of the DME engine is reduced by 41.6% on ESC data. In addition, the DME engine is smoke free at any operating condition.

  6. Ecological optimization of endoreversible chemical engines

    Directory of Open Access Journals (Sweden)

    Dan Xia, Lingen Chen, Fengrui Sun

    2011-09-01

    Full Text Available Optimal ecological performances of endoreversible chemical engine cycles with both linear and diffusive mass transfer laws are derived by taking an ecological optimization criterion as the objective, which consists of maximizing a function representing the best compromise between the power output and entropy production rate of the chemical engines. Numerical examples are given to show the effects of mass-reservoir chemical potential ratio and mass-transfer coefficient ratio on the ecological function versus the efficiency characteristic of the cycles. The results can provide some theoretical guidelines for the design of practical chemical engines.

  7. Multidimensional modeling of Dimethyl Ether(DME) spray combustion in DI diesel engine

    Institute of Scientific and Technical Information of China (English)

    WEN Hua; LIU Yong-chang; WEI Ming-rui; ZHANG Yu-sheng

    2005-01-01

    In the present study a modified CFD code KIVA3V was used to simulate the spray combustion in a small DI diesel engine fueled with DME. The improved spray models consider more spray phenomena such as cavitation flow in nozzle hole, jet atomization, droplet second breakup and spray wall interaction. Otherwise, a reduced DME reaction mechanism is implemented in the combustion model, and a new turbulent combustion model-Partial Stirred Reactor (PaSR) model is selected to simulate the spray combustion process, the effects of turbulent mixing on the reaction rate are considered. The results of engine modeling based on those models agreed well with the experimental measurements. Study of temperature fields variation and particle traces in the combustion chamber revealed that the engine combustion system originally used for diesel fuel must be optimized for DME.

  8. A computational investigation of diesel and biodiesel combustion and NOx formation in a light-duty compression ignition engine

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zihan [Mississippi State Univ., Mississippi State, MS (United States). Dept. of Mechanical Engineering; Srinivasan, Kalyan K. [Mississippi State Univ., Mississippi State, MS (United States). Dept. of Mechanical Engineering; Krishnan, Sundar R. [Mississippi State Univ., Mississippi State, MS (United States). Dept. of Mechanical Engineering; Som, Sibendu [Argonne National Lab. (ANL), Argonne, IL (United States). Center for Transportation Research

    2012-04-24

    Diesel and biodiesel combustion in a multi-cylinder light duty diesel engine were simulated during a closed cycle (from IVC to EVO), using a commercial computational fluid dynamics (CFD) code, CONVERGE, coupled with detailed chemical kinetics. The computational domain was constructed based on engine geometry and compression ratio measurements. A skeletal n-heptane-based diesel mechanism developed by researchers at Chalmers University of Technology and a reduced biodiesel mechanism derived and validated by Luo and co-workers were applied to model the combustion chemistry. The biodiesel mechanism contains 89 species and 364 reactions and uses methyl decanoate, methyl-9- decenoate, and n-heptane as the surrogate fuel mixture. The Kelvin-Helmholtz and Rayleigh-Taylor (KH-RT) spray breakup model for diesel and biodiesel was calibrated to account for the differences in physical properties of the fuels which result in variations in atomization and spray development characteristics. The simulations were able to capture the experimentally observed pressure and apparent heat release rate trends for both the fuels over a range of engine loads (BMEPs from 2.5 to 10 bar) and fuel injection timings (from 0° BTDC to 10° BTDC), thus validating the overall modeling approach as well as the chemical kinetic models of diesel and biodiesel surrogates. Moreover, quantitative NOx predictions for diesel combustion and qualitative NOx predictions for biodiesel combustion were obtained with the CFD simulations and the in-cylinder temperature trends were correlated to the NOx trends.

  9. Progress in reforming chemical engineering education.

    Science.gov (United States)

    Wankat, Phillip C

    2013-01-01

    Three successful historical reforms of chemical engineering education were the triumph of chemical engineering over industrial chemistry, the engineering science revolution, and Engineering Criteria 2000. Current attempts to change teaching methods have relied heavily on dissemination of the results of engineering-education research that show superior student learning with active learning methods. Although slow dissemination of education research results is probably a contributing cause to the slowness of reform, two other causes are likely much more significant. First, teaching is the primary interest of only approximately one-half of engineering faculty. Second, the vast majority of engineering faculty have no training in teaching, but trained professors are on average better teachers. Significant progress in reform will occur if organizations with leverage-National Science Foundation, through CAREER grants, and the Engineering Accreditation Commission of ABET-use that leverage to require faculty to be trained in pedagogy.

  10. A new theory of chemical method to prevent spontaneous combustion of coal

    Institute of Scientific and Technical Information of China (English)

    LU Wei

    2009-01-01

    In order to prevent spontaneous combustion of coal from the source, based on the study on the mechanism of spontaneous combustion of coal, especially the process of coal to self-ignite and different activate structures have different activation for oxidization, the new theory and mechanism with chemical inhibition that can change the tendency of spontaneous combustion of coal and let the activate structures deactivate were brought forward. Therefore, coal was not self-ignited under a certain temperature when being chemically inhibited.

  11. Internal combustion engine report: Spark ignited ICE GenSet optimization and novel concept development

    Energy Technology Data Exchange (ETDEWEB)

    Keller, J.; Blarigan, P. Van [Sandia National Labs., Livermore, CA (United States)

    1998-08-01

    In this manuscript the authors report on two projects each of which the goal is to produce cost effective hydrogen utilization technologies. These projects are: (1) the development of an electrical generation system using a conventional four-stroke spark-ignited internal combustion engine generator combination (SI-GenSet) optimized for maximum efficiency and minimum emissions, and (2) the development of a novel internal combustion engine concept. The SI-GenSet will be optimized to run on either hydrogen or hydrogen-blends. The novel concept seeks to develop an engine that optimizes the Otto cycle in a free piston configuration while minimizing all emissions. To this end the authors are developing a rapid combustion homogeneous charge compression ignition (HCCI) engine using a linear alternator for both power take-off and engine control. Targeted applications include stationary electrical power generation, stationary shaft power generation, hybrid vehicles, and nearly any other application now being accomplished with internal combustion engines.

  12. Chemical Processes Related to Combustion in Fluidised Bed

    Energy Technology Data Exchange (ETDEWEB)

    Steenari, Britt-Marie; Lindqvist, Oliver [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Environmental Inorganic Chemistry

    2002-12-01

    with evaluation of other biomass ash particles and, as an extension, the speciation of Cu and Zn will be studied as well. Ash fractions from combustion of MSW in a BFB boiler have been investigated regarding composition and leaching properties, i.e. environmental impact risks. The release of salts from the cyclone ash fraction can be minimised by the application of a simple washing process, thus securing that the leaching of soluble substances stays within the regulative limits. The MSW ash - water systems contain some interesting chemical issues, such as the interactions between Cr(VI) and reducing substances like Al-metal. The understanding of such chemical processes is important since it gives a possibility to predict effects of a change in ash composition. An even more detailed understanding of interactions between a solution containing ions and particle surfaces can be gained by theoretical modelling. In this project (and with additional unding from Aangpannefoereningens Forskningsstiftelse) a theoretical description of ion-ion interactions and the solid-liquid-interface has been developed. Some related issues are also included in this report. The publication of a paper on the reactions of ammonia in the presence of a calcining limestone surface is one of them. A review paper on the influence of combustion conditions on the properties of fly ash and its applicability as a cement replacement in concrete is another. The licentiate thesis describing the sampling and measurement of Cd in flue gas is also included since it was finalised during the present period. A co-operation project involving the Geology Dept. at Goeteborg Univ. and our group is briefly discussed. This project concerns the utilisation of granules produced from wood ash and dolomite as nutrient source for forest soil. Finally, the plans for our flue gas simulator facility are discussed.

  13. Numerical Analysis of Autoignition and Combustion of n-Butane and Air Mixture in Homogeneous-Charge Compression-Ignition Engine Using Elementary Reactions

    Science.gov (United States)

    Yamasaki, Yudai; Iida, Norimasa

    The present study focuses on clarifying the combustion mechanism of the homogeneous-charge compression-ignition (HCCI) engine in order to control ignition and combustion as well as to reduce HC and CO emissions and to maintain high combustion efficiency by calculating the chemical kinetics of elementary reactions. For the calculations, n-butane was selected as fuel since it is a fuel with the smallest carbon number in the alkane family that shows two-stage autoignition (heat release with low-temperature reaction (LTR) and with high-temperature reaction (HTR)) similarly to higher hydrocarbons such as gasoline. The CHEMKIN code was used for the calculations assuming zero dimensions in the combustion chamber and adiabatic change. The results reveal the heat release mechanism of the LTR and HTR, the control factor of ignition timing and combustion speed, and the condition need to reduce HC and CO emissions and to maintain high combustion efficiency.

  14. Development of a self-ignition and combustion model for diesel engines; Modelisation de l`auto-inflammation et de la combustion pour les moteurs diesel

    Energy Technology Data Exchange (ETDEWEB)

    Pires Da Cruz, A.

    1997-12-09

    The work concerns self-ignition and combustion modelling in Diesel engines. Special attention is given to turbulence induced effects. Only gas fuel injection is taken into account. Turbulent mixing is identified as one of the main parameters controlling self-ignition in Diesel engines. However, turbulence effects are often neglected by models currently used in engine calculation codes. A new model based on results obtained by direct numerical simulation (DNS) is proposed. It includes turbulence effects by means of the scalar dissipation rate and presumed pdf of the mixture fraction and a chemical reaction progress variable. The model is validated through several steps. First, its results are compared to DNS in simple mixing and self-ignition cases. Then, its averaged version is integrated into the KIVA2-MB calculation code, where its behavior is tested in a one dimensional version and compared to other formulations. Finally, the model is validated with comparisons to experimental results of methane injection into a high pressure combustion chamber filled with hot air. The combustion chamber allows large optical access and therefore, optical diagnostics can be made. (author) 101 refs.

  15. Chemical looping combustion. Fuel conversion with inherent CO2 capture

    Energy Technology Data Exchange (ETDEWEB)

    Brandvoll, Oeyvind

    2005-07-01

    Chemical looping combustion (CLC) is a new concept for fuel energy conversion with CO2 capture. In CLC, fuel combustion is split into separate reduction and oxidation processes, in which a solid carrier is reduced and oxidized, respectively. The carrier is continuously recirculated between the two vessels, and hence direct contact between air and fuel is avoided. As a result, a stoichiometric amount of oxygen is transferred to the fuel by a regenerable solid intermediate, and CLC is thus a variant of oxy-fuel combustion. In principle, pure CO2 can be obtained from the reduction exhaust by condensation of the produced water vapour. The thermodynamic potential and feasibility of CLC has been studied by means of process simulations and experimental studies of oxygen carriers. Process simulations have focused on parameter sensitivity studies of CLC implemented in 3 power cycles; CLC-Combined Cycle, CLC-Humid Air Turbine and CLC-Integrated Steam Generation. Simulations indicate that overall fuel conversion ratio, oxidation temperature and operating pressure are among the most important process parameters in CLC. A promising thermodynamic potential of CLC has been found, with efficiencies comparable to, - or better than existing technologies for CO2 capture. The proposed oxygen carrier nickel oxide on nickel spinel (NiONiAl) has been studied in reduction with hydrogen, methane and methane/steam as well as oxidation with dry air. It has been found that at atmospheric pressure and temperatures above 600 deg C, solid reduction with dry methane occurs with overall fuel conversion of 92%. Steam methane reforming is observed along with methane cracking as side reactions, yielding an overall selectivity of 90% with regard to solid reduction. If steam is added to the reactant fuel, coking can be avoided. A methodology for long-term investigation of solid chemical activity in a batch reactor is proposed. The method is based on time variables for oxidation. The results for Ni

  16. Systems metabolic engineering for chemicals and materials.

    Science.gov (United States)

    Lee, Jeong Wook; Kim, Tae Yong; Jang, Yu-Sin; Choi, Sol; Lee, Sang Yup

    2011-08-01

    Metabolic engineering has contributed significantly to the enhanced production of various value-added and commodity chemicals and materials from renewable resources in the past two decades. Recently, metabolic engineering has been upgraded to the systems level (thus, systems metabolic engineering) by the integrated use of global technologies of systems biology, fine design capabilities of synthetic biology, and rational-random mutagenesis through evolutionary engineering. By systems metabolic engineering, production of natural and unnatural chemicals and materials can be better optimized in a multiplexed way on a genome scale, with reduced time and effort. Here, we review the recent trends in systems metabolic engineering for the production of chemicals and materials by presenting general strategies and showcasing representative examples.

  17. Abnormal combustion caused by lubricating oil in high BMEP gas engines

    Energy Technology Data Exchange (ETDEWEB)

    Yasueda, Shinji [Kyushu Univ. (Japan). GDEC Gas and Diesel Engine; Takasaki, Koji; Tajima, Hiroshi [Kyushu Univ. (Japan). Lab. of Engine and Combustion (ECO)

    2013-05-15

    In recent years, abnormal combustion with high peak firing pressure has been experienced on gas engines with high brake mean effective pressures. The abnormality is detected not as pre-ignition but as knocking. Research, including visualisation tests on a single-cylinder engine, has confirmed the phenomenon to be pre-ignition caused by the auto-ignition of in-cylinder lubricant, causing cyclical variations of peak firing pressure on premix combustion gas engines. (orig.)

  18. The Scaling of Performance and Losses in Miniature Internal Combustion Engines

    Science.gov (United States)

    2010-01-01

    of geometries. 53 54 Some work suggests that the combustion process in hobby engines occurs in a mixed HCCI and flame propagation regime. 55... HCCI engine during the combustion phase of the cycle. Mechanical friction was assumed to be solely because of the fluid friction in the piston–cylinder...minimum size of an engine operating on a liquid hydrocarbon fuel in HCCI mode was found to be between 0.3 and 0.4 cc while operating with a

  19. Heat transfer in rocket engine combustion chambers and nozzles

    Science.gov (United States)

    Anderson, P. G.; Cheng, G. C.; Farmer, R. C.

    1993-01-01

    Complexities of liquid rocket engine heat transfer which involve the injector faceplate and regeneratively and film cooled walls are being investigated by computational analysis. A conjugate heat transfer analysis will be used to describe localized heating phenomena associated with particular injector configurations and coolant channels and film coolant dumps. These components are being analyzed, and the analyses verified with appropriate test data. Finally, the component analyses will be synthesized into an overall flowfield/heat transfer model. The FDNS code is being used to make the component analyses. Particular attention is being given to the representation of the thermodynamic properties of the fluid streams and to the method of combining the detailed models to represent overall heating. Unit flow models of specific coaxial injector elements have been developed and will be described. Since test data from the NLS development program are not available, new validation heat transfer data have been sought. Suitable data were obtained from a Rocketdyne test program on a model hydrocarbon/oxygen engine. Simulations of these test data will be presented. Recent interest in the hybrid motor have established the need for analyses of ablating solid fuels in the combustion chamber. Analysis of a simplified hybrid motor will also be presented.

  20. Modeling of NO sensitization of IC engines surrogate fuels auto-ignition and combustion

    CERN Document Server

    Anderlohr, Jörg; Bounaceur, Roda; Battin-Leclerc, Frédérique

    2009-01-01

    This paper presents a new chemical kinetic model developed for the simulation of auto-ignition and combustion of engine surrogate fuel mixtures sensitized by the presence of NOx. The chemical mechanism is based on the PRF auto-ignition model (n-heptane/iso-octane) of Buda et al. [1] and the NO/n-butane/n-pentane model of Glaude et al. [2]. The later mechanism has been taken as a reference for the reactions of NOx with larger alcanes (n-heptane, iso-octane). A coherent two components engine fuel surrogate mechanism has been generated which accounts for the influence of NOx on auto-ignition. The mechanism has been validated for temperatures between 700 K and 1100 K and pressures between 1 and 10 atm covering the temperature and pressure ranges characteristic of engine post-oxidation thermodynamic conditions. Experiments used for validation include jet stirred reactor conditions for species evolution as a function of temperature, as well as diesel HCCI engine experiments for auto-ignition delay time measurements...

  1. Signal Processing Methods for Liquid Rocket Engine Combustion Stability Assessments

    Science.gov (United States)

    Kenny, R. Jeremy; Lee, Erik; Hulka, James R.; Casiano, Matthew

    2011-01-01

    The J2X Gas Generator engine design specifications include dynamic, spontaneous, and broadband combustion stability requirements. These requirements are verified empirically based high frequency chamber pressure measurements and analyses. Dynamic stability is determined with the dynamic pressure response due to an artificial perturbation of the combustion chamber pressure (bomb testing), and spontaneous and broadband stability are determined from the dynamic pressure responses during steady operation starting at specified power levels. J2X Workhorse Gas Generator testing included bomb tests with multiple hardware configurations and operating conditions, including a configuration used explicitly for engine verification test series. This work covers signal processing techniques developed at Marshall Space Flight Center (MSFC) to help assess engine design stability requirements. Dynamic stability assessments were performed following both the CPIA 655 guidelines and a MSFC in-house developed statistical-based approach. The statistical approach was developed to better verify when the dynamic pressure amplitudes corresponding to a particular frequency returned back to pre-bomb characteristics. This was accomplished by first determining the statistical characteristics of the pre-bomb dynamic levels. The pre-bomb statistical characterization provided 95% coverage bounds; these bounds were used as a quantitative measure to determine when the post-bomb signal returned to pre-bomb conditions. The time for post-bomb levels to acceptably return to pre-bomb levels was compared to the dominant frequency-dependent time recommended by CPIA 655. Results for multiple test configurations, including stable and unstable configurations, were reviewed. Spontaneous stability was assessed using two processes: 1) characterization of the ratio of the peak response amplitudes to the excited chamber acoustic mode amplitudes and 2) characterization of the variability of the peak response

  2. Teaching and Learning in Chemical Product Engineering - an Evolving par of the Chemical Engineering Curriculum

    DEFF Research Database (Denmark)

    Vigild, Martin Etchells; Kiil, Søren; Wesselingh, Johannes

    2007-01-01

    and preparing a text book on the subject. [1] Chemical Product Engineering is solidly based on chemical technical and engineering knowledge. Furthermore, the subject naturally calls for a holistic approach to teaching and learning and introduces elements which target transferable and professional engineering......Over the last decade Chemical Product Engineering has evolved as part of the Chemical Engineering Curriculum at several universities in Europe and America. At the DTU Chemical Product Engineering was introduced in 2000. This presentation will report on the experiences gained from teaching classes...... skills. Such skills are important in Chemical Product Engineering when dealing with open-ended problems, creative problem solutions, operating in a team working environment and exercising project management. In our course we emphasise team activites, formative feed back to the students as well as helping...

  3. Numerical study on the combustion process of a biogas spark-ignition engine

    Directory of Open Access Journals (Sweden)

    Carrera José L.

    2013-01-01

    Full Text Available The fuel called biogas is obtained through anaerobic digestion of different types of organic waste, providing a way to tap the energy stored in organic matter. The use of this fuel is also attractive from the standpoint of global warming because its application does not register a net emission of carbon dioxide into the atmosphere. One possible use for this fuel is to feed the spark-ignition internal combustion engines. In the present, there is little information available about the process of combustion in internal combustion engines fueled by biogas. The combustion process of an internal combustion engine ignition powered by biogas is characterized in terms of the duration of combustion, i.e., depending on the time elapsed while the reactants (methane and oxygen are transformed into products (mainly carbon dioxide and water. This study numerically evaluates the way in which the geometrical parameters such as the compression ratio and operating parameters like engine speed, the excess air, the time of spark timing and carbon dioxide content of biogas affect the evolution of the combustion process. To carry out this study, a five factors and two levels experiment was designed and conducted, based on which, the most influential parameters were identified. Equations expressing the combustion characteristic parameters, as a function of the geometric and operation parameters of a spark ignited engines, are delivered as a result.

  4. An Experimental Investigation on the Combustion and Heat Release Characteristics of an Opposed-Piston Folded-Cranktrain Diesel Engine

    Directory of Open Access Journals (Sweden)

    Fukang Ma

    2015-06-01

    Full Text Available In opposed-piston folded-cranktrain diesel engines, the relative movement rules of opposed-pistons, combustion chamber components and injector position are different from those of conventional diesel engines. The combustion and heat release characteristics of an opposed-piston folded-cranktrain diesel engine under different operating conditions were investigated. Four phases: ignition delay, premixed combustion, diffusion combustion and after combustion are used to describe the heat release process of the engine. Load changing has a small effect on premixed combustion duration while it influences diffusion combustion duration significantly. The heat release process has more significant isochoric and isobaric combustion which differs from the conventional diesel engine situation, except at high exhaust pressure and temperature, due to its two-stroke and uniflow scavenging characteristics. Meanwhile, a relatively high-quality exhaust heat energy is produced in opposed-piston folded-cranktrain diesel engines.

  5. Study on Model Based Combustion Control of Diesel Engine with Multi Fuel Injection

    Science.gov (United States)

    Ikemura, R.; Yamasaki, Y.; Kaneko, S.

    2016-09-01

    A controller for model-based control of diesel engine with triple injection were developed with a combustion model. In the combustion model, an engine cycle is discretized into several representative points in order to improve calculation speed, while physical equations are employed to expand the versatility. The combustion model can predict in-cylinder pressure and temperature in these discrete points. Prediction accuracy of the combustion model was evaluated by comparison with experimental result. A controller was designed with the combustion model in order to calculate optimal fuel injection pattern for controlling in-cylinder pressure peak timing. The controller's performance was evaluated through simulation in which the combustion model was used as a plant model.

  6. Combustion and emission analysis of heavy-duty vehicle diesel engine

    Science.gov (United States)

    Sun, Zhixin; Wang, Xue; Wang, Xiancheng; Zhou, Jingkai

    2017-03-01

    Aiming at the research on combustion and emission characteristics of heavy-duty vehicle diesel engine, a bench test was carried out for PM and NOx emission for a certain type diesel engine under different speed and loads. Results shows that for this type of heavy-duty vehicle diesel engine, ignition delay is longer and the proportion of diffusion combustion increases under high speed of external characteristics conditions. Under the speed of 1400 r/min, ignition delay decreases with load increases, combustion duration shortened at first, then increases, the proportion of diffusion combustion increases. The ignition delay is longer and cylinder temperature is higher under lower speed external characteristics of diesel engine, the emissions of soot and NOx are heavier; with large load of external characteristics of diesel engine, the emissions of soot and NOx are heavy as well.

  7. FY2009 Annual Progress Report for Advanced Combustion Engine Research and Development

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2009-12-01

    Fiscal Year 2009 Annual Progress Report for the Advanced Combustion Engine Research and Development (R&D) subprogram. The Advanced Combustion Engine R&D subprogram supports the mission of the VTP program by removing the critical technical barriers to commercialization of advanced internal combustion engines (ICEs) for passenger and commercial vehicles that meet future Federal emissions regulations. Dramatically improving the efficiency of ICEs and enabling their introduction in conventional as well as hybrid electric vehicles is the most promising and cost-effective approach to increasing vehicle fuel economy over the next 30 years.

  8. In-cylinder Flow Characterisation of Heavy Duty Diesel Engines Using Combustion Image Velocimetry

    OpenAIRE

    Dembinski, Henrik

    2014-01-01

    In-cylinder flow in diesel engines has a large impact on combustion and emission formation. In this work, the flow is characterised with a new measurement method called combustion image velocimetry (CIV). This technique is used to explain how airflow introduced during induction affects soot emissions and interacts with injection pressures up to 2500 bar. The CIV measurements enable flow analysis during the combustion and post-oxidation phases. The flow velocities inside the cylinder of a heav...

  9. Optical investigations of combustion process in SI and CI engines fuelled with butanol blends

    Energy Technology Data Exchange (ETDEWEB)

    Marchitto, L.; Mazzei, A.; Merola, S.S.; Tornatore, C. [CNR Napoli, Naples (Italy). Istituto Motori; Valentino, G.

    2013-06-01

    The use of alternative fuels, as biodiesel and ethanol, for light duty engines to approach the target of low exhaust emissions without fuel economy and performance penalty has been widely investigated. Recently it is growing the interest in the butanol and bio-butanol as viable alternatives either single or blended with conventional based fuels. In this paper, butanol effects on combustion processes were investigated through conventional methods and optical diagnostics applied in the combustion chamber of a compression ignition engine and of a spark ignition engine. Blends of diesel and n-butanol were used in a common rail DI diesel engine running at different operating conditions. Fuel injection timing and oxygen at the intake were changed in a single cylinder compression ignition engine equipped with common rail multi-jets injection system. Spray combustion and pollutant formation were investigated though UV-visible digital imaging and natural emission spectroscopy. Flame emissions and spectroscopy were applied in an optically accessible cylinder of a port fuel-injection, spark-ignition engine with an external boosting device. The engine worked with a stoichiometric mixture at medium speed and boosting in wide open throttle condition. Normal and knocking combustion was tested. Experiments in both the engines demonstrated that butanol allowed to reduce carbonaceous compounds formation and soot emission and to decrease unpleasant effects related to the combustion process such as the fuel deposition burning. Moreover some emission bands of OH radicals could be used as feature of different phenomena related to the combustion process. (orig.)

  10. Investigation of Bio-Diesel Fueled Engines under Low-Temperature Combustion Strategies

    Energy Technology Data Exchange (ETDEWEB)

    Chia-fon F. Lee; Alan C. Hansen

    2010-09-30

    In accordance with meeting DOE technical targets this research was aimed at developing and optimizing new fuel injection technologies and strategies for the combustion of clean burning renewable fuels in diesel engines. In addition a simultaneous minimum 20% improvement in fuel economy was targeted with the aid of this novel advanced combustion system. Biodiesel and other renewable fuels have unique properties that can be leveraged to reduce emissions and increase engine efficiency. This research is an investigation into the combustion characteristics of biodiesel and its impacts on the performance of a Low Temperature Combustion (LTC) engine, which is a novel engine configuration that incorporates technologies and strategies for simultaneously reducing NOx and particulate emissions while increasing engine efficiency. Generating fundamental knowledge about the properties of biodiesel and blends with petroleum-derived diesel and their impact on in-cylinder fuel atomization and combustion processes was an important initial step to being able to optimize fuel injection strategies as well as introduce new technologies. With the benefit of this knowledge experiments were performed on both optical and metal LTC engines in which combustion and emissions could be observed and measured under realistic conditions. With the aid these experiments and detailed combustion models strategies were identified and applied in order to improve fuel economy and simultaneously reduce emissions.

  11. Spray and combustion visualization of bio-diesel in a direct injection diesel engine

    Directory of Open Access Journals (Sweden)

    Pan Jianfeng

    2013-01-01

    Full Text Available By using the self-developed dynamic visualization photographic setup, this article investigated some major factors affecting the spray and combustion process of diesel engine fueled by biodiesel. The experimental results show: With the increase of biodiesel percentage, fuel injection advances slightly, the ignition delay becomes shorter and the duration of combustion lengthens. Engine speed has little effect on the spray. However, the combustion rate is increased and the burning time becomes shorter with the increase of engine speed, although the duration of combustion in terms of crank angle increases. With the increase of needle opening pressure, both the spray cone angle and the spray penetration of biodiesel increases, the atomization of spray improves, the ignition delay and the duration of combustion becomes shorter, the peak pressure increases.

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

    Science.gov (United States)

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

    2016-03-01

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

  13. Transpiring Cooling of a Scram-Jet Engine Combustion Chamber

    Science.gov (United States)

    Choi, Sang H.; Scotti, Stephen J.; Song, Kyo D.; Ries,Heidi

    1997-01-01

    The peak cold-wall heating rate generated in a combustion chamber of a scram-jet engine can exceed 2000 Btu/sq ft sec (approx. 2344 W/sq cm). Therefore, a very effective heat dissipation mechanism is required to sustain such a high heating load. This research focused on the transpiration cooling mechanism that appears to be a promising approach to remove a large amount of heat from the engine wall. The transpiration cooling mechanism has two aspects. First, initial computations suggest that there is a reduction, as much as 75%, in the heat flux incident on the combustion chamber wall due to the transpirant modifying the combustor boundary layer. Secondly, the heat reaching the combustor wall is removed from the structure in a very effective manner by the transpirant. It is the second of these two mechanisms that is investigated experimentally in the subject paper. A transpiration cooling experiment using a radiant heating method, that provided a heat flux as high as 200 Btu/sq ft sec ( approx. 234 W/sq cm) on the surface of a specimen, was performed. The experiment utilized an arc-lamp facility (60-kW radiant power output) to provide a uniform heat flux to a test specimen. For safety reasons, helium gas was used as the transpirant in the experiments. The specimens were 1.9-cm diameter sintered, powdered-stainless-steel tubes of various porosities and a 2.54cm square tube with perforated multi-layered walls. A 15-cm portion of each specimen was heated. The cooling effectivenes and efficiencies by transpiration for each specimen were obtained using the experimental results. During the testing, various test specimens displayed a choking phenomenon in which the transpirant flow was limited as the heat flux was increased. The paper includes a preliminary analysis of the transpiration cooling mechanism and a scaling conversion study that translates the results from helium tests into the case when a hydrogen medium is used.

  14. Application of the Advanced Distillation Curve Method to Fuels for Advanced Combustion Engine Gasolines

    KAUST Repository

    Burger, Jessica L.

    2015-07-16

    © This article not subject to U.S. Copyright. Published 2015 by the American Chemical Society. Incremental but fundamental changes are currently being made to fuel composition and combustion strategies to diversify energy feedstocks, decrease pollution, and increase engine efficiency. The increase in parameter space (by having many variables in play simultaneously) makes it difficult at best to propose strategic changes to engine and fuel design by use of conventional build-and-test methodology. To make changes in the most time- and cost-effective manner, it is imperative that new computational tools and surrogate fuels are developed. Currently, sets of fuels are being characterized by industry groups, such as the Coordinating Research Council (CRC) and other entities, so that researchers in different laboratories have access to fuels with consistent properties. In this work, six gasolines (FACE A, C, F, G, I, and J) are characterized by the advanced distillation curve (ADC) method to determine the composition and enthalpy of combustion in various distillate volume fractions. Tracking the composition and enthalpy of distillate fractions provides valuable information for determining structure property relationships, and moreover, it provides the basis for the development of equations of state that can describe the thermodynamic properties of these complex mixtures and lead to development of surrogate fuels composed of major hydrocarbon classes found in target fuels.

  15. Green chemical engineering aspects of reactive distillation.

    Science.gov (United States)

    Malone, Michael F; Huss, Robert S; Doherty, Michael F

    2003-12-01

    Reactive or catalytic distillation technology combines chemical synthesis steps with separations by distillation. This combination can lead to intensified, high-efficiency process systems with significant green engineering attributes. New applications and understanding have prompted growth in the use of reactive distillation for a variety of chemical syntheses, especially esterifications and etherifications involving oxygenated hydrocarbons. We describe several applications and the potential and tradeoffs for reactive distillation technology in the context of green engineering principles.

  16. Research status of key techniques for shock-induced combustion ramjet(shcramjet) engine

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    As one of the most promising propulsion systems in the future,shock-induced combustion ramjet engine can remedy the disadvantages in the integrated design of scramjet engine and airframe.It can shorten the length of the combustor,lighten the structure weight of the engine and keep better performance in a broad range of flight Mach number.The elementary principle of shock-induced combustion ramjet engine is introduced.The key technologies of this kind of propulsion system are described,while their research status is presented in detail.Suggestion on the development of shcramjet engine in China is put forward.

  17. An experiment study of homogeneous charge compression ignition combustion and emission in a gasoline engine

    Directory of Open Access Journals (Sweden)

    Zhang Jianyong

    2014-01-01

    Full Text Available Homogenous charge compression ignition (HCCI technology has exhibited high potential to reduce fuel consumption and NOx emissions over normal spark ignition engines significantly. Optimized kinetic process (OKP technology is implemented to realize HCCI combustion in a port fuel injection gasoline engine. The combustion and emission characteristics are investigated with variation of intake air temperature, exhaust gas recirculation (EGR rate and intake air pressure. The results show that intake air temperature has great influence on HCCI combustion characteristic. Increased intake air temperature results in advance combustion phase, shorten combustion duration, and lower indicated mean effective pressure (IMEP. Increased EGR rate retards combustion start phase and prolongs combustion duration, while maximum pressure rising rate and NOx emission are reduced with increase of EGR rate. In the condition with constant fuel flow quantity, increased air pressure leads to retarded combustion phase and lower pressure rising rate, which will reduce the engine knocking tendency. In the condition with constant air fuel ratio condition, fuel injection quantity increases as intake air pressure increases, which lead to high heat release rate and high emission level. The optimal intake air temperature varies in different operating area, which can be tuned from ambient temperature to 220℃ by heat management system. The combination of EGR and air boost technology could expand operating area of HCCI engine, which improve indicated mean effective pressure from maximum 510kPa to 720kPa.

  18. The role of chemical engineering in pharmaceutical chemical process development.

    Science.gov (United States)

    Landau, R N; Blacklock, T J; Girgis, M J; Tedesco, A

    1998-11-01

    The task of chemical process development in the pharmaceutical industry has grown into a multidisciplinary endeavor requiring years to complete. Increased competition in the pharmaceutical Additionally, the ever-tightening regulatory environment further compromises the business objective (ultimately, profits). This has required careful analysis of the activities within development. This work discusses the results of this analysis, which shows how a balance between minimal resource utilization and phased development achievements can be reached. The cycle of development, from inception to completion, is examined. Special emphasis is placed upon the role of chemical engineering and its appropriate deployment. Simple examples of the synergies that are possible between chemistry and chemical engineering are also given.

  19. Combustion Analysis and Knock Detection in Single Cylinder DI-Diesel Engine Using Vibration Signature Analysis

    OpenAIRE

    Y.V.V.SatyanarayanaMurthy

    2011-01-01

    The purpose of this paper is to detect the “knock” in Diesel engines which deteriorate the engine performance adversely. The methodology introduced in the present work suggests a newly developed approach towards analyzing the vibration analysis of diesel engines. The method is based on fundamental relationship between the engine vibration pattern and the relative characteristics of the combustion process in each or different cylinders. Knock in diesel engine is detected by measuring the vibra...

  20. Internal combustion engines performance simulation; Simulacao de desempenho de motores de combustao interna

    Energy Technology Data Exchange (ETDEWEB)

    Monteiro, Jose F.C.; Barbosa, Joao R. [Centro Tecnico Aeroespacial, Sao Jose dos Campos, SP (Brazil). Inst. Tecnologico de Aeronautica. Dept. de Energia]. E-mail: monteiro@asap.iae.cta.br; barbosa@mec.ita.cta.br

    2000-07-01

    A study of numerical methods for the simulation of internal combustion engines is presented. Functional blocks, representing each component of the engine, can be combined to simulate the engine. A model was selected for each component. The engine simulation is carried out connecting the functional blocks. The inviscid conservation equations coupled with loss models where solved using a C++ computer program. Engine performance simulation is shown and results compared with published data. (author)

  1. The railplug: A new ignitor for internal combustion engines

    Energy Technology Data Exchange (ETDEWEB)

    Faidley, R.W.; Darden, M.H.; Weldon, W.F.

    1995-01-01

    A miniaturized railgun, termed the {open_quotes}railplug,{close_quotes} has been developed for use as an ignitor of combustible mixtures in engines. The device drives a plasma armature in a multishot mode with the aim of creating a line-source for ignition rather than the point source provided by traditional spark plugs. Railplugs have been fabricated in both parallel rail and co-axial rail geometries. The railplug differs from most plasma armature railguns in two striking ways: (1) no fuse or pellet is used to initially establish the plasma (the armature is simply the arc created by a high-voltage pulse), and (2) it operates over a range of elevated pressures (up to 500 psi). Consequently, the railplug power supply must provide a high voltage spike to breakdown the gap between the rails followed by a sustaining voltage that supplies current to drive the arc down the rails. Conceptually, this is the equivalent of combining the electrostatic problem of a sparkplug with the electrodynamic one of a railgun. Two power supply options that do this are outlined, as well as details of railplug geometries. Successes to date have demonstrated the firing of plugs for over 10{sup 4} shots at delivered arc energies of 1 J per shot. Rep rates have been demonstrated up to 50 Hz.

  2. Ionic liquids in chemical engineering.

    Science.gov (United States)

    Werner, Sebastian; Haumann, Marco; Wasserscheid, Peter

    2010-01-01

    The development of engineering applications with ionic liquids stretches back to the mid-1990s when the first examples of continuous catalytic processes using ionic liquids and the first studies of ionic liquid-based extractions were published. Ever since, the use of ionic liquids has seen tremendous progress in many fields of chemistry and engineering, and the first commercial applications have been reported. The main driver for ionic liquid engineering applications is to make practical use of their unique property profiles, which are the result of a complex interplay of coulombic, hydrogen bonding and van der Waals interactions. Remarkably, many ionic liquid properties can be tuned in a wide range by structural modifications at their cation and anion. This review highlights specific examples of ionic liquid applications in catalysis and in separation technologies. Additionally, the application of ionic liquids as working fluids in process machines is introduced.

  3. PARAMETER MATCHING OF INTERNAL COMBUSTION ENGINE AND ELECTROMECHANICAL POWER TRAIN OF WHEEL TRACTOR

    Directory of Open Access Journals (Sweden)

    A. Kliuchnikov

    2012-01-01

    Full Text Available The paper considers stepless electromechanical power train of a wheel tractor. Methodology for parameter matching of electromechanical transmission and internal combustion engine for their optimum performance as part of a power wheel tractor unit. 

  4. Development on a dynamic pressure test system of internal combustion engines

    Science.gov (United States)

    Yuan, Dongmei; Zou, Xihong; Xu, Yun

    2006-11-01

    The performance of a piston internal-combustion engines is reflected by indicator diagram and indicator parameters. It is of great significance to evaluate performance, inspect quality, redesign and maintain internal-combustion engine by computing parameter and analyzing combustion according to tested indicator diagram. Aimed at two-stroke piston engines, a dynamic pressure test system of internal-combustion engines is developed with high speed acquisition devices, angle signal generators and pulse shapers. After a further research on the measurement of dynamic top dead center (TDC), the computer algorithm based on the p-ψ indicator diagram of TDC and the average indicator pressure is putted forward. With the application of the multithreading technique, dynamic link library technique and multi-document template technique, a testing software, which is credible and multi-purpose, is programmed. The experiment indicates that the indicator diagram and indicator parameters can be under accurate measurement with the testing system.

  5. Influences of Catalytic Combustion on the Ignition Timing and Emissions of HCCI Engines

    Institute of Scientific and Technical Information of China (English)

    ZENG Wen; XIE Mao-zhao

    2008-01-01

    The combustion processes of homogeneous charge compression ignition (HCCI) engines whose piston surfaces have been coated with catalyst (rhodium or platinum) were numerically investigated. A single-zone model and a multi-zone model were developed. The effects of catalytic combustion on the ignition timing of the HCCI engine were analyzed through the single-zone model. The results showed that the ignition timing of the HCCI engine was advanced by the catalysis. The effects of catalytic combustion on HC, CO and NOx emissions of the HCCI engine were analyzed through the multi-zone model. The results showed that the emissions of HC and CO (using platinum (Pt) as catalyst) were decreased, while the emissions of NOx were elevated by catalytic combustion. Compared with catalyst Pt, the HC emissions were lower with catalyst rhodium(Rh) on the piston surface, but the emissions of NOx and CO were higher.

  6. Knock characteristics of dual-fuel combustion in diesel engines using natural gas as primary fuel

    Indian Academy of Sciences (India)

    O M I Nwafor

    2002-06-01

    This paper investigates the combustion knock characteristics of diesel engines running on natural gas using pilot injection as means of initiating combustion. The diesel engines knock under normal operating conditions but the knock referred to in this paper is an objectionable one. In the dual-fuel combustion process we have the ignition stage followed by the combustion stage. There are three types of knock: diesel knock, spark knock and knock due to secondary ignition delay of the primary fuel (erratic knock). Several factors have been noted to feature in defining knock characteristics of dual-fuel engines that include ignition delay, pilot quantity, engine load and speed, turbulence and gas flow rate.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2003-07-01

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

  8. Functional Analysis for Chemical Engineers.

    Science.gov (United States)

    Ramkrishna, D.

    1979-01-01

    Described is a graduate level engineering course on functional analysis offered at Purdue University. The course restricts itself to linear problems, specifically analysis of linear operators on vector spaces. Key applications in the course demonstrating the utility of abstract formulations are presented. (BT)

  9. Experimental investigation of CAI combustion in a two-stroke poppet valve DI engine

    OpenAIRE

    Zhang, Yan

    2015-01-01

    This thesis was submitted for the award of Doctor of Philosophy and was awarded by Brunel University London Due to their ability to simultaneously reduce fuel consumption and NOx emissions, Controlled Auto Ignition (CAI) and HCCI combustion processes have been extensively researched over the last decade and adopted on prototype gasoline engines. These combustion processes were initially achieved on conventional two-stroke ported gasoline engines, but there have been significantly fewer stu...

  10. FY2010 Annual Progress Report for Advanced Combustion Engine Research and Development

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Gurpreet [Office of Energy Efficiency and Renewable Energy (EERE), Washington, DC (United States)

    2010-12-01

    The Advanced Combustion Engine R&D subprogram supports the mission of the Vehicle Technologies Program by removing the critical technical barriers to commercialization of advanced internal combustion engines (ICEs) for passenger and commercial vehicles that meet future Federal emissions regulations. Dramatically improving the efficiency of ICEs and enabling their introduction in conventional as well as hybrid electric vehicles is the most promising and cost-effective approach to increasing vehicle fuel economy over the next 30 years.

  11. Problems of providing completeness of the methane-containing block-jet combustion in a rocket-ramjet engine's combustion chamber

    Science.gov (United States)

    Timoshenko, Valeriy I.; Belotserkovets, Igor S.; Gusinin, Vjacheslav P.

    2009-11-01

    Some problems of methane-containing hydrocarbon fuel combustion are discussed. It seems that reduction of methane burnout zone length is one from main problems of designing new type engine. It is very important at the creation of combustion chambers of a rocket-ramjet engine for prospective space shuttle launch vehicles.

  12. Combustion flame-plasma hybrid reactor systems, and chemical reactant sources

    Science.gov (United States)

    Kong, Peter C

    2013-11-26

    Combustion flame-plasma hybrid reactor systems, chemical reactant sources, and related methods are disclosed. In one embodiment, a combustion flame-plasma hybrid reactor system comprising a reaction chamber, a combustion torch positioned to direct a flame into the reaction chamber, and one or more reactant feed assemblies configured to electrically energize at least one electrically conductive solid reactant structure to form a plasma and feed each electrically conductive solid reactant structure into the plasma to form at least one product is disclosed. In an additional embodiment, a chemical reactant source for a combustion flame-plasma hybrid reactor comprising an elongated electrically conductive reactant structure consisting essentially of at least one chemical reactant is disclosed. In further embodiments, methods of forming a chemical reactant source and methods of chemically converting at least one reactant into at least one product are disclosed.

  13. Dual-Fuel Combustion for Future Clean and Efficient Compression Ignition Engines

    Directory of Open Access Journals (Sweden)

    Jesús Benajes

    2016-12-01

    Full Text Available Stringent emissions limits introduced for internal combustion engines impose a major challenge for the research community. The technological solution adopted by the manufactures of diesel engines to meet the NOx and particle matter values imposed in the EURO VI regulation relies on using selective catalytic reduction and particulate filter systems, which increases the complexity and cost of the engine. Alternatively, several new combustion modes aimed at avoiding the formation of these two pollutants by promoting low temperature combustion reactions, are the focus of study nowadays. Among these new concepts, the dual-fuel combustion mode known as reactivity controlled compression ignition (RCCI seems more promising because it allows better control of the combustion process by means of modulating the fuel reactivity depending on the engine operating conditions. The present experimental work explores the potential of different strategies for reducing the energy losses with RCCI in a single-cylinder research engine, with the final goal of providing the guidelines to define an efficient dual-fuel combustion system. The results demonstrate that the engine settings combination, piston geometry modification, and fuel properties variation are good methods to increase the RCCI efficiency while maintaining ultra-low NOx and soot emissions for a wide range of operating conditions.

  14. Investigation of Chemical Kinetics on Soot Formation Event of n-Heptane Spray Combustion

    DEFF Research Database (Denmark)

    Pang, Kar Mun; Jangi, Mehdi; Bai, Xue-Song

    2014-01-01

    In this reported work, 2-dimsensional computational fluid dynamics studies of n-heptane combustion and soot formation processes in the Sandia constant-volume vessel are carried out. The key interest here is to elucidate how the chemical kinetics affects the combustion and soot formation events. N...

  15. Effects of oxygen enriched combustion on pollution and performance characteristics of a diesel engine

    Directory of Open Access Journals (Sweden)

    P. Baskar

    2016-03-01

    Full Text Available Oxygen enriched combustion is one of the attractive combustion technologies to control pollution and improve combustion in diesel engines. An experimental test was conducted on a single cylinder direct injection diesel engine to study the impact of oxygen enrichment on pollution and performance parameters by increasing the oxygen concentration of intake air from 21 to 27% by volume. The tests results show that the combustion process was improved as there is an increase in thermal efficiency of 4 to 8 percent and decrease in brake specific fuel consumption of 5 to 12 percent. There is also a substantial decrease in unburned hydro carbon, carbon mono-oxide and smoke density levels to the maximum of 40, 55 and 60 percent respectively. However, there is a considerable increase in nitrogen oxide emissions due to increased combustion temperature and extra oxygen available which needs to be addressed.

  16. An assessment of combustion products of spark ignition engines supplied by ethanol - gasoline blends

    Science.gov (United States)

    Uzuneanu, K.; Golgotiu, E.

    2016-08-01

    The causes of environmental pollution by internal combustion engines arise from the use of fuels containing bounded carbon, from the fact that combustion takes place on a cyclic basis and at high temperature. The first and the last causes are directly related to the fuel and therefore there is in principle a possibility to reduce pollution by acting upon the fuel used. The present paper deals with the comparison of the level of combustion products of a spark ignition engine supplied by gasoline and by a mixture of 10 % ethanol - 90% gasoline.

  17. A Progress Review on Soot Experiments and Modeling in the Engine Combustion Network (ECN)

    KAUST Repository

    Skeen, Scott A.

    2016-04-05

    The 4th Workshop of the Engine Combustion Network (ECN) was held September 5-6, 2015 in Kyoto, Japan. This manuscript presents a summary of the progress in experiments and modeling among ECN contributors leading to a better understanding of soot formation under the ECN “Spray A” configuration and some parametric variants. Relevant published and unpublished work from prior ECN workshops is reviewed. Experiments measuring soot particle size and morphology, soot volume fraction (fv), and transient soot mass have been conducted at various international institutions providing target data for improvements to computational models. Multiple modeling contributions using both the Reynolds Averaged Navier-Stokes (RANS) Equations approach and the Large-Eddy Simulation (LES) approach have been submitted. Among these, various chemical mechanisms, soot models, and turbulence-chemistry interaction (TCI) methodologies have been considered.

  18. Mechanism and optimization of fuel injection parameters on combustion noise of DI diesel engine

    Institute of Scientific and Technical Information of China (English)

    张庆辉; 郝志勇; 郑旭; 杨文英; 毛杰

    2016-01-01

    Combustion noise takes large proportion in diesel engine noise and the studies of its influence factors play an important role in noise reduction. Engine noise and cylinder pressure measurement experiments were carried out. And the improved attenuation curves were obtained, by which the engine noise was predicted. The effect of fuel injection parameters in combustion noise was investigated during the combustion process. At last, the method combining single variable optimization and multivariate combination was introduced to online optimize the combustion noise. The results show that injection parameters can affect the cylinder pressure rise rate and heat release rate, and consequently affect the cylinder pressure load and pressure oscillation to influence the combustion noise. Among these parameters, main injection advance angle has the greatest influence on the combustion noise, while the pilot injection interval time takes the second place, and the pilot injection quantity is of minimal impact. After the optimal design of the combustion noise, the average sound pressure level of the engine is distinctly reduced by 1.0 dB(A) generally. Meanwhile, the power, emission and economy performances are ensured.

  19. Research on EHN additive on the diesel engine combustion characteristics in plateau environment

    Science.gov (United States)

    Sun, Zhixin; Li, Ruoting; Wang, Xiancheng; Hu, Chuan

    2017-03-01

    Aiming at the combustion deterioration problem of diesel engine in plateau environment, a bench test was carried out for the effects of EHN additive on combustion characteristics of the diesel engine with intake pressure of 0.68 kPa. Test results showed that with the full load working condition of 1 400 r/min: Cylinder pressure and pressure uprising rate decreased with EHN additive added in, mechanical load on the engine could be relieved; peak value of the heat release rate decreased and its occurrence advanced, ignition delay and combustion duration were shortened; cylinder temperature and exhaust gas temperature declined, thermal load on the engine could be relieved, output torque increased while specific oil consumption decreased, and effective thermal efficiency of diesel engine increased.

  20. Acoustic measurements for the combustion diagnosis of diesel engines fuelled with biodiesels

    Science.gov (United States)

    Zhen, Dong; Wang, Tie; Gu, Fengshou; Tesfa, Belachew; Ball, Andrew

    2013-05-01

    In this paper, an experimental investigation was carried out on the combustion process of a compression ignition (CI) engine running with biodiesel blends under steady state operating conditions. The effects of biodiesel on the combustion process and engine dynamics were analysed for non-intrusive combustion diagnosis based on a four-cylinder, four-stroke, direct injection and turbocharged diesel engine. The signals of vibration, acoustic and in-cylinder pressure were measured simultaneously to find their inter-connection for diagnostic feature extraction. It was found that the sound energy level increases with the increase of engine load and speed, and the sound characteristics are closely correlated with the variation of in-cylinder pressure and combustion process. The continuous wavelet transform (CWT) was employed to analyse the non-stationary nature of engine noise in a higher frequency range. Before the wavelet analysis, time synchronous average (TSA) was used to enhance the signal-to-noise ratio (SNR) of the acoustic signal by suppressing the components which are asynchronous. Based on the root mean square (RMS) values of CWT coefficients, the effects of biodiesel fractions and operating conditions (speed and load) on combustion process and engine dynamics were investigated. The result leads to the potential of airborne acoustic measurements and analysis for engine condition monitoring and fuel quality evaluation.

  1. An insight into chemical kinetics and turbulence-chemistry interaction modeling in flameless combustion

    Directory of Open Access Journals (Sweden)

    Amir Azimi, Javad Aminian

    2015-01-01

    Full Text Available Computational Fluid Dynamics (CFD study of flameless combustion condition is carried out by solving the Reynolds-Averaged Navier-Stokes (RANS equations in the open-source CFD package of OpenFOAM 2.1.0. Particular attention is devoted to the comparison of three global and detailed chemical mechanisms using the Partially Stirred Reactor (PaSR combustion model for the turbulence-chemistry interaction treatment. The OpenFOAM simulations are assessed against previously published CFD results using the Eddy Dissipation Concept (EDC combustion model as well as the experimental data available in the literature. Results show that global chemical mechanisms provide acceptable predictions of temperature and major species fields in flameless mode with much lower computational costs comparing with the detailed chemical mechanisms. However, incorporation of detailed chemical mechanisms with proper combustion models is crucial to account for finite-rate chemistry effects and accurately predict net production of minor species.

  2. Modeling of Transient Heat Flux in Spark Ignition Engine During Combustion and Comparisons with Experiment

    Directory of Open Access Journals (Sweden)

    T. F. Yusaf

    2005-01-01

    Full Text Available A quasi-one dimensional engine cycle simulation program was developed to predict the transient heat flux during combustion in a spark ignition engine. A two-zone heat release model was utilized to model the combustion process inside the combustion chamber. The fuel, air and burned gas properties throughout the engine cycle were calculated using variable specific heats. The transient heat flux inside the combustion chamber due to the change in the in-cylinder gas temperature and pressure during combustion was determined using the Woschni heat transfer model. The program was written in MATLAB together with the Graphical User Interface (GUI. Numerical results were compared with the experimental measurements and good agreement was obtained. Four thermocouples were used and positioned equi-spaced at 5mm intervals along a ray from the spark plug location on the engine head. These thermocouples were able to capture the heat flux release by the burned gas to the wall during the combustion process including the cycle-to-cycle variations. Pressure sensor was installed at the engine head to capture the pressure change throughout the cycle.

  3. The scaling of performance and losses in miniature internal combustion engines

    Science.gov (United States)

    Menon, Shyam Kumar

    Miniature glow ignition internal combustion (IC) piston engines are an off--the--shelf technology that could dramatically increase the endurance of miniature electric power supplies and the range and endurance of small unmanned air vehicles provided their overall thermodynamic efficiencies can be increased to 15% or better. This thesis presents the first comprehensive analysis of small (engine performance. A unique dynamometer system is developed that is capable of making reliable measurements of engine performance and losses in these small engines. Methodologies are also developed for measuring volumetric, heat transfer, exhaust, mechanical, and combustion losses. These instruments and techniques are used to investigate the performance of seven single-cylinder, two-stroke, glow fueled engines ranging in size from 15 to 450 g (0.16 to 7.5 cm3 displacement). Scaling rules for power output, overall efficiency, and normalized power are developed from the data. These will be useful to developers of micro-air vehicles and miniature power systems. The data show that the minimum length scale of a thermodynamically viable piston engine based on present technology is approximately 3 mm. Incomplete combustion is the most important challenge as it accounts for 60-70% of total energy losses. Combustion losses are followed in order of importance by heat transfer, sensible enthalpy, and friction. A net heat release analysis based on in-cylinder pressure measurements suggest that a two--stage combustion process occurs at low engine speeds and equivalence ratios close to 1. Different theories based on burning mode and reaction kinetics are proposed to explain the observed results. High speed imaging of the combustion chamber suggests that a turbulent premixed flame with its origin in the vicinity of the glow plug is the primary driver of combustion. Placing miniature IC engines on a turbulent combustion regime diagram shows that they operate in the 'flamelet in eddy' regime

  4. Simulation and experiment for oxygen-enriched combustion engine using liquid oxygen to solidify CO2

    Science.gov (United States)

    Liu, Yongfeng; Jia, Xiaoshe; Pei, Pucheng; Lu, Yong; Yi, Li; Shi, Yan

    2016-01-01

    For capturing and recycling of CO2 in the internal combustion engine, Rankle cycle engine can reduce the exhaust pollutants effectively under the condition of ensuring the engine thermal efficiency by using the techniques of spraying water in the cylinder and optimizing the ignition advance angle. However, due to the water spray nozzle need to be installed on the cylinder, which increases the cylinder head design difficulty and makes the combustion conditions become more complicated. In this paper, a new method is presented to carry out the closing inlet and exhaust system for internal combustion engines. The proposed new method uses liquid oxygen to solidify part of cooled CO2 from exhaust system into dry ice and the liquid oxygen turns into gas oxygen which is sent to inlet system. The other part of CO2 is sent to inlet system and mixed with oxygen, which can reduce the oxygen-enriched combustion detonation tendency and make combustion stable. Computing grid of the IP52FMI single-cylinder four-stroke gasoline-engine is established according to the actual shape of the combustion chamber using KIVA-3V program. The effects of exhaust gas recirculation (EGR) rate are analyzed on the temperatures, the pressures and the instantaneous heat release rates when the EGR rate is more than 8%. The possibility of enclosing intake and exhaust system for engine is verified. The carbon dioxide trapping device is designed and the IP52FMI engine is transformed and the CO2 capture experiment is carried out. The experimental results show that when the EGR rate is 36% for the optimum EGR rate. When the liquid oxygen of 35.80-437.40 g is imported into the device and last 1-20 min, respectively, 21.50-701.30 g dry ice is obtained. This research proposes a new design method which can capture CO2 for vehicular internal combustion engine.

  5. Modeling and Simulation of a Free-Piston Engine with Electrical Generator Using HCCI Combustion

    Science.gov (United States)

    Alrbai, Mohammad

    Free-piston engines have the potential to challenge the conventional crankshaft engines by their design simplicity and higher operational efficiency. Many studies have been performed to overcome the limitations of the free-piston devices especially the stability and control issues. The investigations within the presented dissertation aim to satisfy many objectives by employing the approach of chemical kinetics to present the combustion process in the free-piston engine. This approach in addition to its advanced accuracy over the empirical methods, it has many other features like the ability to analyze the engine emissions. The effect of the heat release rate (HRR) on the engine performance is considered as the main objective. Understanding the relation between the HRR and the piston dynamics helps in enhancing the system efficiency and identifying the parameters that affect the overall performance. The dissertation covers some other objectives that belongs to the combustion phasing. Exhaust gas recirculation (EGR), equivalence ratio and the intake temperature represent the main combustion parameters, which have been discussed in this dissertation. To obtain the stability in system performance, the model requires a proper controller to simulate the operation and manage the different system parameters; for this purpose, different controlling techniques have been employed. In addition, the dissertation considers some other topics like engine emissions, fuels and fuels mechanisms. The model of the study describes the processes within a single cylinder, two stroke engine, which includes springs to support higher frequencies, reduce cyclic variations and sustain the engine compression ratio. An electrical generator presents the engine load; the generator supports different load profiles and play the key role in controlling the system. The 1st law of thermodynamics and Newton's 2nd law are applied to couple the piston dynamics with the engine thermodynamics. The model

  6. Lectures on combustion theory

    Energy Technology Data Exchange (ETDEWEB)

    Burstein, S.Z.; Lax, P.D.; Sod, G.A. (eds.)

    1978-09-01

    Eleven lectures are presented on mathematical aspects of combustion: fluid dynamics, deflagrations and detonations, chemical kinetics, gas flows, combustion instability, flame spread above solids, spark ignition engines, burning rate of coal particles and hydrocarbon oxidation. Separate abstracts were prepared for three of the lectures. (DLC)

  7. Genetic Algorithm-Based Design Optimization of Electromagnetic Valve Actuators in Combustion Engines

    OpenAIRE

    Seung Hwan Lee; Hwa Cho Yi; Kyuyoung Han; Jin Ho Kim

    2015-01-01

    In this research, the design of a new electromagnetic engine valve in the limited space of combustion engine is optimized by multidisciplinary simulation using MATLAB and Maxwell. An electromagnetic engine valve actuator using a permanent magnet is a new actuator concept for overcoming the inherent drawbacks of the conventional solenoid-driven electromagnetic engine valve actuator, such as high power consumption and so on. This study aims to maximize the vibration frequency of the armature to...

  8. Thermodynamic efficiency of present types of internal combustion engines for aircraft

    Science.gov (United States)

    Lucke, Charles E

    1917-01-01

    Report presents requirements of internal combustion engines suitable for aircraft. Topics include: (1) service requirements for aeronautic engines - power versus weight, reliability, and adaptability factors, (2) general characteristics of present aero engines, (3) aero engine processes and functions of parts versus power-weight ratio, reliability, and adaptability factors, and (4) general arrangement, form, proportions, and materials of aero parts - power-weight ratio, reliability, and adaptability.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  10. Numerical prediction of the chemical composition of gas products at biomass combustion and co-combustion in a domestic boiler

    Directory of Open Access Journals (Sweden)

    Radomiak Henryk

    2017-01-01

    Full Text Available In recent years the numerical modelling of biomass combustion has been successfully applied to determine the combustion mechanism and predict its products. In this study the influence of the addition of waste glycerin in biomass wood pellets on the chemical composition of exhaust gases has been investigated. The pellets have been prepared from spruceand pine wood sawdust without and with addition of waste glycerin. The waste glycerol is a undesirable by-product of biodiesel transesterification at oil manufacturing. The produced pellets were being burned in the 10 kW domestic boiler adapted to wood pellets combustion. The possibilities of pollutants generation (CO2, CO, NOx SOx and compounds containing chlorine in the exhaust gases coming from the boiler were numerically calculated using the latest version of CHEMKIN-PRO software, introduced by the American company Reaction Design. The results of the calculations correspond to the data obtained on a real object, in particular: combustion temperature, gas pressure, residence time of fuel in the burner, air flow, fuel consumption, as well as elementary composition of fuel supplied into the boiler. The proposed method of predicting the chemical composition of exhaust gases allows proper control of the combustion process and can be considered as an important step in reducing the pollutants (lower emission of NOx, SOx and CO2 neutral and thus to contribute to the improvement of the environmental quality. In addition, knowledge of the amounts of Clbased compounds produced in combustion process (under given conditions, can serve as an important hint in terms of corrosion prevention of boiler- and chimney steels.

  11. Engineering microbes for efficient production of chemicals

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Wei; Dole, Sudhanshu; Grabar, Tammy; Collard, Andrew Christopher; Pero, Janice G; Yocum, R Rogers

    2015-04-28

    This present invention relates to production of chemicals from microorganisms that have been genetically engineered and metabolically evolved. Improvements in chemical production have been established, and particular mutations that lead to those improvements have been identified. Specific examples are given in the identification of mutations that occurred during the metabolic evolution of a bacterial strain genetically engineered to produce succinic acid. This present invention also provides a method for evaluating the industrial applicability of mutations that were selected during the metabolic evolution for increased succinic acid production. This present invention further provides microorganisms engineered to have mutations that are selected during metabolic evolution and contribute to improved production of succinic acid, other organic acids and other chemicals of commercial interest.

  12. Ab initio Quantum Chemical Reaction Kinetics: Recent Applications in Combustion Chemistry (Briefing Charts)

    Science.gov (United States)

    2015-06-28

    ghanshyam.vaghjiani@us.af.mil Ab initio Quantum Chemical Reaction Kinetics: Recent Applications in Combustion Chemistry Ghanshyam L. Vaghjiani* DISTRIBUTION A...Charts 3. DATES COVERED (From - To) June 2015-June 2015 4. TITLE AND SUBTITLE AB INITIO QUANTUM CHEMICAL REACTION KINETICS: RECENT APPLICATIONS IN...COMBUSTION CHEMISTRY (Briefing Charts) 5a. CONTRACT NUMBER In-House 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Ghanshyam L

  13. Chemical Engineering Education - Current and Future Trends

    DEFF Research Database (Denmark)

    Gani, Rafiqul

    The chemical industry today is changed from the chemical industry of twenty-five years ago. Clear evidence of this change comes from the jobs taken by graduating chemical professionals in North America, Europe, and some of the Asian countries. Twenty-five years ago, eighty percent of these gradua......The chemical industry today is changed from the chemical industry of twenty-five years ago. Clear evidence of this change comes from the jobs taken by graduating chemical professionals in North America, Europe, and some of the Asian countries. Twenty-five years ago, eighty percent...... should be measured on their level of knowledge and the understanding they develop, rather than the amount of time they spend with the tutors. According to the Bologna Process, the first and the second cycle degrees should have different orientations and various profiles in order to accommodate...... completion of the first cycle, students can continue their study with a second cycle program of chemical engineering with 90-120 credits for a further 18-24 months. For the first and second cycles, the EFCE recommend a set of programme outcomes (knowledge and understanding, engineering analysis, engineering...

  14. Numerical simulation and validation of SI-CAI hybrid combustion in a CAI/HCCI gasoline engine

    Science.gov (United States)

    Wang, Xinyan; Xie, Hui; Xie, Liyan; Zhang, Lianfang; Li, Le; Chen, Tao; Zhao, Hua

    2013-02-01

    SI-CAI hybrid combustion, also known as spark-assisted compression ignition (SACI), is a promising concept to extend the operating range of CAI (Controlled Auto-Ignition) and achieve the smooth transition between spark ignition (SI) and CAI in the gasoline engine. In this study, a SI-CAI hybrid combustion model (HCM) has been constructed on the basis of the 3-Zones Extended Coherent Flame Model (ECFM3Z). An ignition model is included to initiate the ECFM3Z calculation and induce the flame propagation. In order to precisely depict the subsequent auto-ignition process of the unburned fuel and air mixture independently after the initiation of flame propagation, the tabulated chemistry concept is adopted to describe the auto-ignition chemistry. The methodology for extracting tabulated parameters from the chemical kinetics calculations is developed so that both cool flame reactions and main auto-ignition combustion can be well captured under a wider range of thermodynamic conditions. The SI-CAI hybrid combustion model (HCM) is then applied in the three-dimensional computational fluid dynamics (3-D CFD) engine simulation. The simulation results are compared with the experimental data obtained from a single cylinder VVA engine. The detailed analysis of the simulations demonstrates that the SI-CAI hybrid combustion process is characterised with the early flame propagation and subsequent multi-site auto-ignition around the main flame front, which is consistent with the optical results reported by other researchers. Besides, the systematic study of the in-cylinder condition reveals the influence mechanism of the early flame propagation on the subsequent auto-ignition.

  15. A simple strategy to establish preliminary engine cylinder geometry for optimum combustion

    Energy Technology Data Exchange (ETDEWEB)

    Harish Kumar, R. [Sri Siddhartha Inst. of Technology, Karnataka (India); Antony, A.J. [Sahyadri Inst. of Technology, Mangalore, Karnataka (India)

    2009-07-01

    The design of modern spark ignition engines presents a challenge for automotive engineers in terms of striking the right combination of engine operating parameters and geometry. Most modern spark ignition engines have a compression ratio in the range 8 to 11 and the engine geometry is dictated by the choice of the bore/stroke (B/Ls) ratio in addition to various other design considerations such as the location and size of valves and location of spark plugs. Small engines generally have a B/Ls ratio ranging from 0.7 to 1.3 while large stationary engines have a ratio of less than 0.7. For a given displacement volume, a longer stroke allows for smaller bore which results in less surface area in the combustion chamber with a correspondingly smaller heat loss, which increases thermal efficiency within the combustion chamber. However the longer stroke results in higher piston speed and higher friction losses which reduces the brake power output of the engine. If the stroke is shortened, the bore must be increased which reduces the friction losses but increases the heat transfer losses. This paper presented a simple thermodynamics approach based on one dimensional thermodynamic model of the combustion chamber to establish the appropriate B/Ls ratio depending on the operating conditions of the engine such as its compression ratio, speed, and fuel equivalence ratios, in conjunction with a nearly full fledged simulation program for optimum combustion in spark ignition engines. The paper described the engine test rig as well as the experimental procedure. The development of the mathematical model was also explained. It was concluded that there is a significant relationship between the compression ratio of the engine and the B/Ls ratio. These valves must match for optimum combustion and optimum specific power output. 10 refs., 1 tab., 5 figs.

  16. Mini-projects in Chemical Engineering Laboratory

    Directory of Open Access Journals (Sweden)

    Angeles Cancela

    2013-03-01

    Full Text Available Chemical engineering laboratory practices based in mini-projects were design and applied the students of forestry engineering in chemical subject. This way of practice reveals a more cooperative learning and a different style of experimentation. The stated goal was to design practices that motivate students and to enable them to develop different skills, including cross teamwork and communication. This paper describes how these practices were developed and the advantages and disadvantages of using this methodology of teaching.

  17. Mathematical modeling a chemical engineer's perspective

    CERN Document Server

    Rutherford, Aris

    1999-01-01

    Mathematical modeling is the art and craft of building a system of equations that is both sufficiently complex to do justice to physical reality and sufficiently simple to give real insight into the situation. Mathematical Modeling: A Chemical Engineer's Perspective provides an elementary introduction to the craft by one of the century's most distinguished practitioners.Though the book is written from a chemical engineering viewpoint, the principles and pitfalls are common to all mathematical modeling of physical systems. Seventeen of the author's frequently cited papers are reprinted to illus

  18. Milestones of Chemical Engineering Development in Croatia

    Directory of Open Access Journals (Sweden)

    Hraste, M.

    2007-10-01

    Full Text Available Solving important problems of chemical and process industries stimulated the creation of a new scientific discipline, chemical engineering, which apart from other disciplines includes firm theoretical foundations, core subjects taught to entering students, widely adopted textbooks and journals. The new discipline, at the beginning of the 20th century, provided a way of analyzing the wide variety of processes in terms of small "unit operations". Later, the largely empirical approach of the unit operations was broadened by molecular explanations of macroscopic phenomena. It was not long before chemical engineering extended the operation approach to chemical reaction engineering. At the same time, process optimization prompted the system approach. Instead of looking for details, higher levels of organization were recognized by synthesis. The use of computers has become the key element in process modeling and control. The methods of chemical engineering have extended to other fields, while the discipline keeps the same basis and characteristics.The changes on the global market stimulate new trends in research and education. Product development has become an important segment of the discipline, which presumes an integrated approach to the phenomena and processes at different time and length levels following the possible transfer from molecule to product at process level.This paper mainly deals with the development of this discipline in Croatia, with a preview of the persons that contributed to the acceptance and propagation of the new concepts.

  19. Thermal Loss Determination for a Small Internal Combustion Engine

    Science.gov (United States)

    2014-03-27

    HCCI ) engine . An HCCI engine uses compression ignition on a premixed charge. The difficulty of HCCI operation is in timing control... HCCI engine [10]. This type of engine uses a premixed charge like in gasoline engines but uses compression ignition as in diesel engines . The result is...Smith, and Robert Dibble. “ HCCI Engine Control by Thermal Management”. SAE Transactions, 109(4):2646– 2655, 2000. [11] Mueller, Torsten, Helmut

  20. Cycle-to-cycle fluctuation of combustion in a spark-ignition engine; Hibana tenka engine no nensho hendo

    Energy Technology Data Exchange (ETDEWEB)

    Hamamoto, Y.; Yoshiyama, S.; Tomita, E.; Hamagami, T. [Okayama University, Okayama (Japan); Otsubo, H. [Yammer Diesel Engine Co. Ltd. Tokyo (Japan)

    1997-10-01

    In a homogeneous charge spark-ignition engine, the duration of early stage of combustion is a dominant factor for determining the fluctuation of mean effective pressure. And the early stage of combustion varies with the equivalence ratio and turbulence characteristics of the mixture. In this study, the fluctuations of 1% combustion duration and indicated mean effective pressure Pmi were computed as the function of fluctuations both in the equivalence ratio {phi} of the mixture and in the turbulence characteristics of the cylinder charge. And effects of the spark timing {theta}ig and {phi} on the cycle-to-cycle fluctuation in Pmi were investigated. 16 refs., 6 figs.

  1. Investigation of a Spark Ignition Internal Combustion Engine via IR Spectroscopy

    Science.gov (United States)

    Sakai, Stephen; White, Allen R.; Gross, Kevin; Devasher, Rebecca B.

    2010-06-01

    Previous work has shown that the automotive fuel components of isopropanoland ethanol can be excited by a 10.2 um and 9.3 um CO2 lasers, respectively. Through the use of a monochromator and an indium antimonide detector, the decay time of the excited molecules was measured and found to be significantly long enough to allow for the possibility of experimentation in an internal combustion (IC) engine. In order to pursue In Situ measurements in an internal combustion engine, a MegaTech Mark III transparent engine was modified with a sapphire combustion chamber. This modification will allow the transmission of infrared radiation for time-resolved spectroscopic measurements by an infrared spectrometer. By using a Telops FIRST-MWE imaging Fourier transform spectrometer, temporally and spatially resolved infrared spectral data can be acquired and compared for combustion in the engine both with and without laser excitation. Measurements performed with system provide insight into the energy transfer vectors that precede combustion as well as provide an in situ measurement of the progress of combustion.

  2. Three-dimensional modeling of diesel engine intake flow, combustion and emissions

    Science.gov (United States)

    Reitz, R. D.; Rutland, C. J.

    1992-01-01

    A three-dimensional computer code (KIVA) is being modified to include state-of-the-art submodels for diesel engine flow and combustion: spray atomization, drop breakup/coalescence, multi-component fuel vaporization, spray/wall interaction, ignition and combustion, wall heat transfer, unburned HC and NOx formation, soot and radiation, and the intake flow process. Improved and/or new submodels which were completed are: wall heat transfer with unsteadiness and compressibility, laminar-turbulent characteristic time combustion with unburned HC and Zeldo'vich NOx, and spray/wall impingement with rebounding and sliding drops. Results to date show that adding the effects of unsteadiness and compressibility improves the accuracy of heat transfer predictions; spray drop rebound can occur from walls at low impingement velocities (e.g., in cold-starting); larger spray drops are formed at the nozzle due to the influence of vaporization on the atomization process; a laminar-and-turbulent characteristic time combustion model has the flexibility to match measured engine combustion data over a wide range of operating conditions; and finally, the characteristic time combustion model can also be extended to allow predictions of ignition. The accuracy of the predictions is being assessed by comparisons with available measurements. Additional supporting experiments are also described briefly. To date, comparisons with measured engine cylinder pressure and heat flux data were made for homogeneous charge, spark-ignited and compression-ignited engines. The model results are in good agreement with the experiments.

  3. Internal combustion engines: Computer applications. (Latest citations from the EI Compendex plus database). Published Search

    Energy Technology Data Exchange (ETDEWEB)

    1993-10-01

    The bibliography contains citations concerning the application of computers and computerized simulations in the design, analysis, operation, and evaluation of various types of internal combustion engines and associated components and apparatus. Special attention is given to engine control and performance. (Contains a minimum of 67 citations and includes a subject term index and title list.)

  4. 40 CFR Appendix A to Subpart A of... - State Regulation of Nonroad Internal Combustion Engines

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false State Regulation of Nonroad Internal Combustion Engines A Appendix A to Subpart A of Part 89 Protection of Environment ENVIRONMENTAL PROTECTION...-IGNITION ENGINES General Pt. 89, Subpt. A, App. A Appendix A to Subpart A of Part 89—State Regulation...

  5. Comparisons between measurement and analysis of fluid motion in internal combustion engines

    Energy Technology Data Exchange (ETDEWEB)

    Witze, P.O. (ed.)

    1981-10-01

    The Engine Combustion Technology Project was created for the purpose of promoting the development of advanced piston engine concepts by the development of techniques to measure, analyze, and understand the combustion process. The technologies emphasized in the project include laser-based measurement techniques and large-scale computer simulations. Considerable progress has already been achieved by project participants in modeling engine air motion, fuel sprays, and engine combustion phenomena. This milestone report covers one part of that progress, summarizing the current capabilities of multi-dimensional computer codes being developed by the project to predict the behavior of turbulent air motion in an engine environment. Computed results are compared directly with experimental data in six different areas of importance to internal combustion engines: (1) Induction-generated ring-vortex structures; (2) Piston-induced vortex roll-up; (3) Behavior of turbulence during compression; (4) Decay of swirling flow during compression; (5) Decay of swirling flow in a constant volume engine simulator; (6) Exhaust-pipe flow. The computational procedures used include vortex dynamics, rapid distortion theory, and finite difference models employing two-equation and subgrid-scale turbulence models. Although the capability does not yet exist to predict the air motion in an engine from its geometric configuration alone, the results presented show that many flowfield sub-processes can be predicted given well-specified initial and boundary conditions.

  6. Side branch absorber for exhaust manifold of two-stroke internal combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Harris, Ralph E. (San Antonio, TX); Broerman, III, Eugene L. (San Antonio, TX); Bourn, Gary D. (Laramie, WY)

    2011-01-11

    A method of improving scavenging operation of a two-stroke internal combustion engine. The exhaust pressure of the engine is analyzed to determine if there is a pulsation frequency. Acoustic modeling is used to design an absorber. An appropriately designed side branch absorber may be attached to the exhaust manifold.

  7. Gasdynamic modeling and parametric study of mesoscale internal combustion swing engine/generator systems

    Science.gov (United States)

    Gu, Yongxian

    The demand of portable power generation systems for both domestic and military applications has driven the advances of mesoscale internal combustion engine systems. This dissertation was devoted to the gasdynamic modeling and parametric study of the mesoscale internal combustion swing engine/generator systems. First, the system-level thermodynamic modeling for the swing engine/generator systems has been developed. The system performance as well as the potentials of both two- and four-stroke swing engine systems has been investigated based on this model. Then through parameterc studies, the parameters that have significant impacts on the system performance have been identified, among which, the burn time and spark advance time are the critical factors related to combustion process. It is found that the shorter burn time leads to higher system efficiency and power output and the optimal spark advance time is about half of the burn time. Secondly, the turbulent combustion modeling based on levelset method (G-equation) has been implemented into the commercial software FLUENT. Thereafter, the turbulent flame propagation in a generic mesoscale combustion chamber and realistic swing engine chambers has been studied. It is found that, in mesoscale combustion engines, the burn time is dominated by the mean turbulent kinetic energy in the chamber. It is also shown that in a generic mesoscale combustion chamber, the burn time depends on the longest distance between the initial ignition kernel to its walls and by changing the ignition and injection locations, the burn time can be reduced by a factor of two. Furthermore, the studies of turbulent flame propagation in real swing engine chambers show that the combustion can be enhanced through in-chamber turbulence augmentation and with higher engine frequency, the burn time is shorter, which indicates that the in-chamber turbulence can be induced by the motion of moving components as well as the intake gas jet flow. The burn time

  8. CFD Studies of Split Injection on the Combustion and Emission Characteristics in DI Diesel Engine

    Directory of Open Access Journals (Sweden)

    S Gavudhama karunanidhi

    2014-07-01

    Full Text Available In this study, the effect of split injection on the combustion and emissions in DI diesel engine is investigated using CFD tool .One of the important problems in reducing pollutant emission from diesel engines is trade-off between soot and NOx. Split injection is one of the most powerful tools that decrease soot and NOx emissions simultaneously. Split injection is defined as splitting the main single injection profile in two or more injection pulses with definite delay dwell between the injections. A four-stroke, single cylinder, diesel engine was taken into consideration at constant speed conditions . A model was developed for comprehensive predictions and assessments for variations in combustion phenomenon for DI diesel engines . By using the finite volume method the design and analysis of combustion chamber,emission characteristics were studied. The results of the split injection were compared with single injection and the optimum case of split injection was observed.

  9. Application of micro-genetic algorithm for calibration of kinetic parameters in HCCI engine combustion model

    Institute of Scientific and Technical Information of China (English)

    Haozhong HUANG; Wanhua SU

    2008-01-01

    The micro-genetic algorithm (μGA) as a highly effective optimization method, is applied to calibrate to a newly developed reduced chemical kinetic model (40 species and 62 reactions) for the homogeneous charge compression ignition (HCCI) combustion of n-heptane to improve its autoignition predictions for different engine operating conditions. The seven kinetic parameters of the calibrated model are determined using a combination of the Micro-Genetic Algorithm and the SENKIN program of CHEMKIN chemical kinetics software package. Simulation results show that the autoignition predictions of the calibrated model agree better with those of the detailed chemical kinetic model (544 species and 2 446 reactions) than the original model over the range of equivalence ratios from 0.1-1.3 and temperature from 300-3 000 K. The results of this study have demonstrated that the μGA is an effective tool to facilitate the calibration of a large number of kinetic parameters in a reduced kinetic model.

  10. Fuel/oxidizer-rich high-pressure preburners. [staged-combustion rocket engine

    Science.gov (United States)

    Schoenman, L.

    1981-01-01

    The analyses, designs, fabrication, and cold-flow acceptance testing of LOX/RP-1 preburner components required for a high-pressure staged-combustion rocket engine are discussed. Separate designs of injectors, combustion chambers, turbine simulators, and hot-gas mixing devices are provided for fuel-rich and oxidizer-rich operation. The fuel-rich design addresses the problem of non-equilibrium LOX/RP-1 combustion. The development and use of a pseudo-kinetic combustion model for predicting operating efficiency, physical properties of the combustion products, and the potential for generating solid carbon is presented. The oxygen-rich design addresses the design criteria for the prevention of metal ignition. This is accomplished by the selection of materials and the generation of well-mixed gases. The combining of unique propellant injector element designs with secondary mixing devices is predicted to be the best approach.

  11. Diesel-Minimal Combustion Control of a Natural Gas-Diesel Engine

    Directory of Open Access Journals (Sweden)

    Florian Zurbriggen

    2016-01-01

    Full Text Available This paper investigates the combustion phasing control of natural gas-diesel engines. In this study, the combustion phasing is influenced by manipulating the start and the duration of the diesel injection. Instead of using both degrees of freedom to control the center of combustion only, we propose a method that simultaneously controls the combustion phasing and minimizes the amount of diesel used. Minimizing the amount of diesel while keeping the center of combustion at a constant value is formulated as an optimization problem with an equality constraint. A combination of feedback control and extremum seeking is used to solve this optimization problem online. The necessity to separate the different time scales is discussed and a structure is proposed that facilitates this separation for this specific example. The proposed method is validated by experiments on a test bench.

  12. Drug Transport and Pharmacokinetics for Chemical Engineers

    Science.gov (United States)

    Simon, Laurent; Kanneganti, Kumud; Kim, Kwang Seok

    2010-01-01

    Experiments in continuous-stirred vessels were proposed to introduce methods in pharmacokinetics and drug transport to chemical engineering students. The activities can be incorporated into the curriculum to illustrate fundamentals learned in the classroom. An appreciation for the role of pharmacokinetics in drug discovery will also be gained…

  13. Centrifugal Pump Experiment for Chemical Engineering Undergraduates

    Science.gov (United States)

    Vanderslice, Nicholas; Oberto, Richard; Marrero, Thomas R.

    2012-01-01

    The purpose of this paper is to describe a Centrifugal Pump Experiment that provided an experiential learning experience to chemical engineering undergraduates at the University of Missouri in the spring of 2010 in the Unit Operations Laboratory course. Lab equipment was used by senior students with computer-based data and control technology. In…

  14. Chemical engineering education: a gallimaufry of thoughts.

    Science.gov (United States)

    Bird, R Byron

    2010-01-01

    To discuss various facets of chemical engineering education, I proceed step by step through my own education and career. In this way, I touch on various points concerning the operation of the educational system that may be of interest to others.

  15. Interactive Mathematica Simulations in Chemical Engineering Courses

    Science.gov (United States)

    Falconer, John L.; Nicodemus, Garret D.

    2014-01-01

    Interactive Mathematica simulations with graphical displays of system behavior are an excellent addition to chemical engineering courses. The Manipulate command in Mathematica creates on-screen controls that allow users to change system variables and see the graphical output almost instantaneously. They can be used both in and outside class. More…

  16. Conceptests for a Chemical Engineering Thermodynamics Course

    Science.gov (United States)

    Falconer, John L.

    2007-01-01

    Examples of conceptests and suggestions for preparing them for use in an undergraduate, chemical engineering thermodynamics course are presented. Conceptests, combined with hand-held transmitters (clickers), is an effective method to engage students in class. This method motivates students, improves their functional understanding of…

  17. Chemical engineering of Mycobacterium tuberculosis dodecin hybrids.

    Science.gov (United States)

    Vinzenz, Xenia; Grosse, Wolfgang; Linne, Uwe; Meissner, Britta; Essen, Lars-Oliver

    2011-10-21

    The suitability for chemical engineering of the highly symmetrical Mycobacterium tuberculosis dodecin was investigated, its inner cavity providing a large compartment shields introduced compounds from bulk solvent. Hybrids were obtained by S-alkylation of cysteine mutants and characterized by spectroscopic methods, including the crystal structures of wild type and biohybrid dodecins.

  18. Chemical reduction of complex kinetic models of combustion; Reduction chimique des modeles cinetiques complexes de combustion

    Energy Technology Data Exchange (ETDEWEB)

    Fournet, R.; Glaude, P.A.; Warth, V.; Battin-Leclerc, F.; Scacchi, G.; Come, G.M. [Institut National Polytechnique de Lorraine, Ecole Nationale Superieure des Industries Chimiques, CNRS UMR 7630, INPL ENSIC, Dept. de Chimie Physique des Reacteurs, 54 - Nancy (France)

    2001-07-01

    This paper presents an automatized method allowing to notably reduce the size of the primary mechanism of alkane combustion. The free radicals having the same raw formulation and the same functional groups are presented in a global way as a unique species. In this way, the number of radicals can be divided by a factor of 16 in the case of n-heptane combustion. The kinetic parameters linked with the global mechanism are obtained from a weighted average of the kinetic constants of the detailed mechanism, and this without any adjustment.The simulations performed for the combustion mechanisms of the n-heptane and of a mixture of n-heptane and 2,2,3 trimethyl butane are presented in order to show the validity of the proposed method. (J.S.)

  19. Ceramic-coated components for the combustion zone of natural gas engines

    Science.gov (United States)

    Holloman, L.; Levy, A. V.

    1992-03-01

    The use of ceramic coatings on the combustion zone surfaces of large,natural gas-fueled,internal com-bustion engines is discussed. Unique handling and quality control systems are required for plasma spray-ing thin (0.25 mm,0.0010) in.coatings on up to 48.25(cm19)-in.diameter piston crowns and cylinder heads weighing up to(1200 lb).The in-service performance characteristics of two types of natural gas-fu-eled combustion engines powering natural gas compressors that had thin zirconia ceramic coatings ap-plied to their combustion zone surfaces are presented. Their performance was measured in the field be-fore and after coating. It was determined that the durability,power output,fuel consumption,exhaust emissions,and other operating characteristics all improved due to ceramic coating of the flame side sur-faces of cylinder heads,power pistons,and valves.

  20. Co-combustion of coal and sewage sludge: chemical and ecotoxicological properties of ashes.

    Science.gov (United States)

    Barbosa, Rui; Lapa, Nuno; Boavida, Dulce; Lopes, Helena; Gulyurtlu, Ibrahim; Mendes, Benilde

    2009-10-30

    The co-combustion of sewage sludge (SS) and coal is widely used for the treatment and thermal valorization of SS produced in wastewater treatment plants. The chemical and ecotoxicological properties of the ashes produced in this thermal treatment have not been fully studied. Two combustion tests were performed in a fluidized bed combustor. Colombian coal was used as fuel in test A. A blend (1+1) of this coal and a stabilized SS (Biogran) was used in a second test B. Samples of the bottom and fly ashes trapped in two sequential cyclones were collected. The characterization of the ashes was focused on two main aspects: (1) the bulk content of a set of metals and (2) the characterization of eluates produced according to the European Standard leaching test EN 12457-2. The eluates were submitted to an ecotoxicological characterization for two bio-indicators. In what concerns the bulk content of ashes, both combustion tests have produced ashes with different compositions. The ashes formed during the co-combustion test have shown higher concentrations of metals, namely Cr, Cu, Ni, Pb, Zn and Fe for all ashes. The leaching test has shown low mobility of these elements from the by-products produced during the combustion and co-combustion tests. Cr and Cr(VI) were mainly detected in the eluates of the 1st cyclone ashes produced in both combustion tests and in the 2nd cyclone ashes produced in the co-combustion test. Considering the ecotoxicity assays, the eluates of bottom and fly ashes for both combustion and co-combustion tests have shown low ecotoxic levels. The micro-crustacean Daphnia magna was generally more sensitive than the bacterium Vibrio fischeri. CEMWE criterion has allowed to classify the bottom ashes for both combustion and co-combustion tests as non-toxic residues and the fly ashes collected in both cyclones as toxic.

  1. Numerical study of premixed HCCI engine combustion and its sensitivity to computational mesh and model uncertainties

    Science.gov (United States)

    Kong, Song-Charng; Reitz, Rolf D.

    2003-06-01

    This study used a numerical model to investigate the combustion process in a premixed iso-octane homogeneous charge compression ignition (HCCI) engine. The engine was a supercharged Cummins C engine operated under HCCI conditions. The CHEMKIN code was implemented into an updated KIVA-3V code so that the combustion could be modelled using detailed chemistry in the context of engine CFD simulations. The model was able to accurately simulate the ignition timing and combustion phasing for various engine conditions. The unburned hydrocarbon emissions were also well predicted while the carbon monoxide emissions were under predicted. Model results showed that the majority of unburned hydrocarbon is located in the piston-ring crevice region and the carbon monoxide resides in the vicinity of the cylinder walls. A sensitivity study of the computational grid resolution indicated that the combustion predictions were relatively insensitive to the grid density. However, the piston-ring crevice region needed to be simulated with high resolution to obtain accurate emissions predictions. The model results also indicated that HCCI combustion and emissions are very sensitive to the initial mixture temperature. The computations also show that the carbon monoxide emissions prediction can be significantly improved by modifying a key oxidation reaction rate constant.

  2. Cyclic Combustion Variations in Dual Fuel Partially Premixed Pilot-Ignited Natural Gas Engines

    Energy Technology Data Exchange (ETDEWEB)

    Srinivasan, K. K. [Mississippi State Univ., MS (United States). Dept. of Mechanical Engineering; Krishnan, S. R. [Mississippi State Univ., MS (United States). Dept. of Mechanical Engineering; Qi, Y. [Caterpillar, Inc., Peoria, IL (United States)

    2012-05-09

    Dual fuel pilot ignited natural gas engines are identified as an efficient and viable alternative to conventional diesel engines. This paper examines cyclic combustion fluctuations in conventional dual fuel and in dual fuel partially premixed low temperature combustion (LTC). Conventional dual fueling with 95% (energy basis) natural gas (NG) substitution reduces NOx emissions by almost 90%t relative to straight diesel operation; however, this is accompanied by 98% increase in HC emissions, 10 percentage points reduction in fuel conversion efficiency (FCE) and 12 percentage points increase in COVimep. Dual fuel LTC is achieved by injection of a small amount of diesel fuel (2-3 percent on an energy basis) to ignite a premixed natural gas₋air mixture to attain very low NOx emissions (less than 0.2 g/kWh). Cyclic variations in both combustion modes were analyzed by observing the cyclic fluctuations in start of combustion (SOC), peak cylinder pressures (Pmax), combustion phasing (Ca50), and the separation between the diesel injection event and Ca50 (termed "relative combustion phasing" ). For conventional dual fueling, as % NG increases, Pmax decreases, SOC and Ca50 are delayed, and cyclic variations increase. For dual fuel LTC, as diesel injection timing is advanced from 20° to 60° BTDC, the relative combustion phasing is identified as an important combustion parameter along with SoC, Pmax, and CaPmax. For both combustion modes, cyclic variations were characterized by alternating slow and fast burn cycles, especially at high %NG and advanced injection timings. Finally, heat release return maps were analyzed to demonstrate thermal management strategies as an effective tool to mitigate cyclic combustion variations, especially in dual fuel LTC.

  3. Chemical-text hybrid search engines.

    Science.gov (United States)

    Zhou, Yingyao; Zhou, Bin; Jiang, Shumei; King, Frederick J

    2010-01-01

    As the amount of chemical literature increases, it is critical that researchers be enabled to accurately locate documents related to a particular aspect of a given compound. Existing solutions, based on text and chemical search engines alone, suffer from the inclusion of "false negative" and "false positive" results, and cannot accommodate diverse repertoire of formats currently available for chemical documents. To address these concerns, we developed an approach called Entity-Canonical Keyword Indexing (ECKI), which converts a chemical entity embedded in a data source into its canonical keyword representation prior to being indexed by text search engines. We implemented ECKI using Microsoft Office SharePoint Server Search, and the resultant hybrid search engine not only supported complex mixed chemical and keyword queries but also was applied to both intranet and Internet environments. We envision that the adoption of ECKI will empower researchers to pose more complex search questions that were not readily attainable previously and to obtain answers at much improved speed and accuracy.

  4. Estimation of the combustion-related noise transfer matrix of a multi-cylinder diesel engine

    Science.gov (United States)

    Lee, Moohyung; Bolton, J. Stuart; Suh, Sanghoon

    2009-01-01

    In the present paper, a procedure for estimating an engine-platform-dependent transfer matrix that relates in-cylinder pressures to radiated noise resulting from processes associated with the combustion process is described. A knowledge of that transfer matrix allows the combustion-related component of the noise radiated by a diesel engine to be estimated from a knowledge of cylinder pressure signals. The procedure makes use of multi-input/multi-output (MIMO) system modeling concepts in conjunction with cross-spectral measurements. To date, the empirical prediction of diesel engine combustion noise has usually been achieved by combining a cylinder pressure with a single, smooth structural attenuation function (e.g., the Lucas combustion noise meter) regardless of the specifications of the engine. In comparison, the procedure described in the present work provides the structural attenuation characteristics of a particular engine in the form of a transfer matrix, thus allowing accurate prediction by accounting fully for inter-cylinder correlation, cylinder-to-cylinder variation and the detailed characteristics of an engine structure. The procedure was applied to a six-cylinder diesel engine, and the various aspects of the new procedure are described.

  5. Analysis of an Internal Combustion Engine Using Porous Foams for Thermal Energy Recovery

    Directory of Open Access Journals (Sweden)

    Mehdi Ali Ehyaei

    2016-03-01

    Full Text Available Homogeneous and complete combustion in internal combustion engines is advantageous. The use of a porous foam in the exhaust gas in an engine cylinder for heat recovery is examined here with the aim of reducing engine emissions. The internal combustion engine with a porous core regenerator is modeled using SOPHT software, which solved the differential equations for the thermal circuit in the engine. The engine thermal efficiency is observed to increase from 43% to 53% when the porous core regenerator is applied. Further, raising the compression ratio causes the peak pressure and thermal efficiency to increase, e.g., increasing the compression ratio from 13 to 15 causes the thermal efficiency and output work to increase from 53% to 55% and from 4.86 to 4.93 kJ, respectively. The regenerator can also be used as a catalytic converter for fine particles and some other emissions. The regenerator oxidizes unburned hydrocarbons. Meanwhile, heat recovered from the exhaust gases can reduce fuel consumption, further reducing pollutant emissions from the internal combustion engine.

  6. Emission and Combustion Characteristics of Si Engine Working Under Gasoline Blended with Ethanol Oxygenated Organic Compounds

    Directory of Open Access Journals (Sweden)

    Dhanapal Balaji

    2010-01-01

    Full Text Available Problem statement: The objective of this study is to investigate the effect of using unleaded gasoline and additives blends on Spark Ignition engine (SI engine combustion and exhaust emission. Approach: A four stroke, single cylinder SI engine was used for conducting this study. Exhaust emissions were analysed for Carbon Monoxide (CO, Hydrocarbon (HC and Oxides of Nitrogen (NOx and carbon dioxide (CO2 using unleaded gasoline and additives blends with different percentages of fuel at varying engine torque condition and constant engine speed. Results: The result showed that the blending of unleaded gasoline increases the octane number and power output this may leads to increase the brake thermal efficiency. The CO, HC and NOx emissions concentrations in the engine exhaust decreases while the CO2 concentration increases. Conclusion: Using ethanol as a fuel additive to unleaded gasoline causes an improvement in combustion characteristics and significant reduction in exhaust emissions.

  7. Combustion Property Analysis and Control System for the Dynamics of a Single Cylinder Diesel Engine

    Directory of Open Access Journals (Sweden)

    Bambang Wahono

    2013-12-01

    Full Text Available Corresponding to global environment problems in recent year, the technology for reducing fuel consumption and exhaust gas emission of engine was needed. Simulation of transient engine response is needed to predict engine performance that frequently experience rapid changes of speed. The aim of this research is to develop a non-linear dynamic control model for direct injection single cylinder diesel engine which can simulate engine performance under transient conditions. In this paper, the combustion model with multistage injection and conducted experiments in the transient conditions to clarify the combustion characteristics was proposed. In order to perform the analysis of acceleration operation characteristics, it was built a Model Predictive Control (MPC to reproduce the characteristic values of the exhaust gas and fuel consumption from the control parameters in particular. Finally, MPC is an effective method to perform the analysis of characteristic in diesel engine under transient conditions.

  8. Fuel injection for internal combustion engines. (Latest citations from the NTIS bibliographic database). Published Search

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-08-01

    The bibliography contains citations concerning research and development of fuel injection systems applied to internal combustion engines and turbines. Gasoline, diesel, synthetic fuels, and liquid gas systems are discussed relative to systems` variations and performances. Fuel injection atomization and combustion are considered in theory, and fuel injection relative to emission control is included.(Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  9. Fuel injection for internal combustion engines. (Latest citations from the NTIS Bibliographic database). Published Search

    Energy Technology Data Exchange (ETDEWEB)

    1993-09-01

    The bibliography contains citations concerning research and development of fuel injection systems applied to internal combustion engines and turbines. Gasoline, diesel, synthetic fuels, and liquid gas systems are discussed relative to systems' variations and performances. Fuel injection atomization and combustion are considered in theory, and fuel injection relative to emission control is included. (Contains a minimum of 223 citations and includes a subject term index and title list.)

  10. Multidimensional Modeling of Fuel Composition Effects on Combustion and Cold-starting in Diesel Engines

    Science.gov (United States)

    1995-01-01

    equally important for both the gas and liquid phase. For the gas phase, a modified Redlich - Kwong equation of state is used (Prausnitz, [lo]). In the...residual fuel mass (case 9). Ignition started early but the combustion developed at a slower rate. Another application of an altered engine geometry...Power, Vol. 115, pp. 781-789,1993. 17. Kong, S.C., Han, Z., and Reitz, R.D., “The Development and Application of a Diesel Ignition and Combustion

  11. Big Data Analytics in Chemical Engineering.

    Science.gov (United States)

    Chiang, Leo; Lu, Bo; Castillo, Ivan

    2017-02-27

    Big data analytics is the journey to turn data into insights for more informed business and operational decisions. As the chemical engineering community is collecting more data (volume) from different sources (variety), this journey becomes more challenging in terms of using the right data and the right tools (analytics) to make the right decisions in real time (velocity). This article highlights recent big data advancements in five industries, including chemicals, energy, semiconductors, pharmaceuticals, and food, and then discusses technical, platform, and culture challenges. To reach the next milestone in multiplying successes to the enterprise level, government, academia, and industry need to collaboratively focus on workforce development and innovation. Expected final online publication date for the Annual Review of Chemical and Biomolecular Engineering Volume 8 is June 7, 2017. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

  12. The combustion system of the MAN 20V35/44G gas engine

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, Markus; Auer, Matthias; Stiesch, Gunnnar [MAN Diesel and Turbo SE, Augsburg (Germany)

    2013-05-15

    The new gas engine 20V35/44G by MAN Diesel and Turbo SE has a power output of 10.6 MW. The high effective efficiency level of 48.4 % as well as numerous technical innovations allow an environmentally-friendly, economical and reliable engine operation. Key to achieve this is the combustion system, which has been optimised during advanced engineering by means of modern simulation tools and extensive single-cylinder tests. (orig.)

  13. Method and systems for power control of internal combustion engines using individual cycle cut-off

    Energy Technology Data Exchange (ETDEWEB)

    Fedorenko, Y.; Korzhov, M.; Filippov, A.; Atamanenko, N.

    1996-09-01

    A new method of controlling power has been developed for improving efficiency and emissions performance of internal combustion engines at partial load. The method involves cutting-off some of the work cycles, as the load decreases, to obtain required power. Theoretical and experimental material is presented to illustrate the underlying principle, the implementation means and the results for the 4- and 8-cylinder piston engine and a twin rotor Wankel engine applications.

  14. Miniature Internal Combustion Engine-Generator for High Energy Density Portable Power

    Science.gov (United States)

    2008-12-01

    very effective at maintaining a constant voltage and stroke as the HCCI combustion pressure varies during engine warmup. The current is modulated by the...Comparison of Measured and Predicted Two- Stroke Engine Power Output for Jet-A and Propane 5 The exhaust emissions of the 300 W MICE generator with HCCI ...1 Two-Stroke Engine Double- Helix Spring Linear Alternator Magnet Pole Permanent Magnet Alternator Coil Spring Casing Coil Standoff Double-Helix

  15. Liquid propellant rocket engine combustion simulation with a time-accurate CFD method

    Science.gov (United States)

    Chen, Y. S.; Shang, H. M.; Liaw, Paul; Hutt, J.

    1993-01-01

    Time-accurate computational fluid dynamics (CFD) algorithms are among the basic requirements as an engineering or research tool for realistic simulations of transient combustion phenomena, such as combustion instability, transient start-up, etc., inside the rocket engine combustion chamber. A time-accurate pressure based method is employed in the FDNS code for combustion model development. This is in connection with other program development activities such as spray combustion model development and efficient finite-rate chemistry solution method implementation. In the present study, a second-order time-accurate time-marching scheme is employed. For better spatial resolutions near discontinuities (e.g., shocks, contact discontinuities), a 3rd-order accurate TVD scheme for modeling the convection terms is implemented in the FDNS code. Necessary modification to the predictor/multi-corrector solution algorithm in order to maintain time-accurate wave propagation is also investigated. Benchmark 1-D and multidimensional test cases, which include the classical shock tube wave propagation problems, resonant pipe test case, unsteady flow development of a blast tube test case, and H2/O2 rocket engine chamber combustion start-up transient simulation, etc., are investigated to validate and demonstrate the accuracy and robustness of the present numerical scheme and solution algorithm.

  16. FUEL EFFECTS ON COMBUSTION WITH EGR DILUTION IN SPARK IGNITED ENGINES

    Energy Technology Data Exchange (ETDEWEB)

    Szybist, James P [ORNL

    2016-01-01

    The use of EGR as a diluent allows operation with an overall stoichiometric charge composition, and the addition of cooled EGR results in well-understood thermodynamic benefits for improved fuel consumption. This study investigates the effect of fuel on the combustion and emission response of EGR dilution in spark ignited engines. A 2.0 L GM Ecotec LNF engine equipped with the production side-mounted direct injection (DI) fueling system is used in this study. Ethanol, isooctane and certified gasoline are investigated with EGR from 0% to the EGR dilution tolerance. Constant BMEP at 2000 rpm was operated with varying CA50 from 8 CAD to 16 CAD aTDCf. The results show that ethanol gives the largest EGR tolerance at a given combustion phasing, engine load and speed. The improved EGR dilution tolerance with ethanol is attributed to a faster flame speed, which manifests itself as shorter combustion duration. Data shows that the combustion stability limit occurs at a critical combustion duration that is fuel independent. Due to different flame speeds, this critical combustion duration occurs at different EGR levels for the different fuels.

  17. A New Strategy to Achieve Radical Combustion Through Exhaust Port Throttling for Two Stroke Engine

    Directory of Open Access Journals (Sweden)

    Saqaff Ahmed Alkaff, Mohamed A. Khan

    2010-06-01

    Full Text Available Radical combustion is a critical condition behind control. In two stroke engine, acondition of radical combustion could be achieved through control of the trappedexhaust gases at a certain condition, might include, the engine load, speed,concentration of the unburned hydrocarbons, their temperature and otheroperational parameters.An earlier work was conducted towards the achievement of the radicalcombustion. The mechanism was made to throttle the opening of the exhaustport at a range of 1% to 8 % [1]. However, several difficulties were faced, mainlywith the control mechanism of throttling. In addition there is a complexity inidentifying the critical conditions at which the radical combustion could beachieved.In this paper, a new strategy was used to control the exhaust port throttling in away to manage the amount of exhaust gases trapped and avoiding thedrawbacks of the throttling mechanism in the earlier work. Three trial plateswere used, one-sixth closed, one-third closed and half closed to throttle theexhaust gases leaving the combustion chamber.Results reveal the possibility of achieving radical combustion, when using theone-sixth closed plate under relatively higher load. Therefore, partial trapping ofthe exhaust gases should be carried, through the restriction of the opening of theexhaust port not to exceed 15% of the port exit area. However, it is moreinteresting, that throttling of the exhaust gases of the two stroke engine haveclear influence on the quality and stability of the combustion and hence its directeffect on the fuel consumption and the rate of pollutants expelled to theenvironment.

  18. Combustion and Vibration Analysis of Idi- Diesel Engine Fuelled With Neat Preheated Jatropha Methyl Ester

    Directory of Open Access Journals (Sweden)

    Y.Ashok Kumar Reddy

    2014-03-01

    Full Text Available Experimentation is conducted on an IDI diesel engine and the results of combustion and vibration on IDI -Diesel engine fueled with the preheated Jatropha Methyl Ester (JME are presented. The Present research trend is to replace conventional diesel by renewable alternative fuels in view of fast depletion of petroleum reserves and to reduce the exhaust emissions from the engines without altering the basic design of the engine. Due to moderately higher viscosity effects, the direct use of biodiesel in C.I. engines is limited to 20% and the limitation is based on the NO emission also. In this work, the biodiesel is preheated using on line electronically controlled electrical preheating system before it enters into the injector. Experiments are conducted on a four stroke single cylinder IDI engine to find combustion and vibration characteristics of the engine with the preheated Jatropha Methyl Ester (JME heated to temperatures viz. 60,70,80,90 and 1000C. Normally thin oils due to heating may trigger fast burning leading to either detonation or knocking of the engine. This can be predicted by recording vibration on the cylinder head in different directions. The cylinder vibrations in the form of FFT and time waves have been analyzed to estimate the combustion propensity. Experiments are done using diesel, biodiesel and biodiesel at different preheated temperatures and for different engine loading conditions keeping the speed constant at 1500 rpm. Biodiesel preheated to 600C proved encouraging in all respects.

  19. Combustible radioactive waste treatment by incineration and chemical digestion

    Energy Technology Data Exchange (ETDEWEB)

    Stretz, L.A.; Crippen, M.D.; Allen, C.R.

    1980-05-28

    A review is given of present and planned combustible radioactive waste treatment systems in the US. Advantages and disadvantages of various systems are considered. Design waste streams are discussed in relation to waste composition, radioactive contaminants by amount and type, and special operating problems caused by the waste.

  20. Application of neural network in the study of combustion rate of natural gas/diesel dual fuel engine

    Institute of Scientific and Technical Information of China (English)

    严兆大; 周重光; 苏石川; 刘震涛; 王希珍

    2003-01-01

    In order to predict and improve the performance of natural gas/diesel dual fuel engine (DFE), a combustion rate model based on forward neural network was built to study the combustion process of the DFE. The effect of the operating parameters on combustion rate was also studied by means of this model. The study showed that the predicted results were good agreement with the experimental data. It was proved that the developed combustion rate model could be used to successfully predict and optimize the combustion process of dual fuel engine.

  1. Application of neural network in the study of combustion rate of natural gas/diesel dual fuel engine

    Institute of Scientific and Technical Information of China (English)

    严兆大; 周重光; 苏石川; 刘震涛; 王希珍

    2003-01-01

    In order to predict and improve the performance of matural gas/diesel dual fuel engine(DFE),a combustion rate model based on forward meural network was built to study the combustion process of the DFE.The effect of the operating parameters on combustion rate was also studied by means of this model.The study showed that the predicted results were good agreement with the experimental data.It was proved that the de-veloped combustion rate model could be used to successfully predict and optimize the combustion process of dual fuel engine.

  2. Internal combustion engine system having a power turbine with a broad efficiency range

    Science.gov (United States)

    Whiting, Todd Mathew; Vuk, Carl Thomas

    2010-04-13

    An engine system incorporating an air breathing, reciprocating internal combustion engine having an inlet for air and an exhaust for products of combustion. A centripetal turbine receives products of the combustion and has a housing in which a turbine wheel is rotatable. The housing has first and second passages leading from the inlet to discrete, approximately 180.degree., portions of the circumference of the turbine wheel. The passages have fixed vanes adjacent the periphery of the turbine wheel and the angle of the vanes in one of the passages is different than those in the other so as to accommodate different power levels providing optimum approach angles between the gases passing the vanes and the blades of the turbine wheel. Flow through the passages is controlled by a flapper valve to direct it to one or the other or both passages depending upon the load factor for the engine.

  3. INFLUENCE OF SWIRL ON SPRAY CHARACTERISTICS AND COMBUSTION, A NUMERICAL INVESTIGATION OF A CATERPILLER DIESEL ENGINE

    Directory of Open Access Journals (Sweden)

    M. SREENIVASULU

    2012-10-01

    Full Text Available The purpose of this study is to find the appropriate swirl ratio at which a DI diesel engine should be operated. In the process of identifying an appropriate swirl, the combustion behaviour was analysed by considering Pressure variations and Heat Release Rate variations against crank angle. The spray characteristics were also analysed by considering Penetration lengths, Sauter mean diameters, Spray cone angles against crank angle. Final conclusions were derived by considering NOx emission levels. A turbo charged DI diesel engine geometry was considered for the analysis. Proper care was taken inidentifying the range of Swirl Ratios. A 3-dimensional CFD code (RECARDO VECTIS, which is capable of solving 3-dimensional unsteady, turbulent flows, sprays and combustion of IC engines was used. In the first step CFD code was validated by comparing the obtained results with the experimental results. In the next step an attempt was made to study the influence of swirl on the spray characteristics and combustion.

  4. Combustion characteristics of SI engine fueled with methanol-gasoline blends during cold start

    Institute of Scientific and Technical Information of China (English)

    Ruizhi SONG; Tiegang HU; Shenghua LIU; Xiaoqiang LIANG

    2008-01-01

    A 3-cylinder port fuel injection (PFI) engine fueled with methanol-gasoline blends was used to study combustion and emission characteristics. Cylinder pres-sure analysis indicates that engine combustion is improved when methanol is added to gasoline. With the increase of methanol, the flame developing period and the rapid combustion period are shortened, and the indicated mean effective pressure increases during the first 50 cycles. Meanwhile, a novel quasi-instantaneous sampling system was designed to measure engine emissions during cold start and warm-up. The results at 5℃ show that unburned hydrocarbon (UHC) and carbon monoxide (CO) decrease remarkably. Hydrocarbon (HC) reduces by 40% and CO by 70% when fueled with M30 (30% methanol in volume). The exhaust gas temperature is about 140℃ higher at 200 s after operation compared with that of gasoline.

  5. The Influence of Hydrogen Gas on the Measures of Efficiency of Diesel Internal Combustion Engine

    Directory of Open Access Journals (Sweden)

    Jurgis Latakas

    2014-12-01

    Full Text Available In this research paper energy and ecological parameters of diesel engine which works under addition of hydrogen (10, 20, 30 l/ min are presented. A survey of research literature has shown that addition of hydrogen gases improve diesel combustion; increase indicated pressure; decrease concentration of carbon dioxide (CO2, hydrocarbons (HC, particles; decrease fuel consumptions. Results of the experiment revealed that hydrogen gas additive decreased pressure in cylinder in kinetic combustion phase. Concentration of CO2 and nitrous oxides (NOx decreased not significantly, HC – increased. Concentration of particles in engine exhaust gases significantly decreased. In case when hydrogen gas as additive was supplied, the fuel consumptions decreased a little. Using AVL BOOST software combustion process analysis was made. It was determined that in order to optimize engine work process under hydrogen additive usage, it is necessary to adjust diesel injection angle.

  6. Simulation Analysis of Combustion Parameters and Emission Characteristics of CNG Fueled HCCI Engine

    Directory of Open Access Journals (Sweden)

    P. M. Diaz

    2013-01-01

    Full Text Available The naturally aspirated compressed natural gas (CNG fueled homogeneous charge compression ignition (HCCI engine operation region is narrow between heavy knock at rich air-fuel mixture side and misfire at the lean air-fuel mixture side. However, high activation energy is needed to attain autoignition temperature of CNG fueled HCCI engine. This paper seeks to provide guidance in overcoming challenges of CNG fueled HCCI engine by using CHEMKIN. It is used to investigate the fundamental characteristics of the homogeneous charge compression ignition combustion process for different air-fuel mixture inlet temperature, relative air-fuel ratio of 2.5, and with hemispherical bowl types of combustion chambers. The variation of various properties like the peak cylinder pressure, peak cylinder temperature, CO emission, NO emission, soot emission, and HC emission are studied. It is necessary to develop new combustion models to simulate and predict all parameters with high accuracy.

  7. NUMERICAL STUDIES ON HYDROGEN COMBUSTION IN A FILM COOLED CRYOGENIC ROCKET ENGINE

    Directory of Open Access Journals (Sweden)

    ARSHAD A.

    2012-07-01

    Full Text Available Liquid rocket engines have variety of propellant combinations which produces very high specific impulses. It is due to this fact; very high heat fluxes are incident on the combustion chamber and the nozzle walls. In order to deal with these heat fluxes, a wide range of cooling techniques have been employed, out of which a combination of film cooling and regenerative cooling promises to be the most effective one. The present study involves the numerical analysis of combustion in a typical film cooled cryogenic rocket engine thrust chamber considering the combustion of the fuel, heat transfer through the chamber walls and the fluid flow simultaneously. Analysis was done for a typical rocket engine thrust chamber with a single coaxial injector which uses gaseous hydrogen as the fuel and liquid oxygen as the oxidizer.

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

    Science.gov (United States)

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

    2016-09-01

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

  9. A Mixing Based Model for DME Combustion in Diesel Engines

    DEFF Research Database (Denmark)

    Bek, Bjarne H.; Sorenson, Spencer C.

    1998-01-01

    A series of studies has been conducted investigating the behavior of di-methyl ether (DME) fuel jets injected into quiescent combus-tion chambers. These studies have shown that it is possible to make a good estimate of the penetration of the jet based on existing correlations for diesel fuel...

  10. A mixing based model for DME combustion in diesel engines

    DEFF Research Database (Denmark)

    Bek, Bjarne Hjort; Sorenson, Spencer C

    2001-01-01

    A series of studies has been conducted investigating the behavior of di-methyl ether (DME) fuel jets injected into quiescent combustion chambers. These studies have shown that it is possible to make a good estimate of the penetration of the jet based on existing correlations for diesel fuel...

  11. Engineered Barrier System: Physical and Chemical Environment

    Energy Technology Data Exchange (ETDEWEB)

    P. Dixon

    2004-04-26

    The conceptual and predictive models documented in this Engineered Barrier System: Physical and Chemical Environment Model report describe the evolution of the physical and chemical conditions within the waste emplacement drifts of the repository. The modeling approaches and model output data will be used in the total system performance assessment (TSPA-LA) to assess the performance of the engineered barrier system and the waste form. These models evaluate the range of potential water compositions within the emplacement drifts, resulting from the interaction of introduced materials and minerals in dust with water seeping into the drifts and with aqueous solutions forming by deliquescence of dust (as influenced by atmospheric conditions), and from thermal-hydrological-chemical (THC) processes in the drift. These models also consider the uncertainty and variability in water chemistry inside the drift and the compositions of introduced materials within the drift. This report develops and documents a set of process- and abstraction-level models that constitute the engineered barrier system: physical and chemical environment model. Where possible, these models use information directly from other process model reports as input, which promotes integration among process models used for total system performance assessment. Specific tasks and activities of modeling the physical and chemical environment are included in the technical work plan ''Technical Work Plan for: In-Drift Geochemistry Modeling'' (BSC 2004 [DIRS 166519]). As described in the technical work plan, the development of this report is coordinated with the development of other engineered barrier system analysis model reports.

  12. Genetic Algorithm-Based Design Optimization of Electromagnetic Valve Actuators in Combustion Engines

    Directory of Open Access Journals (Sweden)

    Seung Hwan Lee

    2015-11-01

    Full Text Available In this research, the design of a new electromagnetic engine valve in the limited space of combustion engine is optimized by multidisciplinary simulation using MATLAB and Maxwell. An electromagnetic engine valve actuator using a permanent magnet is a new actuator concept for overcoming the inherent drawbacks of the conventional solenoid-driven electromagnetic engine valve actuator, such as high power consumption and so on. This study aims to maximize the vibration frequency of the armature to reduce the transition time of the engine valve. The higher performance of the new actuator is demonstrated by dynamic finite element analysis.

  13. Fluid motion within the cylinder of internal combustion engines - The 1986 Freeman Scholar Lecture

    Science.gov (United States)

    Heywood, John B.

    1987-03-01

    Aspects of gas motion into, within, and out of the engine cylinder which govern the combustion characteristics and capabilities of spark-ignition engines and compression-ignition or diesel engines are considered. Flow characteristics through inlet and exhaust valves in four-stroke cycle engines, and through ports in the cylinder liner in two-stroke cycle engines, are discussed. Features and turbulence characteristics of common in-cylinder flows including the large scale rotating flows precipitated by the conical intake jet and two-stroke scavenger flows are reviewed. The flow phenomenon near walls are then discussed, with application to heat transfer and hydrocarbon emissions phenomena.

  14. FORMALIZATION OF DIESEL ENGINE OPERATION CONSIDERING THE EVALUATION OF VELOCITY DURING THE COMBUSTION PROCESSES

    Directory of Open Access Journals (Sweden)

    V. P. Litvinenko

    2015-10-01

    Full Text Available Purpose. Under modern conditions the applying methods and design models as well as the evaluation of the operational characteristics of diesel engines do not completely take into consideration the specifics of the combustion processes. In part, such situation is characterized by the complexity of considering of varied by its nature processes that haven’t been completely investigated. In this context it is necessary to find the new methods and models which would provide relatively simple solutions through the use of integrated factors based on the analysis of parameters of diesel engines. Methodology. The proposed algorithms for the estimating of the combustion process in the form of volumetric and linear velocities is based on the well-known parameters of power and mean effective pressure and allows to compare the efficiency of their behavior in various versions of diesel engines. Findings. The author specified that the volumetric / linear velocity ratio is characterized by some strength and depends on the geometric dimensions of the cylinder-piston group. Due to the assumptions it has become possible to consider the operation of a diesel engine as a system comprising: 1 the subsystem that provides the possibility of obtaining the thermal energy; 2 the subsystem providing the thermal energy transformation; 3 the subsystem that provides the necessary diesel engine power depending on terms of combustion of air-fuel mixture. Originality. The author of the paper proposed the indices of volumetric and linear combustion velocity of air-fuel mixture in the engine cylinder, that allow to obtain the comparative value in different modifications taking into account the possible choice of optimum ratio. Practical value. The usage of indices of volumetric and linear velocities of the combustion processes in the engine cylinder combined with a mathematical model will simplify the method of diesels calculating. Parametric indices of the mentioned velocities

  15. Lean-rich axial stage combustion in a can-annular gas turbine engine

    Energy Technology Data Exchange (ETDEWEB)

    Laster, Walter R.; Szedlacsek, Peter

    2016-06-14

    An apparatus and method for lean/rich combustion in a gas turbine engine (10), which includes a combustor (12), a transition (14) and a combustor extender (16) that is positioned between the combustor (12) and the transition (14) to connect the combustor (12) to the transition (14). Openings (18) are formed along an outer surface (20) of the combustor extender (16). The gas turbine (10) also includes a fuel manifold (28) to extend along the outer surface (20) of the combustor extender (16), with fuel nozzles (30) to align with the respective openings (18). A method (200) for axial stage combustion in the gas turbine engine (10) is also presented.

  16. Visualizations of Gas fuel Jet and Combustion Flame on Hydrogen Rotary Engine

    OpenAIRE

    田端, 道彦; 香川, 良二

    2011-01-01

    [Abstract] In this paper, it is a purpose to obtain basic information of a hydrogen jet and combustion flame characteristics of the hydrogen rotary engine. The jet characteristics of the hydrogen gas injector were measured by using the high-speed shadowgraph method. As the result, the jet penetration of the low density gas was weak. The mixing of the direction of the jet axis was disturbed for the low jet pressure. Next, the combustion flame propagation of the hydrogen rotary engine was visua...

  17. Investigation of diesel engine for low exhaust emissions with different combustion chambers

    Directory of Open Access Journals (Sweden)

    Ghodke Pundlik R.

    2015-01-01

    Full Text Available Upcoming stringent Euro-6 emission regulations for passenger vehicle better fuel economy, low cost are the key challenges for engine development. In this paper, 2.2L, multi cylinder diesel engine have been tested for four different piston bowls designed for compression ratio of CR 15.5 to improve in cylinder performance and reduce emissions. These combustion chambers were verified in CFD at two full load points. 14 mode points have been derived using vehicle model run in AVL CRUISE software as per NEDC cycle based on time weightage factor. Base engine with compression ratio CR16.5 for full load performance and 14-mode points on Engine test bench was taken as reference for comparison. The bowl with flat face on bottom corner has shown reduction 25% and 12 % NOx emissions at 1500 and 3750 rpm full load points at same level of Soot emissions. Three piston bowls were tested for full load performance and 14 mode points on engine test bench and combustion chamber ‘C’ has shown improvement in thermal efficiency by 0.8%. Combinations of cooled EGR and combustion chamber ‘C’ with geometrical changes in engine have reduced exhaust NOx, soot and CO emissions by 22%, 9 % and 64 % as compared to base engine at 14 mode points on engine test bench.

  18. Combustion, performance and emissions characteristics of a newly developed CRDI single cylinder diesel engine

    Indian Academy of Sciences (India)

    Avinash Kumar Agarwal; Paras Gupta; Atul Dhar

    2015-09-01

    For improving engine performance, combustion and controlling emissions from compression ignition (CI) engines, common rail direct injection (CRDI) technology offers limitless possibilities by controlling fuel injection parameters such as fuel injection pressure, start of injection (SOI) timing, rate of fuel injection and injection duration. CRDI systems available commercially are quite complex and use a large number of sensors, hardware and analytical circuits, which make them very expensive and unfeasible for cheaper single cylinder engines, typically used in agricultural sector and decentralized power sector. This paper covers experimental investigations of a simpler version of CRDI system developed for a constant-speed, single-cylinder engine. Modifications in the cylinder head for accommodating solenoid injector, designing injector driver circuit and development of high pressure stage controls were some of the engine modification and development tasks undertaken. SOI timing is an important parameter for improving engine's combustion characteristics. SOI timings were varied between 25° and 40° BTDC for investigating engine's performance, emissions and combustion characteristics. Advanced fuel injections showed higher heat release rate (HRR), cylinder pressure and rate of pressure rise (RoPR) because of relatively longer ignition delay experienced. Lowest brake specific fuel consumption (BSFC) was obtained for 34° CA BTDC SOI. Reduction in engine out emissions except NOx was observed for advanced fuel injection timings for this newly developed CRDI system.

  19. Engineering electrical properties of graphene: chemical approaches

    Science.gov (United States)

    Kim, Yong-Jin; Kim, Yuna; Novoselov, Konstantin; Hong, Byung Hee

    2015-12-01

    To ensure the high performance of graphene-based devices, it is necessary to engineer the electrical properties of graphene with enhanced conductivity, controlled work function, opened or closed bandgaps, etc. This can be performed by various non-covalent chemical approaches, including molecular adsorption, substrate-induced doping, polymerization on graphene, deposition of metallic thin films or nanoparticles, etc. In addition, covalent approaches such as the substitution of carbon atoms with boron or nitrogen and the functionalization with hydrogen or fluorine are useful to tune the bandgaps more efficiently, with better uniformity and stability. In this review, representative examples of chemically engineered graphene and its device applications will be reviewed, and remaining challenges will be discussed.

  20. The hierarchical structure of chemical engineering

    Institute of Scientific and Technical Information of China (English)

    Mooson KWAUK

    2007-01-01

    Around the turn of the present century, scholars began to recognize chemical engineering as a complex system, and have been searching for a convenient point of entry for refreshing its knowledge base. From our study of the dynamic structures of dispersed particles in fluidization and the resulting multi-scale method, we have been attempting to extend our findings to structures prevailing in other multiphase systems as well as in the burgeoning industries producing functional materials. Chemical engineering itself is hierarchically structured. Besides structures based on space and time, such hierarchy could be built from ChE history scaled according to science content, or from ChE operation according to the expenditure of manpower and capital investment.

  1. Fuel Chemistry And Combustion Distribution Effects On Rocket Engine Combustion Stability

    Science.gov (United States)

    2015-11-19

    model, the D 2 law rate constant for ideal combustion, k0, of a droplet is dependent on the thermal properties of the fuel and oxidizer and is...remaining increase in the D 2 law regression rate constant is caused by the non- ideal conditions of the experiment. Natural convection is present, as...is the gap-averaged pressure. Considering incompressible gas flow (ρ is constant ), two governing equations can be solved for the pressure in the gap

  2. Analysis of Chemical Reaction Kinetics Behavior of Nitrogen Oxide During Air-staged Combustion in Pulverized Boiler

    Directory of Open Access Journals (Sweden)

    Jun-Xia Zhang

    2016-03-01

    Full Text Available Because the air-staged combustion technology is one of the key technologies with low investment running costs and high emission reduction efficiency for the pulverized boiler, it is important to reveal the chemical reaction kinetics mechanism for developing various technologies of nitrogen oxide reduction emissions. At the present work, a three-dimensional mesh model of the large-scale four corner tangentially fired boiler furnace is established with the GAMBIT pre-processing of the FLUENT software. The partial turbulent premixed and diffusion flame was simulated for the air-staged combustion processing. Parameters distributions for the air-staged and no the air-staged were obtained, including in-furnace flow field, temperature field and nitrogen oxide concentration field. The results show that the air-staged has more regular velocity field, higher velocity of flue gas, higher turbulence intensity and more uniform temperature of flue gas. In addition, a lower negative pressure zone and lower O2 concentration zone is formed in the main combustion zone, which is conducive to the NO of fuel type reduced to N2, enhanced the effect of NOx reduction. Copyright © 2016 BCREC GROUP. All rights reserved Received: 5th November 2015; Revised: 14th January 2016; Accepted: 16th January 2016  How to Cite: Zhang, J.X., Zhang, J.F. (2016. Analysis of Chemical Reaction Kinetics Behavior of Nitrogen Oxide During Air-staged Combustion in Pulverized Boiler. Bulletin of Chemical Reaction Engineering & Catalysis, 11 (1: 100-108. (doi:10.9767/bcrec.11.1.431.100-108 Permalink/DOI: http://dx.doi.org/10.9767/bcrec.11.1.431.100-108

  3. Prediction of Combustion Instability with Detailed Chemical Kinetics

    Science.gov (United States)

    2014-12-01

    ABSTRACT Combustion instability in an unstable single element rocket chamber using methane as the fuel is computationally studied. Effects of the...unstable single element rocket chamber using methane as the fuel is computationally studied. Effects of the kinetics mechanism are examined by...coaxial fuel injector using gaseous methane as fuel. The oxidizer post length of the CVRC can be changed during the experiment to obtain different

  4. Photographic Study of Combustion in a Rocket Engine I : Variation in Combustion of Liquid Oxygen and Gasoline with Seven Methods of Propellant Injection

    Science.gov (United States)

    Bellman, Donald R; Humphrey, Jack C

    1948-01-01

    Motion pictures at camera speeds up to 3000 frames per second were taken of the combustion of liquid oxygen and gasoline in a 100-pound-thrust rocket engine. The engine consisted of thin contour and injection plates clamped between two clear plastic sheets forming a two-dimensional engine with a view of the entire combustion chamber and nozzle. A photographic investigation was made of the effect of seven methods of propellant injection on the uniformity of combustion. From the photographs, it was found that the flame front extended almost to the faces of the injectors with most of the injection methods, all the injection systems resulted in a considerable nonuniformity of combustion, and luminosity rapidly decreased in the divergent part of the nozzle. Pressure vibration records indicated combustion vibrations that approximately corresponded to the resonant frequencies of the length and the thickness of the chamber. The combustion temperature divided by the molecular weight of the combustion gases as determined from the combustion photographs was about 50 to 70 percent of the theoretical value.

  5. An internal combustion engine with interconnected multicylinder arrangement. Verbrennungsmotor mit Mehrzylinderverbund

    Energy Technology Data Exchange (ETDEWEB)

    Mosdell, R.

    1990-08-02

    The invention is dedicated to the kinematic characteristics of multicylinder/multichamber internal combustion engine crank mechanisms and intends to reduce internal energy losses due to mass inertia during combustion energy (impulse) transmission to the piston, connecting rod and crankshaft. This reduction is achieved by modifying the gas exchange control of conventional four-cycle or two-cycle diesel engines, four-cycle or two-cycle spark ignition engines or four-cycle Wankel engines. The ususal successive ignition order of individual cylinders according to the number of cylinders on the crankshaft is replaced by an arrangement of several interconnected cylinders which ignite simultaneously or time-delayed, thus increasing the combustion energy (impulse) and reducing the mass inertia of the piston, connecting rod, crankshaft, disk flywheel and drive components by division. Especially the Wankel engine is expected to profit by the invention's design because of the relatively high mass inertia of all its movable transmission elements and because of higher instantaneous combustion impulses due to doubling, which account for an unproportionately high performance increase.

  6. ENGINEERED BARRIER SYSTEM: PHYSICAL AND CHEMICAL ENVIRONMENT

    Energy Technology Data Exchange (ETDEWEB)

    R. Jarek

    2004-11-23

    The purpose of this report is to describe the evolution of the physical and chemical environmental conditions within the waste emplacement drifts of the repository, including the drip shield and waste package surfaces. The abstraction model is used in the total system performance assessment for the license application (TSPA LA) to assess the performance of the engineered barrier system and the waste form. This report develops and documents a set of these abstraction-level models that describe the engineered barrier system physical and chemical environment. Where possible, these models use information directly from other reports as input, which promotes integration among process models used for TSPA-LA. Specific tasks and activities of modeling the physical and chemical environment are included in ''Technical Work Plan for: Near-Field Environment and Transport In-Drift Geochemistry Model Report Integration'' (BSC 2004 [DIRS 171156], Section 1.2.2). As described in the technical work plan, the development of this report is coordinated with the development of other engineered barrier system reports.

  7. ENGINEERED BARRIER SYSTEM: PHYSICAL AND CHEMICAL ENVIRONMENT

    Energy Technology Data Exchange (ETDEWEB)

    G.H. Nieder-Westermann

    2005-04-07

    The purpose of this report is to describe the evolution of the physical and chemical environmental conditions within the waste emplacement drifts of the repository, including the drip shield and waste package surfaces. The abstraction model is used in the total system performance assessment for the license application (TSPA LA) to assess the performance of the engineered barrier system and the waste form. This report develops and documents a set of these abstraction-level models that describe the engineered barrier system physical and chemical environment. Where possible, these models use information directly from other reports as input, which promotes integration among process models used for TSPA-LA. Specific tasks and activities of modeling the physical and chemical environment are included in ''Technical Work Plan for: Near-Field Environment and Transport In-Drift Geochemistry Model Report Integration'' (BSC 2004 [DIRS 171156], Section 1.2.2). As described in the technical work plan, the development of this report is coordinated with the development of other engineered barrier system reports.

  8. Combustion Dynamics and Control for Ultra Low Emissions in Aircraft Gas-Turbine Engines

    Science.gov (United States)

    DeLaat, John C.

    2011-01-01

    Future aircraft engines must provide ultra-low emissions and high efficiency at low cost while maintaining the reliability and operability of present day engines. The demands for increased performance and decreased emissions have resulted in advanced combustor designs that are critically dependent on efficient fuel/air mixing and lean operation. However, all combustors, but most notably lean-burning low-emissions combustors, are susceptible to combustion instabilities. These instabilities are typically caused by the interaction of the fluctuating heat release of the combustion process with naturally occurring acoustic resonances. These interactions can produce large pressure oscillations within the combustor and can reduce component life and potentially lead to premature mechanical failures. Active Combustion Control which consists of feedback-based control of the fuel-air mixing process can provide an approach to achieving acceptable combustor dynamic behavior while minimizing emissions, and thus can provide flexibility during the combustor design process. The NASA Glenn Active Combustion Control Technology activity aims to demonstrate active control in a realistic environment relevant to aircraft engines by providing experiments tied to aircraft gas turbine combustors. The intent is to allow the technology maturity of active combustion control to advance to eventual demonstration in an engine environment. Work at NASA Glenn has shown that active combustion control, utilizing advanced algorithms working through high frequency fuel actuation, can effectively suppress instabilities in a combustor which emulates the instabilities found in an aircraft gas turbine engine. Current efforts are aimed at extending these active control technologies to advanced ultra-low-emissions combustors such as those employing multi-point lean direct injection.

  9. Research Needs and Impacts in Predictive Simulation for Internal Combustion Engines (PreSICE)

    Energy Technology Data Exchange (ETDEWEB)

    Eckerle, Wayne [Cummins, Inc., Columbus, IN (United States); Rutland, Chris [Univ. of Wisconsin, Madison, WI (United States); Rohlfing, Eric [Dept. of Energy (DOE), Washington DC (United States). Office of Science; Singh, Gurpreet [Dept. of Energy (DOE), Washington DC (United States). Office of Energy Efficiency and Renewable Energy; McIlroy, Andrew [Sandia National Lab. (SNL-CA), Livermore, CA (United States)

    2011-03-03

    This report is based on a SC/EERE Workshop to Identify Research Needs and Impacts in Predictive Simulation for Internal Combustion Engines (PreSICE), held March 3, 2011, to determine strategic focus areas that will accelerate innovation in engine design to meet national goals in transportation efficiency. The U.S. has reached a pivotal moment when pressures of energy security, climate change, and economic competitiveness converge. Oil prices remain volatile and have exceeded $100 per barrel twice in five years. At these prices, the U.S. spends $1 billion per day on imported oil to meet our energy demands. Because the transportation sector accounts for two-thirds of our petroleum use, energy security is deeply entangled with our transportation needs. At the same time, transportation produces one-quarter of the nation’s carbon dioxide output. Increasing the efficiency of internal combustion engines is a technologically proven and cost-effective approach to dramatically improving the fuel economy of the nation’s fleet of vehicles in the near- to mid-term, with the corresponding benefits of reducing our dependence on foreign oil and reducing carbon emissions. Because of their relatively low cost, high performance, and ability to utilize renewable fuels, internal combustion engines—including those in hybrid vehicles—will continue to be critical to our transportation infrastructure for decades. Achievable advances in engine technology can improve the fuel economy of automobiles by over 50% and trucks by over 30%. Achieving these goals will require the transportation sector to compress its product development cycle for cleaner, more efficient engine technologies by 50% while simultaneously exploring innovative design space. Concurrently, fuels will also be evolving, adding another layer of complexity and further highlighting the need for efficient product development cycles. Current design processes, using “build and test” prototype engineering, will not

  10. Chemical Kinetics in Support of Syngas Turbine Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Dryer, Frederick

    2007-07-31

    This document is the final report on an overall program formulated to extend our prior work in developing and validating kinetic models for the CO/hydrogen/oxygen reaction by carefully analyzing the individual and interactive behavior of specific elementary and subsets of elementary reactions at conditions of interest to syngas combustion in gas turbines. A summary of the tasks performed under this work are: 1. Determine experimentally the third body efficiencies in H+O{sub 2}+M = HO{sub 2}+M (R1) for CO{sub 2} and H{sub 2}O. 2. Using published literature data and the results in this program, further develop the present H{sub 2}/O{sub 2}/diluent and CO/H{sub 2}/O{sub 2}/diluent mechanisms for dilution with CO{sub 2}, H{sub 2}O and N{sub 2} through comparisons with new experimental validation targets for H{sub 2}-CO-O{sub 2}-N{sub 2} reaction kinetics in the presence of significant diluent fractions of CO{sub 2} and/or H{sub 2}O, at high pressures. (task amplified to especially address ignition delay issues, see below). 3. Analyze and demonstrate issues related to NOx interactions with syngas combustion chemistry (task amplified to include interactions of iron pentacarbonyl with syngas combustion chemistry, see below). 4. Publish results, including updated syngas kinetic model. Results are summarized in this document and its appendices. Three archival papers which contain a majority of the research results have appeared. Those results not published elsewhere are highlighted here, and will appear as part of future publications. Portions of the work appearing in the above publications were also supported in part by the Department of Energy under Grant No. DE-FG02-86ER-13503. As a result of and during the research under the present contract, we became aware of other reported results that revealed substantial differences between experimental characterizations of ignition delays for syngas mixtures and ignition delay predictions based upon homogenous kinetic modeling. We

  11. Effects of ethanol on combustion and emissions of a gasoline engine operating with different combustion modes

    OpenAIRE

    Ojapah, MM; Zhao, H.; Zhang, Y.

    2016-01-01

    The introduction of fuel economy and CO2 emission legislations for passenger cars in many countries and regions has spurred the research and development of more efficient gasoline engines. The pumping loss at part-load operations is a major factor for the higher fuel consumption of spark ignition (SI) gasoline engines than the diesel engines. Various approaches have been identified to reduce the pumping loss at part-load operations, leading to improved fuel economy, including Early Intake Val...

  12. A statistical model for combustion resonance from a DI diesel engine with applications

    Science.gov (United States)

    Bodisco, Timothy; Low Choy, Samantha; Masri, Assaad; Brown, Richard J.

    2015-08-01

    Introduced in this paper is a Bayesian model for isolating the resonant frequency from combustion chamber resonance. The model shown in this paper focused on characterising the initial rise in the resonant frequency to investigate the rise of in-cylinder bulk temperature associated with combustion. By resolving the model parameters, it is possible to determine: the start of pre-mixed combustion, the start of diffusion combustion, the initial resonant frequency, the resonant frequency as a function of crank angle, the in-cylinder bulk temperature as a function of crank angle and the trapped mass as a function of crank angle. The Bayesian method allows for individual cycles to be examined without cycle-averaging-allowing inter-cycle variability studies. Results are shown for a turbo-charged, common-rail compression ignition engine run at 2000 rpm and full load.

  13. The railplug: Development of a new ignitor for internal combustion engines. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Matthews, R.D.; Nichols, S.P.; Weldon, W.F.

    1994-11-29

    A three year investigation of a new type of ignitor for internal combustion engines has been performed using funds from the Advanced Energy Projects Program of The Basic Energy Sciences Division of the U.S. Department of Energy and with matching funding from Research Applications, Inc. This project was a spin-off of {open_quotes}Star Wars{close_quotes} defense technology, specifically the railgun. The {open_quotes}railplug{close_quotes} is a miniaturized railgun which produces a high velocity plume of plasma that is injected into the combustion chamber of an engine. Unlike other types of alternative ignitors, such as plasma jet ignitors, electromagnetic forces enhance the acceleration of the plasma generated by a railplug. Thus, for a railplug, the combined effects of electromagnetic and thermodynamic forces drive the plasma into the combustion chamber. Several engine operating conditions or configurations can be identified that traditionally present ignition problems, and might benefit from enhanced ignition systems. One of these is ultra-lean combustion in spark ignition (SI) engines. This concept has the potential for lowering emissions of NOx while simultaneously improving thermal efficiency. Unfortunately, current lean burn engines cannot be operated sufficiently lean before ignition related problems are encountered to offer any benefits. High EGR engines have similar potential for emissions improvement, but also experience similar ignition problems, particularly at idle. Other potential applications include diesel cold start, alcohol and dual fuel engines, and high altitude relight of gas turbines. The railplug may find application for any of the above. This project focused on three of these potential applications: lean burn SI engines, high EGR SI engines, and diesel cold start.

  14. DOE Project 18546, AOP Task 1.1, Fuel Effects on Advanced Combustion Engines

    Energy Technology Data Exchange (ETDEWEB)

    Bunting, Bruce G [ORNL; Bunce, Michael [ORNL

    2012-01-01

    Research in 2011 was focused on diesel range fuels and diesel combustion and fuels evaluated in 2011 included a series of oxygenated biofuels fuels from University of Maine, oxygenated fuel compounds representing materials which could be made from sewage, oxygenated marine diesel fuels for low emissions, and a new series of FACE fuel surrogates and FACE fuels with detailed exhaust chemistry and particulate size measurements. Fuels obtained in late 2011, which will be evaluated in 2012, include a series of oil shale derived fuels from PNNL, green diesel fuel (hydrotreated vegetable oil) from UOP, University of Maine cellulosic biofuel (levulene), and pyrolysis derived fuels from UOP pyrolysis oil, upgraded at University of Georgia. We were able to demonstrate, through a project with University of Wisconsin, that a hybrid strategy for fuel surrogates provided both accurate and rapid CFD combustion modeling for diesel HCCI. In this strategy, high molecular weight compounds are used to more accurately represent physical processes and smaller molecular weight compounds are used for chemistry to speed chemical calculations. We conducted a small collaboration with sp3H, a French company developing an on-board fuel quality sensor based on near infrared analysis to determine how to use fuel property and chemistry information for engine control. We were able to show that selected outputs from the sensor correlated to both fuel properties and to engine performance. This collaboration leveraged our past statistical analysis work and further work will be done as opportunity permits. We conducted blending experiments to determine characteristics of ethanol blends based on the gasoline characteristics used for blending. Results indicate that much of the octane benefits gained by high level ethanol blending can be negated by use of low octane gasoline blend stocks, as allowed by ASTM D5798. This may limit ability to optimize engines for improved efficiency with ethanol fuels

  15. Experimental study of hydrogen as a fuel additive in internal combustion engines

    Energy Technology Data Exchange (ETDEWEB)

    Saanum, Inge

    2008-07-01

    Combustion of hydrocarbons in internal combustion engines results in emissions that can be harmful both to human health and to the environment. Although the engine technology is improving, the emissions of NO{sub x}, PM and UHC are still challenging. Besides, the overall consumption of fossil fuel and hence the emissions of CO{sub 2} are increasing because of the increasing number of vehicles. This has lead to a focus on finding alternative fuels and alternative technologies that may result in lower emissions of harmful gases and lower CO{sub 2} emissions. This thesis treats various topics that are relevant when using blends of fuels in different internal combustion engine technologies, with a particular focus on using hydrogen as a fuel additive. The topics addressed are especially the ones that impact the environment, such as emissions of harmful gases and thermal efficiency (fuel consumption). The thesis is based on experimental work performed at four different test rigs: 1. A dynamic combustion rig with optical access to the combustion chamber where spark ignited premixed combustion could be studied by means of a Schlieren optical setup and a high speed video camera. 2. A spark ignition natural gas engine rig with an optional exhaust gas recycling system. 3. A 1-cylinder diesel engine prepared for homogeneous charge compression ignition combustion. 4. A 6-cylinder standard diesel engine The engine rigs were equipped with cylinder pressure sensors, engine dynamometers, exhaust gas analyzers etc. to enable analyses of the effects of different fuels. The effect of hydrogen blended with methane and natural gas in spark ignited premixed combustion was investigated in the dynamic combustion rig and in a natural gas engine. In the dynamic combustion rig, the effect of hydrogen added to methane on the flame speed and the flame structure was investigated at elevated pressure and temperature. A considerable increase in the flame speed was observed when adding 30 vol

  16. Engineering cyanobacteria for fuels and chemicals production.

    Science.gov (United States)

    Zhou, Jie; Li, Yin

    2010-03-01

    The world's energy and global warming crises call for sustainable, renewable, carbon-neutral alternatives to replace fossil fuel resources. Currently, most biofuels are produced from agricultural crops and residues, which lead to concerns about food security and land shortage. Compared to the current biofuel production system, cyanobacteria, as autotrophic prokaryotes, do not require arable land and can grow to high densities by efficiently using solar energy, CO(2), water, and inorganic nutrients. Moreover, powerful genetic techniques of cyanobacteria have been developed. For these reasons, cyanobacteria, which carry out oxygenic photosynthesis, are attractive hosts for production of fuels and chemicals. Recently, several chemicals including ethanol, isobutanol and isoprene have been produced by engineered cyanobacteria directly using solar energy, CO(2), and water. Cyanobacterium is therefore a potential novel cell factory for fuels and chemicals production to address global energy security and climate change issues.

  17. Combustion and emissions of the diesel engine using bio-diesel fuel

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The combustion and heat release of engines using diesel fuel and bio-diesel fuel have been investigated.The results illustrate that the combustion happens in advance and the ignition delay period is shortened.The initial heat release peak declines a little,the corresponding crankshaft angle changes in advance,and the combustion duration is prolonged.The economic performance and emission features of diesel engines using diesel fuel and bio-diesel fuel are compared.The results also show that the specific fuel consumption of bio-diesel increases by about 12% .The emissions,such as CO,HC,and particulate matter decrease remarkably whereas NOx increases a little.

  18. Modeling of scalar dissipation rates in flamelet models for low temperature combustion engine simulations

    CERN Document Server

    Gupta, Saurabh; Pal, Pinaki; Im, Hong G

    2014-01-01

    The flamelet approach offers a viable framework for combustion modeling of homogeneous charge compression ignition (HCCI) engines under stratified mixture conditions. Scalar dissipation rate acts as a key parameter in flamelet-based combustion models which connects the physical mixing space to the reactive space. The aim of this paper is to gain fundamental insights into turbulent mixing in low temperature combustion (LTC) engines and investigate the modeling of scalar dissipation rate. Three direct numerical simulation (DNS) test cases of two-dimensional turbulent auto-ignition of a hydrogen-air mixture with different correlations of temperature and mixture fraction are considered, which are representative of different ignition regimes. The existing models of mean and conditional scalar dissipation rates, and probability density functions (PDFs) of mixture fraction and total enthalpy are a priori validated against the DNS data.

  19. Efficiency of a new internal combustion engine concept with variable piston motion

    Directory of Open Access Journals (Sweden)

    Dorić Jovan Ž.

    2014-01-01

    Full Text Available This paper presents simulation of working process in a new IC engine concept. The main feature of this new IC engine concept is the realization of variable movement of the piston. With this unconventional piston movement it is easy to provide variable compression ratio, variable displacement and combustion during constant volume. These advantages over standard piston mechanism are achieved through synthesis of the two pairs of non-circular gears. Presented mechanism is designed to obtain a specific motion law which provides better fuel consumption of IC engines. For this paper Ricardo/WAVE software was used, which provides a fully integrated treatment of time-dependent fluid dynamics and thermodynamics by means of onedimensional formulation. The results obtained herein include the efficiency characteristic of this new heat engine concept. The results show that combustion during constant volume, variable compression ratio and variable displacement have significant impact on improvement of fuel consumption.

  20. Effect of Fuel Types on Combustion Characteristics and Performance of a Four Stroke IC Engine

    Directory of Open Access Journals (Sweden)

    Mrs. Rana Ali Hussein,

    2014-04-01

    Full Text Available In this study, the effect of Gasoline, Ethanol, Gasohol E10, and Kerosene on the performance and combustion characteristics of a spark ignition (SI engine were investigated. In the experiment, the internal combustion (IC engine includes one cylinder, two valves, and four stroke spark ignition. Performance tests were carried out for specific fuel consumption, brake specific fuel consumption, power developed, corrosion rate, and carbon dioxide (CO2 and carbon monoxide (CO emissions. The measurements were conducted under various engine speeds ranging from 1500 to 4500 rpm. The experimental results showed that the performance of engine was improved with the use of gasoline and gasohol E10 in comparison with the Ethanol and Kerosene. The concentrations of CO2 and CO were presented and compared for all type of fuel examined.

  1. Experimental study of hydrogen as a fuel additive in internal combustion engines

    Energy Technology Data Exchange (ETDEWEB)

    Saanum, Inge

    2008-07-01

    Combustion of hydrocarbons in internal combustion engines results in emissions that can be harmful both to human health and to the environment. Although the engine technology is improving, the emissions of NO{sub x}, PM and UHC are still challenging. Besides, the overall consumption of fossil fuel and hence the emissions of CO{sub 2} are increasing because of the increasing number of vehicles. This has lead to a focus on finding alternative fuels and alternative technologies that may result in lower emissions of harmful gases and lower CO{sub 2} emissions. This thesis treats various topics that are relevant when using blends of fuels in different internal combustion engine technologies, with a particular focus on using hydrogen as a fuel additive. The topics addressed are especially the ones that impact the environment, such as emissions of harmful gases and thermal efficiency (fuel consumption). The thesis is based on experimental work performed at four different test rigs: 1. A dynamic combustion rig with optical access to the combustion chamber where spark ignited premixed combustion could be studied by means of a Schlieren optical setup and a high speed video camera. 2. A spark ignition natural gas engine rig with an optional exhaust gas recycling system. 3. A 1-cylinder diesel engine prepared for homogeneous charge compression ignition combustion. 4. A 6-cylinder standard diesel engine The engine rigs were equipped with cylinder pressure sensors, engine dynamometers, exhaust gas analyzers etc. to enable analyses of the effects of different fuels. The effect of hydrogen blended with methane and natural gas in spark ignited premixed combustion was investigated in the dynamic combustion rig and in a natural gas engine. In the dynamic combustion rig, the effect of hydrogen added to methane on the flame speed and the flame structure was investigated at elevated pressure and temperature. A considerable increase in the flame speed was observed when adding 30 vol

  2. Effect of hydrogen-diesel combustion on the performance and combustion parameters of a dual fuelled diesel engine

    Energy Technology Data Exchange (ETDEWEB)

    Bose, P.K.; Banerjee, Rahul; Deb, Madhujit [Mechanical Engineering Department, National Institute of Technology, Agartala, Tripura-799055 (India)

    2013-07-01

    Petroleum crude is expected to remain main source of transport fuels at least for the next 20 to 30 years. The petroleum crude reserves however, are declining and consumption of transport fuels particularly in the developing countries is increasing at high rates. Severe shortage of liquid fuels derived from petroleum may be faced in the second half of this century. In this paper, experiments are performed in a fur stroke, single cylinder, compression ignition diesel engine with dual fuel mode. Diesel and hydrogen are used as pilot liquid and primary gaseous fuel, respectively. The objective of this study is to find out the effects on combustion and performance parameters observed at diesel hydrogen fuel mixture for all the different loadings (2kg,4kg,6kg,8kg,10kg and 12kg) in the engine.

  3. Regenerable mixed copper-iron-inert support oxygen carriers for solid fuel chemical looping combustion process

    Energy Technology Data Exchange (ETDEWEB)

    Siriwardane, Ranjani V.; Tian, Hanjing

    2016-12-20

    The disclosure provides an oxygen carrier for a chemical looping cycle, such as the chemical looping combustion of solid carbonaceous fuels, such as coal, coke, coal and biomass char, and the like. The oxygen carrier is comprised of at least 24 weight % (wt %) CuO, at least 10 wt % Fe2O3, and an inert support, and is typically a calcine. The oxygen carrier exhibits a CuO crystalline structure and an absence of iron oxide crystalline structures under XRD crystallography, and provides an improved and sustained combustion reactivity in the temperature range of 600.degree. C.-1000.degree. C. particularly for solid fuels such as carbon and coal.

  4. Performance and analysis of a 4-stroke multi-cylinder gasoline engine with CAI combustion

    OpenAIRE

    Zhao, H.; Li, J; Ma, T.; Ladommatos, N

    2002-01-01

    Copyright © 2002 SAE International. This paper is posted on this site with permission from SAE International. Further use of this paper is not permitted without permission from SAE Controlled Auto-Ignition (CAI) combustion was realised in a production type 4-stroke 4-cylinder gasoline engine without intake charge heating or increasing compression ratio. The CAI engine operation was achieved using substantially standard components modified only in camshafts to restrict the gas exchange proc...

  5. Conflict between internal combustion engine and thermoelectric generator during waste heat recovery in cars

    Science.gov (United States)

    Korzhuev, M. A.

    2011-02-01

    It is shown that an internal combustion engine and a thermoelectric generator (TEG) arranged on the exhaust pipe of this engine come into the conflict of thermal machines that is related to using the same energy resource. The conflict grows with increasing useful electric power W e of the TEG, which leads to the limitation of both the maximum TEG output power ( W {e/max}) and the possibility of waste heat recovery in cars.

  6. Piston ring lubrication and hydrocarbon emissions from internal combustion engines

    Energy Technology Data Exchange (ETDEWEB)

    Froelund, K.

    1997-11-01

    Is it the intention with this project to improve the existing hydrocarbon emission model at the Institute by combining it with a model for predicting the piston ring lubrication. The piston ring lubrication model should be experimentally verified to ensure the validity of the model. The following items were the objectives of the current study: Develop a piston ring lubrication model. This implies the development of a ring-pack gas flow model; Examine the response of the piston ring lubrication model to changing engineer conditions. Especially, it would be interesting to look at the engine warm-up phase since this is the phase where the engine-out emissions are highest and where the commonly used three way catalyst is not capable of converting the engine-out emissions, thereby leading the engine-out emissions directly out in to the environment with the exhaust gases; In order to verify the piston ring lubrication model the lubricant distribution on the cylinder liner should be investigated experimentally. Here again it would be of great interesting to look at the engine warm-up phase; The piston ring lubrication model should be adjusted for application together with the new hydrocarbon emission model for SI-engines at the Institute in order to increase the accuracy of the latter; The piston ring lubrication model could be used for describing the transport of PAH`s in diesel engines. (EG)

  7. Measuring Scaling Effects in Small Two-Stroke Internal Combustion Engines

    Science.gov (United States)

    2014-06-20

    equivalence ratio. If the enthalpy of products is the same as the enthalpy of reactants in a combustion reaction , the resultant temperature change would yield...15 Figure 6: Cetane number versus MON for common ICE hydrocarbon fuels [10] ........... 19...an IC engine burning hydrocarbon fuels. Although technological advancements have allowed great improvements in the capability of the motor and

  8. Auto-Ignition and Heat Release Correlations for Controlled Auto-Ignition Combustion in Gasoline Engines

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Auto-ignition and heat release correlations for controlled auto-ignition (CAI) combustion were derived from extensive in-cylinder pressure data of a four-stroke gasoline engine operating in CAI combustion mode. Abundant experiments were carried out under a wide range of air/fuel ratio,speed and residual gas fraction to ensure that the combustion correlations can be used in the entire CAI engine operation range. Furthermore, a more accurate method to compute the residual gas fraction was proposed by calculating the working fluid temperature at the exhaust valve close timing in the experiments. The heat release correlation was described in two parts, one is for the first slower heat release process at low temperature, and the other is for the second faster heat release process at high temperature. Finally the heat release correlation was evaluated on the single cylinder gasoline engine running with CAI combustion by comparing the experimental data with the 1-D engine simulation results obtained with the aid of the GT-Power simulation program. The results show that the predicted loads and ignition timings match closely with the measurements.

  9. Combustion Chamber Deposits and PAH Formation in SI Engines Fueled by Producer Gas from Biomass Gasification

    DEFF Research Database (Denmark)

    Ahrenfeldt, Jesper; Henriksen, Ulrik Birk; Schramm, Jesper

    2003-01-01

    Investigations were made concerning the formation of combustion chamber deposits (CCD) in SI gas engines fueled by producer gas. The main objective was to determine and characterise CCD and PAH formation caused by the presence of the light tar compounds phenol and guaiacol in producer gas from an...

  10. Experimental validation of extended NO and soot model for advanced HD diesel engine combustion

    NARCIS (Netherlands)

    Seykens, X.L.J.; Baert, R.S.G.; Somers, L.M.T.; Willems, F.P.T.

    2009-01-01

    A computationally efficient engine model is developed based on an extended NO emission model and state-of-the-art soot model. The model predicts exhaust NO and soot emission for both conventional and advanced, high-EGR (up to 50%), heavy-duty DI diesel combustion. Modeling activities have aimed at l

  11. Evaluation of the Migrating Combustion Chamber (MCC) Engine

    Science.gov (United States)

    1993-01-01

    REPORT DOCUMENTATION PAGE OHINo. 0704-018 Pubk repatng burden bv hs cBig da inimmaion is wabdd lo aage 1 hour p. e .r wkdud toor Isen kN imo.ng ismucm...2. REPORT DATE 3. REPORT TYPE AND DATES COVERED I January 1993 Final 4. TITLE AND SUBTITLE 5. FUNDING NUMBERS Evaluation of the Migrating Combustion...Data Energy Balance Data Point Date Torque Speed Power Air Flow T1 T2 Delta T(*K) Number (oz-in) (rpm) (hp) (CFM) (IF) (OF) 23-Aug 1 3470 0.004 165 82

  12. Rate-Controlled Constrained-Equilibrium Theory Applied to the Expansion of Combustion Products in the Power Stroke of an Internal Combustion Engine

    Directory of Open Access Journals (Sweden)

    Hameed Metghalchi

    2009-03-01

    Full Text Available Rate-controlled constrained-equilibrium method, firmly based on the second law of thermodynamics, is applied to the expansion of combustion products of methane during the power stroke of an internal combustion engine. The constraints used in this study are the elemental oxygen, hydrogen, carbon and nitrogen together with other four dynamic constraints of total number of moles, moles of DCO (CO+HCO, moles of free valence and moles of free oxygen. Since at chemical equilibrium, the mixture composition is dominated by H/O, CO/CO2, and a few other carbon-containing species, almost independent of the fuel molecule, the set results in accurate predictions of the kinetic effects observed in all H/O and CO/CO2 compounds and temperature history. It is shown that the constrained-equilibrium predictions of all the species composed of the specified atomic elements can be obtained independent of a kinetic path, provided their Gibbs free energies are known.

  13. Internal combustion engines for alcohol motor fuels: a compilation of background technical information

    Energy Technology Data Exchange (ETDEWEB)

    Blaser, Richard

    1980-11-01

    This compilation, a draft training manual containing technical background information on internal combustion engines and alcohol motor fuel technologies, is presented in 3 parts. The first is a compilation of facts from the state of the art on internal combustion engine fuels and their characteristics and requisites and provides an overview of fuel sources, fuels technology and future projections for availability and alternatives. Part two compiles facts about alcohol chemistry, alcohol identification, production, and use, examines ethanol as spirit and as fuel, and provides an overview of modern evaluation of alcohols as motor fuels and of the characteristics of alcohol fuels. The final section compiles cross references on the handling and combustion of fuels for I.C. engines, presents basic evaluations of events leading to the use of alcohols as motor fuels, reviews current applications of alcohols as motor fuels, describes the formulation of alcohol fuels for engines and engine and fuel handling hardware modifications for using alcohol fuels, and introduces the multifuel engines concept. (LCL)

  14. A University Consortium on Low Temperature Combustion for High Efficiency, Ultra-Low Emission Engines

    Energy Technology Data Exchange (ETDEWEB)

    Assanis, Dennis N. [Univ. of Michigan, Ann Arbor, MI (United States); Atreya, Arvind [Univ. of Michigan, Ann Arbor, MI (United States); Chen, Jyh-Yuan [Univ. of California, Berkeley, CA (United States); Cheng, Wai K. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Dibble, Robert W. [Univ. of California, Berkeley, CA (United States); Edwards, Chris [Stanford Univ., CA (United States); Filipi, Zoran S. [Univ. of Michigan, Ann Arbor, MI (United States); Gerdes, Christian [Stanford Univ., CA (United States); Im, Hong [Univ. of Michigan, Ann Arbor, MI (United States); Lavoie, George A. [Univ. of Michigan, Ann Arbor, MI (United States); Wooldridge, Margaret S. [Univ. of Michigan, Ann Arbor, MI (United States)

    2009-12-31

    The objective of the University consortium was to investigate the fundamental processes that determine the practical boundaries of Low Temperature Combustion (LTC) engines and develop methods to extend those boundaries to improve the fuel economy of these engines, while operating with ultra low emissions. This work involved studies of thermal effects, thermal transients and engine management, internal mixing and stratification, and direct injection strategies for affecting combustion stability. This work also examined spark-assisted Homogenous Charge Compression Ignition (HCCI) and exhaust after-treatment so as to extend the range and maximize the benefit of Homogenous Charge Compression Ignition (HCCI)/ Partially Premixed Compression Ignition (PPCI) operation. In summary the overall goals were; Investigate the fundamental processes that determine the practical boundaries of Low Temperature Combustion (LTC) engines; Develop methods to extend LTC boundaries to improve the fuel economy of HCCI engines fueled on gasoline and alternative blends, while operating with ultra low emissions; and Investigate alternate fuels, ignition and after-treatment for LTC and Partially Premixed compression Ignition (PPCI) engines.

  15. Control Scheme Formulation for the Production of Hydrogen on Demand to Feed an Internal Combustion Engine

    Directory of Open Access Journals (Sweden)

    Jarniel García Morales

    2016-12-01

    Full Text Available In this work, a control strategy is presented to produce hydrogen on demand to feed an internal combustion (IC engine. For this purpose, the modeling of the IC engine fueled by gasoline blended with 10 % v/v of anhydrous ethanol (E10 and hydrogen as an additive is developed. It is considered that the hydrogen gas is produced according to the IC engine demand, and that the hydrogen gas is obtained by an alkaline electrolyzer. The gasoline–ethanol blend added into the combustion chamber is determined according to the stoichiometric ratio and the production of hydrogen gas is regulated by a proportional and integral controller (P.I.. The controller reference is varying according to the mass flow air induced into the cylinder, in order to ensure an adequate production of hydrogen gas for any operating condition of the IC engine. The main contribution of this work is the control scheme developed, through simulation, in order to produce hydrogen on demand for any operating point of an internal combustion engine fueled by an E10 blend. The simulation results showed that the use of hydrogen gas as an additive in an E10 blend decreases the E10 fuel consumption 23 % on average, and the thermal efficiency is increased approximately 2.13 % , without brake power loss in the IC engine.

  16. The realization and analysis of a new thermodynamic cycle for internal combustion engine

    Directory of Open Access Journals (Sweden)

    Dorić Jovan Ž.

    2011-01-01

    Full Text Available This paper presents description and thermodynamic analysis of a new thermodynamic cycle. Realization of this new cycle is possible to achieve with valveless internal combustion engine with more complete expansion. The main purpose of this new IC engine is to increase engines’ thermal efficiency. The engine was designed so that the thermodynamic changes of the working fluid are different than in conventional engines. Specific differences are reflected in a more complete expansion of the working fluid (the expansion stroke is larger than compression stroke, valveless gas flowing and complete discharge of residual combustion products from the combustion chamber. In this concept, the movement of the piston is different than in conventional piston mechanisms. The results obtained herein include the efficiency characteristics of irreversible reciprocating new engine cycle which is very similar to Miller cycle. The results show that with this thermodynamic cycle engine has higher efficiency than with the standard Otto cycle. In this article, the patent application material under number 2008/607 at the Intellectual Property Office of the Republic of Serbia was used.

  17. System and method for conditioning intake air to an internal combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Sellnau, Mark C.

    2015-08-04

    A system for conditioning the intake air to an internal combustion engine includes a means to boost the pressure of the intake air to the engine and a liquid cooled charge air cooler disposed between the output of the boost means and the charge air intake of the engine. Valves in the coolant system can be actuated so as to define a first configuration in which engine cooling is performed by coolant circulating in a first coolant loop at one temperature, and charge air cooling is performed by coolant flowing in a second coolant loop at a lower temperature. The valves can be actuated so as to define a second configuration in which coolant that has flowed through the engine can be routed through the charge air cooler. The temperature of intake air to the engine can be controlled over a wide range of engine operation.

  18. Modelling cycle to cycle variations in an SI engine with detailed chemical kinetics

    Energy Technology Data Exchange (ETDEWEB)

    Etheridge, Jonathan; Mosbach, Sebastian; Kraft, Markus [Department of Chemical Engineering and Biotechnology, University of Cambridge (United Kingdom); Wu, Hao; Collings, Nick [Department of Engineering, University of Cambridge (United Kingdom)

    2011-01-15

    This paper presents experimental results and a new computational model that investigate cycle to cycle variations (CCV) in a spark ignition (SI) engine. An established stochastic reactor model (SRM) previously used to examine homogeneous charge compression ignition (HCCI) combustion has been extended by spark initiation, flame propagation and flame termination sub-models in order to simulate combustion in SI engines. The model contains a detailed chemical mechanism but relatively short computation times are achieved. The flame front is assumed to be spherical and centred at the spark location, and a pent roof and piston bowl geometry are accounted for. The model is validated by simulating the pressure profile and emissions from an iso-octane fuelled single cylinder research engine that showed low CCV. The effects of key parameters are investigated. Experimental results that show cycle to cycle fluctuations in a four-cylinder naturally aspirated gasoline fuelled SI engine are presented. The model is then coupled with GT-Power, a one-dimensional engine simulation tool, which is used to simulate the breathing events during a multi-cycle simulation. This allows an investigation of the cyclic fluctuations in peak pressure. The source and magnitude of nitric oxide (NO) emissions produced by different cycles are then investigated. It was found that faster burning cycles result in increased NO emissions compared with cycles that have a slower rate of combustion and that more is produced in the early stages of combustion compared with later in the cycle. The majority of NO was produced via the thermal mechanism just after combustion begins. (author)

  19. Experimental Investigation on Space-dispersed Double-wall Jet Combustion System for DI Diesel Engine

    Institute of Scientific and Technical Information of China (English)

    郭鹏江; 高希彦

    2012-01-01

    A space-dispersed double-wall jet combustion system was developed by adopting the wall-guiding spray method and the stratification theory.The experimental test was carried out to optimize the structural parameters of the diesel-engine combustion system,including chamber structure,swirl ratio of cylinder head,included angle of jet orifice,number and diameter of jet orifice,fuel injection pressure and timing.The effect of double-wall jet combustion system on combustion and engine performance was tested to obtain the best performance indexes,and the double-wall jet combustion system was compared to the prototype.The results show that NOx is reduced from 712 PPm to 487 PPm at 2 100 r/min,and from 593 PPm to 369 PPm at 3 000 r/min,which are reduced by 31.6% and 37.7%,respectively.The smoke intensity was reduced form 3.67 BSU to 2.1 BSU,and the oil consumption was reduced from 240.5 g/(kW·h) to 225.4 g/(kW·h),which was decreased by 6.3% at low speed.The pressure in the cylinder was obviously reduced from 115 bar to 108 bar,which was reduced by 6%.

  20. Thermal radiation of heterogeneous combustion products in the model rocket engine plume

    Science.gov (United States)

    Kuzmin, V. A.; Maratkanova, E. I.; Zagray, I. A.; Rukavishnikova, R. V.

    2015-05-01

    The work presents a method of complex investigation of thermal radiation emitted by heterogeneous combustion products in the model rocket engine plume. Realization of the method has allowed us to obtain full information on the results in all stages of calculations. Dependence of the optical properties (complex refractive index), the radiation characteristics (coefficients and cross sections) and emission characteristics (flux densities, emissivity factors) of the main determining factors and parameters was analyzed. It was found by the method of computational experiment that the presence of the gaseous phase in the combustion products causes a strongly marked selectivity of emission, due to which the use of gray approximation in the calculation of thermal radiation is unnecessary. The influence of the optical properties, mass fraction, the function of particle size distribution, and the temperature of combustion products on thermal radiation in the model rocket engine plume was investigated. The role of "spotlight" effect-increasing the amount of energy of emission exhaust combustion products due to scattering by condensate particles radiation from the combustion chamber-was established quantitatively.

  1. Effects of ambient oxygen concentration on biodiesel and diesel spray combustion under simulated engine conditions

    KAUST Repository

    Zhang, Ji

    2013-08-01

    This study investigates the effect of ambient oxygen concentration on biodiesel and diesel spray combustion under simulated compression-ignition engine conditions in a constant-volume chamber. The apparent heat release rate (AHRR) is calculated based on the measured pressure. High-speed imaging of OH* chemiluminescence and natural luminosity (NL) is employed to visualize the combustion process. Temporally and spatially resolved NL and OH* contour plots are obtained. The result indicates that AHRR depends monotonically on the ambient oxygen concentration for both fuels. A lower oxygen concentration yields a slower AHRR increase rate, a lower peak AHRR value, but a higher AHRR value during the burn-out stage when compared with higher ambient oxygen concentration conditions. OH* chemiluminescence and NL contours indicate that biodiesel may experience a longer premixed-combustion duration. The 18% ambient O2 condition works better for biodiesel than diesel in reducing soot luminosity. With 12% O2, diesel combustion is significantly degraded. However, both fuels experience low temperature combustion at 10% O2. These results may imply that biodiesel is able to achieve the desired lower soot production under a moderate oxygen level with higher combustion efficiency, while diesel needs to be burned under very low ambient oxygen concentration for low soot production. © 2013 Elsevier Ltd.

  2. Trends of Syngas as a Fuel in Internal Combustion Engines

    Directory of Open Access Journals (Sweden)

    Ftwi Yohaness Hagos

    2014-01-01

    Full Text Available Syngas from biomass and solid waste is a carbon-neutral fuel believed to be a promising fuel for future engines. It was widely used for spark-ignition engines in the WWII era before being replaced with gasoline. In this paper, the technological development, success, and challenges for application of syngas in power generating plants, the trends of engine technologies, and the potential of this fuel in the current engine technology are highlighted. Products of gasification vary with the variation of input parameters. Therefore, three different syngases selected from the two major gasification product categories are used as case studies. Their fuel properties are compared to those of CNG and hydrogen and the effects on the performance and emissions are studied. Syngases have very low stoichiometric air-fuel ratio; as a result they are not suitable for stoichiometric application. Besides, syngases have higher laminar flame speed as compared to CNG. Therefore, stratification under lean operation should be used in order to keep their performance and emissions of NOx comparable to CNG counterpart. However, late injection stratification leads to injection duration limitation leading to restriction of output power and torque. Therefore, proper optimization of major engine variables should be done in the current engine technology.

  3. Fluid flow for chemical and process engineers

    CERN Document Server

    Holland, F

    1995-01-01

    This major new edition of a popular undergraduate text covers topics of interest to chemical engineers taking courses on fluid flow. These topics include non-Newtonian flow, gas-liquid two-phase flow, pumping and mixing. It expands on the explanations of principles given in the first edition and is more self-contained. Two strong features of the first edition were the extensive derivation of equations and worked examples to illustrate calculation procedures. These have been retained. A new extended introductory chapter has been provided to give the student a thorough basis to understand the methods covered in subsequent chapters.

  4. Biofuels combustion.

    Science.gov (United States)

    Westbrook, Charles K

    2013-01-01

    This review describes major features of current research in renewable fuels derived from plants and from fatty acids. Recent and ongoing fundamental studies of biofuel molecular structure, oxidation reactions, and biofuel chemical properties are reviewed, in addition to combustion applications of biofuels in the major types of engines in which biofuels are used. Biofuels and their combustion are compared with combustion features of conventional petroleum-based fuels. Two main classes of biofuels are described, those consisting of small, primarily alcohol, fuels (particularly ethanol, n-butanol, and iso-pentanol) that are used primarily to replace or supplement gasoline and those derived from fatty acids and used primarily to replace or supplement conventional diesel fuels. Research efforts on so-called second- and third-generation biofuels are discussed briefly.

  5. Design of a single cylinder optical access to the combustion engine Scania D12

    Energy Technology Data Exchange (ETDEWEB)

    Fuchs, Juergen

    2000-11-01

    In this work a maximum optical access to a diesel engine is developed. The combustion-process in the engine should be representative to the one in a standard engine, so the geometry of the combustion chamber is modified as little as possible. A Scania single cylinder, 2-litre engine was subjected to modifications allowing the optical access. Solutions to these problems are obtained by using the method of Product-Development, mainly based on the literature by Prof Dr.-Ing. Birkhofer at the Technical University of Darmstadt, Germany. An optical engine design of the Bowditch type was the chosen main working principle. This engine contains an extended cylinder, partly made of glass, a glass piston-crown and a mirror placed inside the extended piston. The laser sheet is led into the combustion chamber through the glass part of the cylinder, then gets reflected inside the combustion chamber and is led through the glass piston crown and via the mirror out of the engine. A redesign of the valve-train, using extended push-rods, is necessary. The demand to examine the combustion at Top-Dead-Centre (TDC) and the necessity of supporting the glass, give the reasons to do work on the cylinder head. This in return brings sealing problems, which have been solved. Another problem that occurs with that type of engine is that is has to run without oil-lubrication. Piston rings made of Rylon are used to solve this problem. A special feature of the engine that has been constructed here is that the inner surface of the glass may be cleaned without removing the cylinder head. This is obtained by a construction with a movable cylinder. In cleaning-state the cylinder is driven up and down together with the piston, while the head is supported by an outer structure. When running the engine, the cylinder is fixed to the structure. Furthermore this report contains the necessary calculations and integrity assessments on the critical parts of the construction. All calculations, except the

  6. A Technical Review of Compressed Natural Gas as an Alternative Fuel for Internal Combustion Engines

    Directory of Open Access Journals (Sweden)

    Semin

    2008-01-01

    Full Text Available Natural gas is promising alternative fuel to meet strict engine emission regulations in many countries. Compressed natural gas (CNG has long been used in stationary engines, but the application of CNG as a transport engines fuel has been considerably advanced over the last decade by the development of lightweight high-pressure storage cylinders. Engine conversion technology is well established and suitable conversion equipment is readily available. For spark ignition engines there are two options, a bi-fuel conversion and use a dedicated to CNG engine. For compression ignition engines converted to run on natural gas, there are two main options discussed, there are dual-fuel engines and normal ignition can be initiated. Natural gas engines can operate at lean burn and stoichiometric conditions with different combustion and emission characteristics. In this paper, the CNG engines research and development fueled using CNG are highlighted to keep the output power, torque and emissions of natural gas engines comparable to their gasoline or diesel counterparts. The high activities for future CNG engines research and development to meet future CNG engines is recorded in the paper.

  7. ABC - alcohol based combustion engines. Challenges and opportunities

    Energy Technology Data Exchange (ETDEWEB)

    Bergstroem, K.; Nordin, H.; Koenigstein, A. [GM Powertrain Europe (Austria); Marriott, C.D.; Wiles, M.A. [GM Powertrain North America (United States)

    2007-07-01

    Ethanol as a fuel for individual transportation represents one answer to the future challenges regarding energy availability, energy accessibility and environmental compatibility. In the first generation of flex-fuel engines (an engine capable of operating with different ethanol blends) the challenge was to modify existing hardware in order to make the engines durable in a more aggressive environment (corrosion, wear) of ethanol, and to have controls available to run w/ different ethanol blends. Besides the significant improvement in CO{sub 2}-emissions, especially if considered on a well-to-wheels basis, quite significant improvements in regard to full-load performance were achieved. With the next generation of flex-fuel engines, based on state-of-the-art SIDI turbo technology, full-load efficiency (i.e. fuel consumption) can be further improved, since these engines are already designed for higher in-cylinder peak pressures. Full potential will be gained if there will be a dedicated design for flex-fuel engines, enabling peak pressures of about 120 bar. With this capability the full-load fuel consumption can be reduced by an additional 10%, without being penalized by fuel enrichment demands for component protection purposes. As an alternative, maximum peak pressure and full-load fuel consumption can be kept constant while increasing the compression ratio to CR=11-12 in order to address part-load fuel consumption. Such a compression ratio has never been seen before on a turbo charged engine. Before this becomes a standard technology further efforts have to be spent in order to provide sufficient infrastructure/fuelling stations on a European basis. Sweden represents a good example of how this technology can be implemented - but Sweden alone is not sufficient to make this a success story. Promotion by the European government and the regional governments is required as well. (orig.)

  8. Chemical-Looping Combustion and Gasification of Coals and Oxygen Carrier Development: A Brief Review

    Directory of Open Access Journals (Sweden)

    Ping Wang

    2015-09-01

    Full Text Available Chemical-looping technology is one of the promising CO2 capture technologies. It generates a CO2 enriched flue gas, which will greatly benefit CO2 capture, utilization or sequestration. Both chemical-looping combustion (CLC and chemical-looping gasification (CLG have the potential to be used to generate power, chemicals, and liquid fuels. Chemical-looping is an oxygen transporting process using oxygen carriers. Recently, attention has focused on solid fuels such as coal. Coal chemical-looping reactions are more complicated than gaseous fuels due to coal properties (like mineral matter and the complex reaction pathways involving solid fuels. The mineral matter/ash and sulfur in coal may affect the activity of oxygen carriers. Oxygen carriers are the key issue in chemical-looping processes. Thermogravimetric analysis (TGA has been widely used for the development of oxygen carriers (e.g., oxide reactivity. Two proposed processes for the CLC of solid fuels are in-situ Gasification Chemical-Looping Combustion (iG-CLC and Chemical-Looping with Oxygen Uncoupling (CLOU. The objectives of this review are to discuss various chemical-looping processes with coal, summarize TGA applications in oxygen carrier development, and outline the major challenges associated with coal chemical-looping in iG-CLC and CLOU.

  9. Chemical Engineering Division research highlights, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Burris, L.; Webster, D. S.; Barney, D. L.; Cafasso, F. A.; Steindler, M. J.

    1980-06-01

    In 1979, CEN conducted research and development in the following areas: (1) high-temperature, rechargeable lithium/iron sulfide batteries for electric vehicles and electric utility load leveling; (2) ambient-temperature batteries - improved lead-acid, nickel/zinc, and nickel/iron - for electric vehicles; (3) molten carbonate fuel cells for use by electric utilities; (4) coal technology - mainly fluidized-bed combustion of coal in the presence of SO/sub 2/ sorbent of limestone; (5) heat- and seed- recovery technology for open-cycle magnetohydrodynamic systems; (6) solar energy collectors and thermal energy storage; (7) fast breeder reactor chemistry research - chemical support of reactor safety studies, chemistry of irradiated fuels, and sodium technology; (8) fuel cycle technology - reprocessing of nuclear fuels, management of nuclear wastes, geologic migration studies, and proof-of-breeding studies for the Light Water Breeder Reactor; (9) magnetic fusion research - lithium processing technology and materials research; and (10) basic energy sciences - homogeneous catalysis, thermodynamics of inorganic and organic materials, environmental chemistry, electrochemistry, and physical properties of salt vapors. Separate abstracts were prepared for each of these areas.

  10. Combustion characteristics of a direct-injection diesel engine fueled with Fischer-Tropsch diesel

    Institute of Scientific and Technical Information of China (English)

    HUANG Yongcheng; ZHOU Longbao; PAN Keyu

    2007-01-01

    Fischer-Tropsch (F-T) diesel fuel is characterized by a high cetane number, a near-zero sulphur content and a very low aromatic level. On the basis of the recorded incylinder pressures and injector needle lifts, the combustion characteristics of an unmodified single-cylinder directinjection diesel engine operating on F-T diesel fuel are analyzed and compared with those of conventional diesel fuel operation. The results show that F-T diesel fuel exhibits a slightly longer injection delay and injection duration, an average of 18.7% shorter ignition delay, and a comparable total combustion duration when compared to those of conventional diesel fuel. Meanwhile, F-T diesel fuel displays an average of 26.8% lower peak value of premixed burning rate and a higher peak value of diffusive burning rate. In addition, the F-T diesel engine has a slightly lower peak combustion pressure, a far lower rate of pressure rise, and a lower mechanical load and combustion noise than the conventional diesel engine. The brake specific fuel consumption is lower and the effective thermal efficiency is higher for F-T diesel fuel operation.

  11. Effects of Fischer-Tropsch diesel fuel on combustion and emissions of direct injection diesel engine

    Institute of Scientific and Technical Information of China (English)

    Yongcheng HUANG; Shangxue WANG; Longbao ZHOU

    2008-01-01

    Effects of Fischer-Tropsch (F-T) diesel fuel on the combustion and emission characteristics of a single-cylinder direct injection diesel engine under different fuel delivery advance angles were investigated. The experi-mental results show that F-T diesel fuel exhibits shorter ignition delay, lower peak values of premixed burning rate, lower combustion pressure and pressure rise rate, and higher peak value of diffusion burning rate than con-ventional diesel fuel when the engine remains unmodified. In addition, the unmodified engine with F-T diesel fuel has lower brake specific fuel consumption and higher effective thermal efficiency, and presents lower HC, CO, NOx and smoke emissions than conventional diesel fuel. When fuel delivery advance angle is retarded by 3 crank angle degrees, the combustion duration is obviously shor-tened; the peak values of premixed burning rate, the com-bustion pressure and pressure rise rate are further reduced; and the peak value of diffusion burning rate is further increased for F-T diesel fuel operation, Moreover, the retardation of fuel delivery advance angle results in a further significant reduction in NOx emissions with no penalty on specific fuel consumption and with much less penalty on HC, CO and smoke emissions.

  12. Performance Evaluation of an Ultra-Lean Combustion Studies in IC Engines

    Directory of Open Access Journals (Sweden)

    Puli Ravi Kumar

    2016-01-01

    Full Text Available An investigation was made to determine the effects of ethanol at ultra-lean effective systems utilizing an experimental study. The present study is planned to develop and evaluate the performance, emission and combustion characteristics of the ultra-lean burn Internal Combustion engine was modified to operate on ethanol blends fuels. The study looked at part throttle, constant speed operation of 0%, 10%, and 15% ethanol blends with gasoline mixtures operating in ultra-lean operating systems. In experiment practice the use of homogeneous lean mixtures in engine has been handicapped by several difficulties. The most serious one is that the flame propagation through mixtures becomes gradually slower as the mixture becomes leaner. The mixture distribution in a multi-cylinder engine is a problem because even small variation in mixture ratio on the linear side will strongly effect power output. Enhancement of lean combustion of homogeneous mixtures can be achieved by (i using ethanol blends with gasoline (ii using high-ignition energy (iii providing high compression ratios (iv creating high swirl in the combustion chamber.

  13. Combustion, Performance and Emission Analysis of an Oxygen-Controlling Downsized SI Engine

    Directory of Open Access Journals (Sweden)

    Zhou J.X.

    2016-07-01

    Full Text Available In the present study, experiments were carried out in a single-cylinder downsized SI engine with different rates of oxygen (15% to 27% by volume in the total mixture of intake gases except fuel and equivalence ratios (from 0.45 to 1. Therefore, the oxygen volume fraction is due to oxygen enrichment or nitrogen dilution. The study of the impact of controlling the oxygen concentration on the combustion characteristics and emissions was performed at 1 400 rpm, at several loads (Indicated Mean Effective Pressure (IMEP from 400 to 1 000 kPa. For each operation point, the spark advance and the intake pressure were adjusted simultaneously in order to maintain the load and obtain a minimum value of the indicated Specific Fuel Consumption (SFC. The effect of the oxygen concentration on the engine combustion characteristics was simulated by using the commercial software AMESim, with the combustion model developed by IFP Energies nouvelles, and an adapted algorithm was used to avoid residual gas calibration. By implementing a correlation for the laminar burning velocity, the in-cylinder pressures were perfectly predicted with a maximum pressure relative error of less than 2% for almost all the operating points. The classification of engine combustion according to the Peters-Borghi diagram, gives a deeper insight into the interaction between turbulence and the flame front.

  14. A novel reactor configuration for packed bed chemical-looping combustion of syngas

    NARCIS (Netherlands)

    Hamers, H.P.; Gallucci, F.; Cobden, P.D.; Kimball, E.; Sint Annaland, M. van

    2013-01-01

    This study reports on the application of chemical looping combustion (CLC) in pressurized packed bed reactors using syngas as a fuel. High pressure operation of CLC in packed bed has a different set of challenges in terms of material properties, cycle and reactor design compared to fluidized bed ope

  15. Large eddy simulation of combustion characteristics in a kerosene fueled rocket-based combined-cycle engine combustor

    Science.gov (United States)

    Huang, Zhi-wei; He, Guo-qiang; Qin, Fei; Cao, Dong-gang; Wei, Xiang-geng; Shi, Lei

    2016-10-01

    This study reports combustion characteristics of a rocket-based combined-cycle engine combustor operating at ramjet mode numerically. Compressible large eddy simulation with liquid kerosene sprayed and vaporized is used to study the intrinsic unsteadiness of combustion in such a propulsion system. Results for the pressure oscillation amplitude and frequency in the combustor as well as the wall pressure distribution along the flow-path, are validated using experimental data, and they show acceptable agreement. Coupled with reduced chemical kinetics of kerosene, results are compared with the simultaneously obtained Reynolds-Averaged Navier-Stokes results, and show significant differences. A flow field analysis is also carried out for further study of the turbulent flame structures. Mixture fraction is used to determine the most probable flame location in the combustor at stoichiometric condition. Spatial distributions of the Takeno flame index, scalar dissipation rate, and heat release rate reveal that different combustion modes, such as premixed and non-premixed modes, coexisted at different sections of the combustor. The RBCC combustor is divided into different regions characterized by their non-uniform features. Flame stabilization mechanism, i.e., flame propagation or fuel auto-ignition, and their relative importance, is also determined at different regions in the combustor.

  16. Combustion chemistry and formation of pollutants; Chimie de la combustion et formation des polluants

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    This book of proceedings reports on 7 papers on combustion chemistry and formation of pollutants presented during the workshop organized by the `Combustion and Flames` section of the French society of thermal engineers. The chemistry of combustion is analyzed in various situations such as: turbojet engines, spark ignition engines, industrial burners, gas turbines etc... Numerical simulation is used to understand the physico-chemical processes involved in combustion, to describe the kinetics of oxidation, combustion and flame propagation, and to predict the formation of pollutants. (J.S.)

  17. Theoretical Combustion Performance of Several High-Energy Fuels for Ramjet Engines

    Science.gov (United States)

    Tower, Leonard K; Breitwieser, Roland; Gammon, Benson E

    1958-01-01

    An analytical evaluation of the air and fuel specific-impulse characteristics of magnesium, magnesium octene-1 slurries, aluminum, aluminum octene-1 slurries, boron, boron octene-1 slurries, carbon, hydrogen, alpha-methylnaphthalene, diborane, pentaborane, and octene-1 is presented. While chemical equilibrium was assumed in the combustion process, the expansion was assumed to occur at fixed composition.

  18. Research on Measurements for Temperature and Stress of Pistons in Internal Combustion Engine

    Institute of Scientific and Technical Information of China (English)

    DONG Xiao-rui; TAN Jian-song

    2008-01-01

    In both numerical simulation and experimental research for the piston of internal combustion engine, the verification foundations are always insufficient. The reason is the measurements for its transient temperature and stress under actual operation conditions are very difficult. A multi-channel measurement-storage technology is used in the engine bench experiment to measure the piston temperature and stress in real time. The temperature and stress changes in the engine operation process are obtained. They provide reliable instructive criteria for numerical analysis and experiment of the piston working state.

  19. A transient tribodynamic approach for the calculation of internal combustion engine piston slap noise

    Science.gov (United States)

    Dolatabadi, N.; Littlefair, B.; De la Cruz, M.; Theodossiades, S.; Rothberg, S. J.; Rahnejat, H.

    2015-09-01

    An analytical/numerical methodology is presented to calculate the radiated noise due to internal combustion engine piston impacts on the cylinder liner through a film of lubricant. Both quasi-static and transient dynamic analyses coupled with impact elasto-hydrodynamics are reported. The local impact impedance is calculated, as well as the transferred energy onto the cylinder liner. The simulations are verified against experimental results for different engine operating conditions and for noise levels calculated in the vicinity of the engine block. Continuous wavelet signal processing is performed to identify the occurrence of piston slap noise events and their spectral content, showing good conformance between the predictions and experimentally acquired signals.

  20. HEAT RECOVERY FROM A NATURAL GAS POWERED INTERNAL COMBUSTION ENGINE BY CO2 TRANSCRITICAL POWER CYCLE

    Directory of Open Access Journals (Sweden)

    Mahmood Farzaneh-Gord

    2010-01-01

    Full Text Available The present work provides details of energy accounting of a natural gas powered internal combustion engine and achievable work of a utilized CO2 power cycle. Based on experimental performance analysis of a new designed IKCO (Iran Khodro Company 1.7 litre natural gas powered engine, full energy accounting of the engine were carried out on various engine speeds and loads. Further, various CO2 transcritical power cycle configurations have been appointed to take advantages of exhaust and coolant water heat lost. Based on thermodynamic analysis, the amount of recoverable work obtainable by CO2 transcritical power cycles have been calculated on various engine conditions. The results show that as much as 18 kW power could be generated by the power cycle. This would be considerable amount of power especially if compared with the engine brake power.

  1. North Kyushu meeting of Chemical Engineering Association

    Energy Technology Data Exchange (ETDEWEB)

    1981-01-01

    Proceedings are presented of a conference held in Japan that was concerned with many aspects of coal related technology. Topics covered include spontaneous combustion, problems of coal storage and handling, pulverized coal, coal pelletization and briquetting, coal gasification, coal liquefaction and fluidized-bed combustion. Thirteen papers are abstracted separately.

  2. EXTENDING THE KNOWLEDGE BASE OF CHEMICAL ENGINEERING

    Institute of Scientific and Technical Information of China (English)

    Mooson Kwauk

    2005-01-01

    The obvious current reversion to micro-scale investigations in basic chemical engineering, combined with the need, of a quite different nature, in the rapid growth of high added-value and small-lot functional materials, have been pointing to an area not yet sufficiently covered by the unit operations, transport phenomena and chemical reaction engineering. Although it is difficult to define accurately this area, a cursory scan of the activities already in progress has revealed a few common attributes: multi-phased (structured), multi-scaled, multi-disciplined, nonlinear, needs for resolution to reductionism-solvable subsystems, and pervasive in the process industry. From these activities, the present paper drafts a tentative scheme for studying the related problems: first to dissect a problem into various scales - spatial, temporal or otherwise as best suits the case in hand- in order to identify pertinent parameters which are then organized into model formulations. Together with inter-scale model formulations, a zoom-in/zoom-out process is carried out between the scales, by trial-and-error and through reasoning, to arrive at a global formulation of a quantitative solution, in order to derive, eventually, the general from the particular.

  3. The research and development of in situ non intrusive optical and temperature diagnostics in an internal combustion engine

    CERN Document Server

    Wilson, T S

    2002-01-01

    Novel instrumentation has been developed and evaluated in a low-cost, purpose built, single-cylinder internal combustion engine test facility designed to simulate many of the combustion features that are common between an internal combustion engine, a gas turbine combustor and a steel rolling furnace. High bandwidth in-cylinder surface temperature measurements are demonstrated with a new application of platinum thin film resistance thermometers. These gauges are exposed to the combustion gases and are mounted to both the cylinder head and piston. It is shown that calculation of flame speed, determination of heat flux levels and flame structure observation are possible. Fibre optic probes capable of high frequency spectral measurements of the combustion emission are presented. The spectral measurements are shown to complement the temperature measurement by being able to differentiate the flame front from the general combustion emission and hot by-products. Beyond this, other optical techniques have been explor...

  4. Three-dimensional modeling of diesel engine intake flow, combustion and emissions-2

    Science.gov (United States)

    Reitz, R. D.; Rutland, C. J.

    1993-01-01

    A three-dimensional computer code, KIVA, is being modified to include state-of-the-art submodels for diesel engine flow and combustion. Improved and/or new submodels which have already been implemented and previously reported are: wall heat transfer with unsteadiness and compressibility, laminar-turbulent characteristic time combustion with unburned HC and Zeldo'vich NO(x), and spray/wall impingement with rebounding and sliding drops. Progress on the implementation of improved spray drop drag and drop breakup models, the formulation and testing of a multistep kinetics ignition model, and preliminary soot modeling results are described. In addition, the use of a block structured version of KIVA to model the intake flow process is described. A grid generation scheme was developed for modeling realistic (complex) engine geometries, and computations were made of intake flow in the ports and combustion chamber of a two-intake-value engine. The research also involves the use of the code to assess the effects of subprocesses on diesel engine performance. The accuracy of the predictions is being tested by comparisons with engine experiments. To date, comparisons were made with measured engine cylinder pressure, temperature and heat flux data, and the model results are in good agreement with the experiments. Work is in progress that will allow validation of in-cylinder flow and soot formation predictions. An engine test facility is described that is being used to provide the needed validation data. Test results were obtained showing the effect of injection rate and split injections on engine performance and emissions.

  5. Combustion Model and Control Parameter Optimization Methods for Single Cylinder Diesel Engine

    Directory of Open Access Journals (Sweden)

    Bambang Wahono

    2014-01-01

    Full Text Available This research presents a method to construct a combustion model and a method to optimize some control parameters of diesel engine in order to develop a model-based control system. The construction purpose of the model is to appropriately manage some control parameters to obtain the values of fuel consumption and emission as the engine output objectives. Stepwise method considering multicollinearity was applied to construct combustion model with the polynomial model. Using the experimental data of a single cylinder diesel engine, the model of power, BSFC, NOx, and soot on multiple injection diesel engines was built. The proposed method succesfully developed the model that describes control parameters in relation to the engine outputs. Although many control devices can be mounted to diesel engine, optimization technique is required to utilize this method in finding optimal engine operating conditions efficiently beside the existing development of individual emission control methods. Particle swarm optimization (PSO was used to calculate control parameters to optimize fuel consumption and emission based on the model. The proposed method is able to calculate control parameters efficiently to optimize evaluation item based on the model. Finally, the model which added PSO then was compiled in a microcontroller.

  6. Brayton cycle for internal combustion engine exhaust gas waste heat recovery

    Directory of Open Access Journals (Sweden)

    J Galindo

    2015-06-01

    Full Text Available An average passenger car engine effectively uses about one-third of the fuel combustion energy, while the two-thirds are wasted through exhaust gases and engine cooling. It is of great interest to automotive industry to recover some of this wasted energy, thus increasing the engine efficiency and lowering fuel consumption and contamination. Waste heat recovery for internal combustion engine exhaust gases using Brayton cycle machine was investigated. The principle problems of application of such a system in a passenger car were considered: compressor and expander machine selection, machine size for packaging under the hood, efficiency of the cycle, and improvement of engine efficiency. Important parameters of machines design have been determined and analyzed. An average 2-L turbocharged gasoline engine’s New European Driving Cycle points were taken as inlet points for waste heat recovery system. It is theoretically estimated that the recuperated power of 1515 W can be achieved along with 5.7% improvement in engine efficiency, at the point where engine power is 26550 W.

  7. Combustion characteristics of spark-ignition and pilot flame ignition systems in a model Wankel stratified charge engine

    Energy Technology Data Exchange (ETDEWEB)

    Muroki, T. [Kanagawa Inst. of Technology, Dept. of Mechanical Engineering, Kanagawa (Japan); Moriyoshi, Y. [Chiba Univ., Dept. of Electronics and Mechanical Engineering, Chiba (Japan)

    2000-11-01

    In a stratified charge engine, a glow plug pilot flame ignition system has been compared with a spark-ignition system for a model stratified charge Wankel combustion chamber. A motored two-stroke diesel engine was operated as a rapid compression and expansion machine with the cylinder head replaced by a model Wankel combustion chamber designed to simulate the temporal changes of air flow and pressure fields inside the chamber of an actual engine. It was found that the pilot flame ignition system had better ignitability and improved combustion characteristics, especially in the lean mixture range, relative to the spark-ignition system. (Author)

  8. Optimizing Spray and Combustion in Diesel Engine by Multidimensional Numerical Simulation

    Institute of Scientific and Technical Information of China (English)

    ZHOU Lei; ZHAO Chang-lu; ZHANG Fu-jun

    2005-01-01

    The calculation of spray and combustion in diesel engines is described by using the softwares FIRE and BOOST. The application of the resulting computational method to the simulation of fuel spray and breakup, mixture formation and combustion in a heavy duty diesel is presented. According to detailed insight into the governing processes provided by the simulation results, various aspects of the dependence of the spray propagation and combustion on the chamber geometry and spray angle are discussed. Then, global cylinderaveraged pressure traces are extracted from the space and time resolved field quantities and compared to incylinder pressure measurements. Finally, an optimized configuration of the chamber geometry and spray angle with a new injection rate of higher injection pressure is proposed.

  9. A Preliminary Motion-picture Study of Combustion in a Compression-ignition Engine

    Science.gov (United States)

    Buckley, E C; Waldron, C D

    1934-01-01

    Motion pictures were taken at 1,850 frames per second of the spray penetration and combustion occurring in the N.A.C.A. combustion apparatus arranged to operate as a compression-ignition engine. Indicator cards were taken simultaneously with the motion pictures by means of the N.A.C.A. optical indicator. The motion pictures showed that when ignition occurred during injection it started in the spray envelope. If ignition occurred after injection cut-off, however, and after considerable mixing had taken place, it was impossible to predict where the ignition would start. The pictures also showed that ignition usually started at several points in the combustion chamber. With this apparatus, as the injection advance angle increased from 0 degrees to 40 degrees before top center, the rate of flame spread increased and the duration of the burning decreased.

  10. Membrane Systems Engineering for Post-combustion Carbon Capture

    KAUST Repository

    Alshehri, Ali

    2013-08-05

    This study proposes a strategy for optimal design of hollow fiber membrane networks for post combustion carbon capture from power plant multicomponent flue gas. A mathematical model describing multicomponent gas permeation through a separation membrane was customized into the flowsheet modeling package ASPEN PLUS. An N-stage membrane network superstructure was defined considering all possible flowsheeting configurations. An optimization formulation was then developed and solved using an objective function that minimizes the costs associated with operating and capital expenses. For a case study of flue gas feed flow rate of 298 m3/s with 13% CO2 and under defined economic parameters, the optimization resulted in the synthesis of a membrane network structure consisting of two stages in series. This optimal design was found while also considering feed and permeate pressures as well as recycle ratios between stages. The cost of carbon capture for this optimal membrane network is estimated to be $28 per tonne of CO2 captured, considering a membrane permeance of 1000 GPU and membrane selectivity of 50. Following this approach, a reduction in capture cost to less than $20 per tonne CO2 captured is possible if membranes with permeance of 2000 GPU and selectivity higher than 70 materialize.

  11. Soot filter for the exhaust gas of internal combustion engines

    Energy Technology Data Exchange (ETDEWEB)

    Abthoff, J.; Schuster, H.D.; Langer, H.J.

    1980-06-19

    In the previously known soot filters, the exhaust gas flows through the cylindrical filter radially from the outside to the inside. The exhaust gas touches a relatively large area of the filter housing and therefore loses a large part of the thermal energy required for post-combustion. According to the invention, these disadvantages are avoided in the new filter, where the filter material forms hollow spaces at the internal wall of the filter, which take the exhaust gas after it has flowed through the filter and carry it in an axial direction of the filter housing to the exhaust. Due to this design of the filter and the saving in heat, the areas on which the exhaust gas impinges can be kept appreciably smaller and better use can be made of the heat in the exhaust gas. The ceramic filter material can consist of an outer layer of loose ceramic fibres and an inner woven ceramic fibre mat. In order to increase the effectiveness of the filter, the soot filter can be used as a fine filter after a coarse filter.

  12. Biomass Power Generation through Direct Integration of Updraft Gasifier and Stirling Engine Combustion System

    Directory of Open Access Journals (Sweden)

    Jai-Houng Leu

    2010-01-01

    Full Text Available Biomass is the largest renewable energy source in the world. Its importance grows gradually in the future energy market. Since most biomass sources are low in energy density and are widespread in space, small-scale biomass conversion system is therefore more competitive than a large stand-alone conversion plant. The current study proposes a small-scale solid biomass power system to explore the viability of direct coupling of an updraft fixed bed gasifier with a Stirling engine. The modified updraft fixed bed gasifier employs an embedded combustor inside the gasifier to fully combust the synthetic gas generated by the gasifier. The flue gas produced by the synthetic gas combustion inside the combustion tube is piped directly to the heater head of the Stirling engine. The engine will then extract and convert the heat contained in the flue gas into electricity automatically. Output depends on heat input. And, the heat input is proportional to the flow rate and temperature of the flue gas. The preliminary study of the proposed direct coupling of an updraft gasifier with a 25 kW Stirling engine demonstrates that full power output could be produced by the current system. It could be found from the current investigation that no auxiliary fuel is required to operate the current system smoothly. The proposed technology and units could be considered as a viable solid biomass power system.

  13. Exergetic analysis of cogeneration plants through integration of internal combustion engine and process simulators

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Leonardo de Oliveira [Petroleo Brasileiro S.A. (PETROBRAS), Rio de Janeiro, RJ (Brazil)], E-mail: leonardo.carvalho@petrobras.com.br; Leiroz, Albino Kalab; Cruz, Manuel Ernani [Coordenacao dos Programas de Pos-Graduacao de Engenharia (COPPE/UFRJ), RJ (Brazil). Programa de Engenharia Mecanica], Emails: leiroz@mecanica.ufrj.br, manuel@mecanica.ufrj.br

    2010-07-01

    Internal combustion engines (ICEs) have been used in industry and power generation much before they were massively employed for transportation. Their high reliability, excellent power-to-weight ratio, and thermal efficiency have made them a competitive choice as main energy converters in small to medium sized power plants. Process simulators can model ICE powered energy plants with limited depth, due to the highly simplified ICE models used. Usually a better understanding of the global effects of different engine parameters is desirable, since the combustion process within the ICE is typically the main cause of exergy destruction in systems which utilize them. Dedicated commercial ICE simulators have reached such a degree of maturity, that they can adequately model a wide spectrum of phenomena that occur in ICEs. However, ICE simulators are unable to incorporate the remaining of power plant equipment and processes in their models. This paper presents and exploits the integration of an internal combustion engine simulator with a process simulator, so as to evaluate the construction of a fully coupled simulation platform to analyze the performance of ICE-based power plants. A simulation model of an actual cogeneration plant is used as a vehicle for application of the proposed computational methodology. The results show that by manipulating the engine mapping parameters, the overall efficiency of the plant can be improved. (author)

  14. Design Analysis and Optimization of Internal Combustion Engine Piston using CAE tool ANSYS

    Directory of Open Access Journals (Sweden)

    Aditya Kumar Gupta

    2014-11-01

    Full Text Available In the internal combustion engine there are many reciprocating parts which are responsible for giving the motion to the engine. from them the piston is very important part of the internal combustion engine.. The working condition of the piston is so worst in comparison of other parts of the internal combustion engine. There is very high probability to failure of the piston due to high wear and tear. So there is necessary to inspection the working condition of piston. In before there is no availability of software packages. So there is difficult to check out the failure of the piston, it is also very time taken process. In now days the software packages are used to consume less time and give quality assurance. In this study work there are two steps of analysis of the piston they are Designing and Analysis. Firstly design the model of the piston in giving design specification on the modelling software like INVENTOR . Then giving it the constraints which are act on the working condition of the piston after import the model of the piston into the analysis software ANSYS in IGES format. Then the analysis become completed on the different parameters(temperature, stress, deformation and easily analysis the result. In this work the piston become optimized after the reducing the material of the piston. the mass and volume of the piston become reduced. The deformation also increased after the optimization which is responsible for the stress distribution on the piston head or piston crown.

  15. Future combustion methods for biomethane powered tractor engines; Zukuenftige Brennverfahren fuer biomethanbetriebene Traktormotoren

    Energy Technology Data Exchange (ETDEWEB)

    Prehn, Sascha; Harndorf, Horst [Rostock Univ. (Germany). Lehrstuhl fuer Kolbenmaschinen und Verbrennungsmotoren; Wichmann, Volker [Rostock Univ. (Germany). Maschinenlabor; Beberdick, Wolfgang

    2016-08-01

    Biomethane represents an alternative to fossil fuels (petrol, diesel), not only in the on-road sector. Methane-based fuels come in focus of farmers in the agriculture sector, due to cost constraints, increasing regulation of pollutant emissions and reduction of carbondioxid. To represent a monovalent gas operation, a functional model is derived from a series diesel engine for agricultural use. On the test engine, systematic studies on the combustion process are carried out by cylinder pressure indication and exhaust-emission measurement. Combustion under stoichiometric conditions (with or without exhaust gas recirculation) as well as the conversion of fuel from excess air is observed. The study shows that with a natural-gas engine, a complex post-treatment system of exhaust gas (DOC + DPF + SCR) that is typically for diesel engines can be dispensed with. The exhaust gas limits in force since 2014 and a limitation of methane on 0,5 g/kWh can be met with a stoichiometric combustion concept and a three way catalytic converter optimized for the methane oxidation.

  16. Chemical looping combustion: A new low-dioxin energy conversion technology.

    Science.gov (United States)

    Hua, Xiuning; Wang, Wei

    2015-06-01

    Dioxin production is a worldwide concern because of its persistence and carcinogenic, teratogenic, and mutagenic effects. The pyrolysis-chemical looping combustion process of disposing solid waste is an alternative to traditional solid waste incineration developed to reduce the dioxin production. Based on the equilibrium composition of the Deacon reaction, pyrolysis gas oxidized by seven common oxygen carriers, namely, CuO, NiO, CaSO4, CoO, Fe2O3, Mn3O4, and FeTiO3, is studied and compared with the pyrolysis gas directly combusted by air. The result shows that the activity of the Deacon reaction for oxygen carriers is lower than that for air. For four typical oxygen carriers (CuO, NiO, Fe2O3, and FeTiO3), the influences of temperature, pressure, gas composition, and tar on the Deacon reaction are discussed in detail. According to these simulation results, the dioxin production in China, Europe, the United States, and Japan is predicted for solid waste disposal by the pyrolysis-chemical looping combustion process. Thermodynamic analysis results in this paper show that chemical looping combustion can reduce dioxin production in the disposal of solid waste.

  17. Creating mechanisms of toxic substances emission of combustion engines

    Directory of Open Access Journals (Sweden)

    Jankowski Antoni

    2015-12-01

    Full Text Available The paper analyses the mechanisms of creation of toxic exhaust gases, which mainly derived from inexact fuel metering and improper air-fuel mixture preparation. The paper describes the process of creating toxic components in the exhaust gases of piston engines during engine operation, and impact on the emission of these components determining the composition of the fuel mixture determined equivalence factor Φ. The principal mechanisms of formation of toxic exhaust gases, in particular nitrogen oxides, carbon monoxide and hydrocarbons, and also essential according to create each of toxic exhaust gases are the subject of the paper. Moreover, empirical relationships, by means of which it is possible to determine the time of creation of the individual components of toxic exhaust gases, are presented. For example, one of the mechanisms for prompt formation of nitrogen oxides and hydrocarbons graphic illustration of formation as a function of crank angle is described. At the conclusion, the summary and significance of information on creation mechanisms of toxic components in the exhaust gases of piston engines are presented.

  18. ENGINEERED BARRIER SYSTEM: PHYSICAL AND CHEMICAL ENVIRONMENT

    Energy Technology Data Exchange (ETDEWEB)

    R. Jarek

    2005-08-29

    The purpose of this model report is to describe the evolution of the physical and chemical environmental conditions within the waste emplacement drifts of the repository, including the drip shield and waste package surfaces. The resulting seepage evaporation and gas abstraction models are used in the total system performance assessment for the license application (TSPA-LA) to assess the performance of the engineered barrier system and the waste form. This report develops and documents a set of abstraction-level models that describe the engineered barrier system physical and chemical environment. Where possible, these models use information directly from other reports as input, which promotes integration among process models used for TSPA-LA. Specific tasks and activities of modeling the physical and chemical environment are included in ''Technical Work Plan for: Near-Field Environment and Transport In-Drift Geochemistry Model Report Integration'' (BSC 2005 [DIRS 173782], Section 1.2.2). As described in the technical work plan, the development of this report is coordinated with the development of other engineered barrier system reports. To be consistent with other project documents that address features, events, and processes (FEPs), Table 6.14.1 of the current report includes updates to FEP numbers and FEP subjects for two FEPs identified in the technical work plan (TWP) governing this report (BSC 2005 [DIRS 173782]). FEP 2.1.09.06.0A (Reduction-oxidation potential in EBS), as listed in Table 2 of the TWP (BSC 2005 [DIRS 173782]), has been updated in the current report to FEP 2.1.09.06.0B (Reduction-oxidation potential in Drifts; see Table 6.14-1). FEP 2.1.09.07.0A (Reaction kinetics in EBS), as listed in Table 2 of the TWP (BSC 2005 [DIRS 173782]), has been updated in the current report to FEP 2.1.09.07.0B (Reaction kinetics in Drifts; see Table 6.14-1). These deviations from the TWP are justified because they improve integration with FEPs

  19. Combustion of the alternative marine diesel fuel LCO in large diesel engines; Verbrennung des alternativen Marinekraftstoffs LCO in Grossdieselmotoren

    Energy Technology Data Exchange (ETDEWEB)

    Struckmeier, Daniel; Takasaki, Koji; Tajima, Hiroshi [Kyushu Univ., Fukuoka (JP). Lab. of Engine and Combustion (ECO)

    2008-11-15

    Large diesel engines represent the heart of the ships, which transport worldwide about 80% of the goods over the sea route these days. Regimentations of the IMO are planning drastic reductions of nitrogen oxide and sulfur oxide emission limitations from marine diesel engines. At the Laboratory of Engine and Combustion (ECO) of the Kyushu University in Fukuoka (Japan), experiments were carried out on a medium size, single cylinder, diesel engine with two-stroke technology in order to investigate the use of Light Cycle Oil (LCO) in large diesel engines with new combustion processes. (orig.)

  20. Combustion Characteristics of a Diesel Engine Using Propanol Diesel Fuel Blends

    Science.gov (United States)

    Muthaiyan, Pugazhvadivu; Gomathinayagam, Sankaranarayanan

    2016-07-01

    The objective of the work is to study the use of propanol diesel blends as alternative fuel in a single cylinder diesel engine. In this work, four different propanol diesel blends containing 10, 15, 20 and 25 % propanol in diesel by volume were used as fuels. Load tests were conducted on the diesel engine and the combustion parameters such as cylinder gas pressure, ignition delay, rate of heat release and rate of pressure rise were investigated. The engine performance and emission characteristics were also studied. The propanol diesel blends showed longer ignition delay, higher rates of heat release and pressure rise. The thermal efficiency of the engine decreased marginally with the use of fuel blends. The propanol diesel blends decreased the CO, NOX and smoke emissions of the engine considerably.

  1. COMBUSTION CHARACTERISTICS OF CI ENGINE USING KARANJA BIODIESEL BLENDS AS FUEL

    Directory of Open Access Journals (Sweden)

    H.A. PHADTARE

    2013-05-01

    Full Text Available Karanja based bio-diesel is a non-edible, biodegradable fuel suitable for diesel engines. Karanja biodiesel has been prepared by transesterification method. Biodiesel-diesel blends have been prepared on volume basis. Physical properties of Karanja biodiesel, diesel and its blends have been determined. An experimentalinvestigation has been carried out to analyze combustion characteristics of a single cylinder, VCR diesel engine fuelled with Karanja biodiesel and its blends (10%, 20%, 30%, 50% and 75% with neat diesel. A series of engine tests, with CR 16.5, 17.5 and 18.5 have been conducted using each of the above blends for comparativeevaluation. Combustion parameters such as ignition delay, peak pressure development, heat release rate analysis of engine have been studied. The results of the experiment in each case have been compared with baseline data of neat diesel. Ignition delays of bio-diesel blends are lower than that of diesel; peak pressure takes place definitely after TDC for safe and efficient operation. Comparable rate of pressure rise obtained is indicative of stable and noise free operation of CI engines with karanja biodiesel blends. B10 is suitable alternative fuel for diesel at slightly higher CR can be used without any engine modifications.

  2. UV laser spectroscopic measurements in jet engine combustion exit flows

    Energy Technology Data Exchange (ETDEWEB)

    Shirley, J.A. (United Technologies Research Center, East Hartford, CT (United States))

    1992-01-01

    Laser diagnostic measurements, which are excited with a narrowband krypton fluoride laser, have been made at the exit of a jet engine combustor. Spectra of Raman scattering and laser induced fluorescence were measured with a 0.5 meter spectrograph equipped with a diode array detector. For these demonstration tests, the combustor was operated at two flow rates including conditions corresponding to the 90 percent power level, with jet fuel and methane. Nitrogen Raman spectra are free of band interference. However, the signal levels are lower than expected. Sources of signal losses are discussed. 27 refs.

  3. The hierarchical structure of chemical engineering

    Institute of Scientific and Technical Information of China (English)

    Mooson; KWAUK

    2007-01-01

    Around the turn of the present century,scholars began to recognize chemical engineering as a com-plex system,and have been searching for a convenient point of entry for refreshing its knowledge base.From our study of the dynamic structures of dispersed particles in fluidization and the resultingmulti-scale method,we have been attempting to extend our findings to structures prevailing in othermultiphase systems as well as in the burgeoning industries producing functional materials.Chemicalengineering itself is hierarchically structured.Besides structures based on space and time,such hier-archy could be built from ChE history scaled according to science content,or from ChE operation ac-cording to the expenditure of manpower and capital investment.

  4. Heat transfer in rocket engine combustion chambers and regeneratively cooled nozzles

    Science.gov (United States)

    1993-01-01

    A conjugate heat transfer computational fluid dynamics (CFD) model to describe regenerative cooling in the main combustion chamber and nozzle and in the injector faceplate region for a launch vehicle class liquid rocket engine was developed. An injector model for sprays which treats the fluid as a variable density, single-phase media was formulated, incorporated into a version of the FDNS code, and used to simulate the injector flow typical of that in the Space Shuttle Main Engine (SSME). Various chamber related heat transfer analyses were made to verify the predictive capability of the conjugate heat transfer analysis provided by the FDNS code. The density based version of the FDNS code with the real fluid property models developed was successful in predicting the streamtube combustion of individual injector elements.

  5. A new HVAC system based on cogeneration by an internal combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Lazzarin, R.M [Instituto di Ingegneria Gestionale, Universita di Padova, Vicenza (Italy); Longo, G.A.; Romagnoni, P.C. [Istituto di Fisica Technica, Universita di Padova, Padova (Italy)

    1997-06-01

    A new HVAC system is proposed and studied. The plant consists of a reciprocating internal combustion gas engine, producing electrical energy with heat recovery from the jacket water heat and the exhaust. The electricity serves lighting, emf for the building and individual room reversible air-water heat pumps that satisfy mainly sensible cooling and a fraction of the winter heating load. An open cycle absorption system which treats the primary air meets the summer latent load and year round ventilation requirements. In winter the system operates as an open cycle heat pump. The regeneration of the sorbent is obtained by the internal combustion engine heat recovery. The proposed system is analyzed comparing its performance with a traditional plant both in summer and winter mode. 8 refs.

  6. Cooling system in a rotary piston internal combustion engine. Kuehlsystem einer Rotationskolbenbrennkraftmaschine

    Energy Technology Data Exchange (ETDEWEB)

    Eiermann, D.; Nuber, R.

    1991-05-23

    Cooling system of a trochoid-type rotary piston internal combustion engine with a liquid-cooled casing. First the coolant is conducted isochronically and in parallel through cooling chambers of the jacket and a side part of the casing from where it is transported by a cooling pump through the cooling chambers of the other side part, on past a thermostat and into a cooler positioned on this other side part. The cooler consists of a parallel connected pipe bundle whose finned pipes follow the radial outer contours of the casing of the machine. From the cooler the coolant is conducted back into the cooling chambers of the first side part and the jacket. A blower fitted on the eccentric shaft of the internal combustion engine inside the cooler takes in fresh air axially and discharges it radially through the finned pipes.

  7. A Study of the Theoretical Potential of Thermochemical Exhaust Heat Recuperation for Internal Combustion Engines

    Energy Technology Data Exchange (ETDEWEB)

    Chakravarthy, Veerathu K [ORNL; Daw, C Stuart [ORNL; Pihl, Josh A [ORNL; Conklin, Jim [ORNL

    2010-01-01

    We present a detailed thermodynamic analysis of thermochemical recuperation (TCR) applied to an idealized internal combustion engine with single-stage work extraction. Results for several different fuels are included. For a stoichiometric mixture of methanol and air, TCR can increase the estimated ideal engine Second Law efficiency by about 3% for constant pressure reforming and over 5% for constant volume reforming. For ethanol and isooctane the estimated Second Law efficiency increases for constant volume reforming are 9% and 11%, respectively. The Second Law efficiency improvements from TCR result primarily from the higher intrinsic exergy of the reformed fuel and pressure boost associated with gas mole increase. Reduced combustion irreversibility may also yield benefits for future implementations of combined cycle work extraction.

  8. A Study of the Theoretical Potential of Thermochemical Exhaust Heat Recuperation in Internal Combustion Engines

    Energy Technology Data Exchange (ETDEWEB)

    Daw, C Stuart [ORNL; Pihl, Josh A [ORNL; Chakravarthy, Veerathu K [ORNL; Conklin, Jim [ORNL

    2010-01-01

    A detailed thermodynamic analysis of thermochemical recuperation (TCR) applied to an idealized internal combustion engine with single-stage work extraction is presented. Results for several different fuels are included. For a stoichiometric mixture of methanol and air, TCR can increase the estimated ideal engine second law efficiency by about 3% for constant pressure reforming and over 5% for constant volume reforming. For ethanol and isooctane, the estimated second law efficiency increases for constant volume reforming are 9 and 11%, respectively. The second law efficiency improvements from TCR result primarily from the higher intrinsic exergy of the reformed fuel and pressure boost associated with the gas mole increase. Reduced combustion irreversibility may also yield benefits for future implementations of combined cycle work extraction.

  9. Screening analysis and selection of emission reduction concepts for intermittent combustion aircraft engines

    Science.gov (United States)

    Rezy, B. J.; Meyers, J. E.; Tucker, J. R.; Stuckas, S. J.

    1976-01-01

    An analysis was conducted to screen, evaluate, and select three engine exhaust emission reduction concepts from a group of 14 candidate alternatives. A comprehensive literature search was conducted to survey the emission reduction technology state-of-the-art and establish contact with firms working on intermittent combustion engine development and pollution reduction problems. Concept development, advantages, disadvantages, and expected emission reduction responses are stated. A set of cost effectiveness criteria was developed, appraised for relative importance, and traded off against each concept so that its merit could be determined. A decision model was used to aid the evaluators in managing the criteria, making consistent judgements, calculating merit scores, and ranking the concepts. An Improved Fuel Injection System, Improved Cooling Combustion Chamber, and a Variable Timing Ignition System were recommended to NASA for approval and further concept development. An alternate concept, Air Injection, was also recommended.

  10. Internal combustion engine for vehicles with automatic gearbox. Brennkraftmaschine fuer Kraftfahrzeuge mit einem automatischen Getriebe

    Energy Technology Data Exchange (ETDEWEB)

    Hetmann, R.

    1982-04-19

    The invention refers to an internal combustion engine for vehicles with an automatic gearbox, where the internal combustion engine has a first group of cylinders and at least one second group of cylinders, and a device for affecting the fuel supply to the groups of cylinders, depending on the working parameters of the vehicle. The invention is characterised by the fact that the working parameters are the handbrake and footbrake of the vehicle, and that the device for affecting the fuel supply to the groups of cylinders when the footbrake or handbrake is operated makes it possible to supply fuel to only part of the groups of cylinders. The control switches of both braking systems are connected to the fuel supply control via a logic circuit. This arrangement of the system prevents damage when testing the braking speed of the automatic gearbox due to excessive loads.

  11. Combustion parameters of spark ignition engine using waste potato bioethanol and gasoline blended fuels

    Science.gov (United States)

    Ghobadian, B.; Najafi, G.; Abasian, M.; Mamat, R.

    2015-12-01

    The purpose of this study is to investigate the combustion parameters of a SI engine operating on bioethanol-gasoline blends (E0-E20: 20% bioethanol and 80% gasoline by volume). A reactor was designed, fabricated and evaluated for bioethanol production from potato wastes. The results showed that increasing the bioethanol content in the blend fuel will decrease the heating value of the blended fuel and increase the octane number. Combustion parameters were evaluated and analyzed at different engine speeds and loads (1000-5000 rpm). The results revealed that using bioethanol-gasoline blended fuels will increase the cylinder pressure and its 1st and 2nd derivatives (P(θ), P•(θ) and P••(θ)). Moreover, using bioethanol- gasoline blends will increase the heat release (Q•(θ)) and worked of the cycle. This improvement was due to the high oxygen percentage in the ethanol.

  12. Ethical Standards for Publication in Chinese Journal of Chemical Engineering

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@Chinese Journal of Chemical Engineering is a publication of the Chemical Industry and Engineering Society of China (CIESC) dedicated to present the original contributions of knowledge with permanent value from chemical engineering researcher and technical staff in processing industries in China and the world. The Editors-in-Chief, Associate Editors-in-Chief and Editorial Staff of the journal share the responsibility to maintain the CJChE ethical standards for paper reviewing and handling process.

  13. Assessment of ISLOCA risk-methodology and application to a combustion engineering plant

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, D.L.; Auflick, J.L.; Haney, L.N. [EG and G Idaho, Inc., Idaho Falls, ID (United States)

    1992-04-01

    Inter-system loss-of-coolant accidents (ISLOCAs) have been identified as important contributors to offsite risk for some nuclear power plants. A methodology has been developed for identifying and evaluating plant-specific hardware designs, human factors issues, and accident consequence factors relevant to the estimation of ISOLOCA core damage frequency and risk. This report presents a detailed of description of the application of this analysis methodology to a Combustion Engineering plant.

  14. Invited Review. Combustion instability in spray-guided stratified-charge engines. A review

    Energy Technology Data Exchange (ETDEWEB)

    Fansler, Todd D. [Univ. of Wisconsin, Madison, WI (United States); Reuss, D. L. [Univ. of Michigan, Ann Arbor, MI (United States); Sandia National Lab. (SNL-CA), Livermore, CA (United States); Sick, V. [Univ. of Michigan, Ann Arbor, MI (United States); Dahms, R. N. [Sandia National Lab. (SNL-CA), Livermore, CA (United States)

    2015-02-02

    Our article reviews systematic research on combustion instabilities (principally rare, random misfires and partial burns) in spray-guided stratified-charge (SGSC) engines operated at part load with highly stratified fuel -air -residual mixtures. Results from high-speed optical imaging diagnostics and numerical simulation provide a conceptual framework and quantify the sensitivity of ignition and flame propagation to strong, cyclically varying temporal and spatial gradients in the flow field and in the fuel -air -residual distribution. For SGSC engines using multi-hole injectors, spark stretching and locally rich ignition are beneficial. Moreover, combustion instability is dominated by convective flow fluctuations that impede motion of the spark or flame kernel toward the bulk of the fuel, coupled with low flame speeds due to locally lean mixtures surrounding the kernel. In SGSC engines using outwardly opening piezo-electric injectors, ignition and early flame growth are strongly influenced by the spray's characteristic recirculation vortex. For both injection systems, the spray and the intake/compression-generated flow field influence each other. Factors underlying the benefits of multi-pulse injection are identified. Finally, some unresolved questions include (1) the extent to which piezo-SGSC misfires are caused by failure to form a flame kernel rather than by flame-kernel extinction (as in multi-hole SGSC engines); (2) the relative contributions of partially premixed flame propagation and mixing-controlled combustion under the exceptionally late-injection conditions that permit SGSC operation on E85-like fuels with very low NOx and soot emissions; and (3) the effects of flow-field variability on later combustion, where fuel-air-residual mixing within the piston bowl becomes important.

  15. Mechanical and thermal analysis of the internal combustion engine piston using Ansys

    Science.gov (United States)

    Cioată, V. G.; Kiss, I.; Alexa, V.; Raţiu, S. A.

    2017-01-01

    The piston is one of the most important components of the internal combustion engine. Piston fail mainly due to mechanical stresses and thermal stresses. In this paper is determined by using the finite element method, stress and displacement distribution due the flue gas pressure and temperature, separately and combined. The FEA is performed by CAD and CAE software. The results are compared with those obtained by the analytical method and conclusions have been drawn.

  16. On the wall jet from the ring crevice of an internal combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Cloutman, L.D. [Lawrence Livermore National Lab., CA (United States); Green, R.M. [Sandia National Labs., Livermore, CA (United States)

    1996-05-01

    Numerical simulations and experiments of the jetting of gases from the ring crevices of a laboratory engine shortly after exhaust valve opening showed an unanticipated radial flow of the crevice gases into the main combustion chamber. We report well-resolved numerical simulations of a wall jet that show that this radial motion is driven by vorticity generation in the wall boundary layer and at the corner of the piston crown.

  17. Optimization of a Reduced Chemical Kinetic Model for HCCI Engine Simulations by Micro-Genetic Algorithm

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A reduced chemical kinetic model (44 species and 72 reactions) for the homogeneous charge compression ignition (HCCI) combustion of n-heptane was optimized to improve its autoignition predictions under different engine operating conditions. The seven kinetic parameters of the optimized model were determined by using the combination of a micro-genetic algorithm optimization methodology and the SENKIN program of CHEMKIN chemical kinetics software package. The optimization was performed within the range of equivalence ratios 0.2-1.2, initial temperature 310-375 K and initial pressure 0.1-0.3 MPa. The engine simulations show that the optimized model agrees better with the detailed chemical kinetic model (544 species and 2 446 reactions) than the original model does.

  18. COMBUSTION AND PERFORMANCE CHARACTERISTICS OF A SMALL SPARK IGNITION ENGINE FUELLED WITH HCNG

    Directory of Open Access Journals (Sweden)

    A. SONTHALIA

    2015-04-01

    Full Text Available Due to environmental concerns and fossil fuel depletion, large scale researches were carried out involving the use of natural gas in internal combustion engines. Natural gas is a clean burning fuel that is available from large domestic natural reserve. When it is used as a fuel in SI engines, it reduces emissions to meet EURO-III norms with carburettors and EURO-IV norms with manifold injection. Countries like India with fewer natural fossil fuel reserves depend heavily on oil imported from Middle East Asian countries and on the other hand combustion of fossil fuel has negative impact on air quality in urban areas. Use of CNG as a fuel in internal combustion engines can reduce the intensiveness of these pervasive problems. The performance of CNG can further be improved by addition of small percentages of hydrogen to it to overcome the drawbacks like lower energy density of the fuel, drop in engine power and engine out exhaust emissions. When hydrogen is added to CNG it is called as Hythane or Hydrogen enriched Compressed Natural Gas (HCNG. This can be considered as a first step towards promotion of hydrogen in automobiles. In this study, the effects of mixing hydrogen with CNG on a small air cooled four stroke SI engine’s performance, emissions and heat release rate was analyzed. A comparison of performance and emission by running engine separately on gasoline, hydrogen, CNG and HCNG was done. The results show a significant decrease in HC, CO and NOx emissions and marginal increase in specific energy consumption when fuelled with HCNG.

  19. Improvement of D.I. diesel engine combustion using numerical simulation; Chokufun diesel kikan no nensho kaizen shuho. Suchi kaiseki ni yoru torikumi

    Energy Technology Data Exchange (ETDEWEB)

    Minami, T.; Adachi, T.; Isyii, Y. [Isuzu Motors Ltd., Tokyo (Japan)

    1999-04-01

    For the purpose of improving DI diesel engine combustion, it is important to predict air flow of intake and exhaust manifold, intake port flow, combustion chamber swirl and fuel spray combustion. This paper describes the application of numerical simulation to the engines, the analysis of phenomena and a problem of simulation model modification. (author)

  20. Ethical Standards for Publication in Chinese Journal of Chemical Engineering

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Chinese Journal of Chemical Engineering (CJChE) is a publication of the Chemical Industry and Engineering Society of China (CIESC) dedicated to present the original contributions of knowledge with permanent value from chemical engineering researchers and technical staff of process industries in China and the world. The editors-in-chief, associate editors-in-chief and editorial staff of the journal share the responsibility to maintain the CJChE ethical standards for paper reviewing and handling process. The following ethical standards are thought important to the contributors from Chinese and international chemical engineering communities.

  1. Reduction gear for a turbo compound drive of a supercharged internal combustion engine. Reduktionsgetriebe fuer einen Turbocompoundantrieb einer aufgeladenen Brennkraftmaschine

    Energy Technology Data Exchange (ETDEWEB)

    Bergmann, H.; Fischer, G.; Bueschel, W.

    1991-01-24

    The invention concerns a reduction gear within the turbocompound drive of a supercharged internal combustion engine with at least two reduction stages and a one-way clutch. In order to decouple the vibrations of the turbine and the power plant of the internal combustion engine at least one torsion bushing is provided as which acts as a vibration damper. The one-way clutch is located in the hub of the drive of the second reduction stage in order to save space.

  2. Optical and chemical characterization of aerosols emitted from coal, heavy and light fuel oil, and small-scale wood combustion.

    Science.gov (United States)

    Frey, Anna K; Saarnio, Karri; Lamberg, Heikki; Mylläri, Fanni; Karjalainen, Panu; Teinilä, Kimmo; Carbone, Samara; Tissari, Jarkko; Niemelä, Ville; Häyrinen, Anna; Rautiainen, Jani; Kytömäki, Jorma; Artaxo, Paulo; Virkkula, Aki; Pirjola, Liisa; Rönkkö, Topi; Keskinen, Jorma; Jokiniemi, Jorma; Hillamo, Risto

    2014-01-01

    Particle emissions affect radiative forcing in the atmosphere. Therefore, it is essential to know the physical and chemical characteristics of them. This work studied the chemical, physical, and optical characteristics of particle emissions from small-scale wood combustion, coal combustion of a heating and power plant, as well as heavy and light fuel oil combustion at a district heating station. Fine particle (PM1) emissions were the highest in wood combustion with a high fraction of absorbing material. The emissions were lowest from coal combustion mostly because of efficient cleaning techniques used at the power plant. The chemical composition of aerosols from coal and oil combustion included mostly ions and trace elements with a rather low fraction of absorbing material. The single scattering albedo and aerosol forcing efficiency showed that primary particles emitted from wood combustion and some cases of oil combustion would have a clear climate warming effect even over dark earth surfaces. Instead, coal combustion particle emissions had a cooling effect. Secondary processes in the atmosphere will further change the radiative properties of these emissions but are not considered in this study.

  3. Improvement on Performances of Internal Combustion Engine Using the Technology of Ceramic Coating

    Institute of Scientific and Technical Information of China (English)

    林建生; 付晓光; 张建昭

    2003-01-01

    This paper introduces a new technology of using ceramic coating on piston rings of an internal combustion engine, and the comparison of mechanical efficiency and performances of an actual engine before and after the application of ceramic coating on the piston rings. The experimental results show that the mechanical efficiency and power output are enhanced by 4% and 2.6%, respectively, with fuel consumption reduced by 2.9%. Further studies on coating processing and coating materials as well as the reliability and durability will be of great significance in the application and popularization of the new technology.

  4. Numerical analysis of hydrogen and methane propagation during testing of combustion engines

    Directory of Open Access Journals (Sweden)

    Dvořák V.

    2007-10-01

    Full Text Available The research of gas-fuelled combustion engines using hydrogen or methane require accordingly equipped test benches which take respect to the higher dangerous of self ignition accidents. This article deals with numerical calculations of flow in laboratory during simulated leakage of gas-fuel from fuel system of tested engine. The influences of local suction and influences of roof exhausters on the flow in the laboratory and on the gas propagation are discussed. Results obtained for hydrogen and for methane are compared. Conclusions for design and performance of suction devices and test benches are deduced from these results.

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

    Directory of Open Access Journals (Sweden)

    Rosli A. Bakar

    2009-01-01

    Full Text Available 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 rotational speed varied from 2500 to 4500 rpm while the injector location was considered fixed in the midway of the intake port. The effects of air fuel ratio, crank angle and engine speed are presented in this study. From the acquired results show that the air-fuel ratio and engine speed were greatly influence on the performance of hydrogen fueled engine. It was shown that decreases the Brake Mean Effective Pressure (BMEP and brake thermal efficiency with increases of the engine speed and air-fuel ratio however the increase the Brake Specific Fuel Consumption (BSFC with increases the speed and air-fuel ratio. The cylinder temperature increases with increases of engine speed however temperature decreases with increases of air-fuel ratio. The pressure fluctuations increased substantially with increases of speed at intake port however rise of pressure at the end of the exhaust stroke lead to reverse flow into the cylinder past exhaust valve. The fluctuation amplitude responded to the engine speed in case of exhaust pressure were given less than the intake pressure. The volumetric efficiency increased with increases of engine speed and equivalent ratio. The volumetric efficiency of the hydrogen engines with port injection is a serious problem and reduces the overall performance of the engine. This emphasized the ability of retrofitting the traditional engines with hydrogen fuel with minor modifications.

  6. 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.

  7. A comprehensive study on waste heat recovery from internal combustion engines using organic Rankine cycle

    Directory of Open Access Journals (Sweden)

    Tahani Mojtaba

    2013-01-01

    Full Text Available There are a substantial amount of waste heat through exhaust gas and coolant of an Internal Combustion Engine. Organic Rankine cycle is one of the opportunities in Internal Combustion Engines waste heat recovery. In this study, two different configurations of Organic Rankine cycle with the capability of simultaneous waste heat recovery from exhaust gas and coolant of a 12L diesel engine were introduced: Preheat configuration and Two-stage. First, a parametric optimization process was performed for both configurations considering R-134a, R-123, and R-245fa as the cycle working fluids. The main objective in optimization process was maximization of the power generation and cycle thermal efficiency. Expander inlet pressure and preheating temperature were selected as design parameters. Finally, parameters like hybrid generated power and reduction of fuel consumption were studied for both configurations in different engine speeds and full engine load. It was observed that using R-123 as the working fluid, the best performance in both configurations was obtained and as a result the 11.73% and 13.56% reduction in fuel consumption for both preheat and Two-stage configurations were found respectively.

  8. Influence of the cooling degree upon performances of internal combustion engine

    Science.gov (United States)

    Grǎdinariu, Andrei Cristian; Mihai, Ioan

    2016-12-01

    Up to present, air cooling systems still raise several unsolved problems due to conditions imposed by the environment in terms of temperature and pollution levels. The present paper investigates the impact of the engine cooling degree upon its performances, as important specific power is desired for as low as possible fuel consumption. A technical solution advanced by the authors[1], consists of constructing a bi-flux compressor, which can enhance the engine's performances. The bi-flux axial compressor accomplishes two major functions, that is it cools down the engine and it also turbocharges it. The present paper investigates the temperature changes corresponding to the fresh load, during the use of a bi-flux axial compressor. This compressor is economically simple, compact, and offers an optimal response at low rotational speeds of the engine, when two compression steps are used. The influence of the relative coefficient of air temperature drop upon working agent temperature at the intercooler exit is also investigated in the present work. The variation of the thermal load coefficient by report to the working agent temperature is also investigated during engine cooling. The variation of the average combustion temperature is analyzed in correlation to the thermal load coefficient and the temperatures of the working fluid at its exit from the cooling system. An exergetic analysis was conducted upon the influence of the cooling degree on the motor fluid and the gases resulted from the combustion process.

  9. An Experimental Study of Emission and Combustion Characteristics of Marine Diesel Engine with Fuel Injector Malfunctions

    Directory of Open Access Journals (Sweden)

    Kowalski Jerzy

    2016-01-01

    Full Text Available The presented paper shows the results of the laboratory study on the relation between chosen malfunctions of a fuel injector and composition of exhaust gas from the marine engine. The object of research is a marine 3-cylinder, four-stroke, direct injection diesel engine with an intercooler system. The engine was loaded with a generator and supercharged. The generator was electrically connected to the water resistance. The engine operated with a load between 50 kW and 250 kW at a constant speed. The engine load and speed, parameters of the turbocharger, systems of cooling, fuelling, lubricating and air exchange, were measured. Fuel injection and combustion pressures in all cylinders of the engine were also recorded. Exhaust gas composition was recorded by using a electrochemical gas analyzer. Air pressure, temperature and humidity were also recorded. Emission characteristics of the engine were calculated according to ISO 8178 standard regulations. During the study the engine operated at the technical condition recognized as „working properly” and with simulated fuel injector malfunctions. Simulation of malfunctions consisted in the increasing and decreasing of fuel injector static opening pressure, decalibration of fuel injector holes and clogging 2 neighboring of 9 fuel injector holes on one of 3 engine cylinders.

  10. Emission estimation of neat paradise tree oil combustion assisted with superheated hydrogen in a 4-stroke natural aspirated DICI engine

    Directory of Open Access Journals (Sweden)

    Sundararajan Karthikayan

    2016-01-01

    Full Text Available This research work investigates the use of neat paradise tree oil in a 4-stroke natural aspirated direct injection compression ignition engine assisted with the help of super-heated hydrogen (hydrogen in gaseous state or above its saturation temperature as a combustion improver. The high calorific gaseous fuel hydrogen gas was used as a combustion improver and admitted into the engine during the suction stroke. A 4-stroke single cylinder Diesel engine was chosen and its operating parameters were suitably modified. Neat paradise tree oil was admitted through standard injector of the engine and hydrogen was admitted through induction manifold. Inducted super-heated hydrogen was initiated the intermediate compounds combustion of neat paradise tree oil. This process offers higher temperature combustion and results in complete combustion of heavier molecules of neat paradise tree oil within shorter duration. The results of the experiment reveal that 40% higher NOx, 20% lower smoke, 5% lower CO, and 45% lower HC than that of neat paradise tree oil fuel operation and the admission of superheated hydrogen has improved the combustion characteristics of neat paradise tree oil. The investigation successfully proved that the application of neat paradise tree oil with 15% of hydrogen improver is possible under a regular Diesel engine with minimal engine modification.

  11. Using Simulation to Increase Yields in Chemical Engineering

    OpenAIRE

    William C. Conley

    2003-01-01

    Trying to increase the yields or profit or efficiency (less pollution) of chemical processes is a central goal of the chemical engineer in theory and practice. Certainly sound training in chemistry, business and pollution control help the engineer to set up optimal chemical processes. However, the ever changing demands of customers and business conditions, plus the multivariate complexity of the chemical business can make optimization challenging. Mathematical tools such as statistics and lin...

  12. Maximizing Power Output in Homogeneous Charge Compression Ignition (HCCI) Engines and Enabling Effective Control of Combustion Timing

    Science.gov (United States)

    Saxena, Samveg

    Homogeneous Charge Compression Ignition (HCCI) engines are one of the most promising engine technologies for the future of energy conversion from clean, efficient combustion. HCCI engines allow high efficiency and lower CO2 emission through the use of high compression ratios and the removal of intake throttle valves (like Diesel), and allow very low levels of urban pollutants like nitric oxide and soot (like Otto). These engines, however, are not without their challenges, such as low power density compared with other engine technologies, and a difficulty in controlling combustion timing. This dissertation first addresses the power output limits. The particular strategies for enabling high power output investigated in this dissertation focus on avoiding five critical limits that either damage an engine, drastically reduce efficiency, or drastically increase emissions: (1) ringing limits, (2) peak in-cylinder pressure limits, (3) misfire limits, (4) low intake temperature limits, and (5) excessive emissions limits. The research shows that the key factors that enable high power output, sufficient for passenger vehicles, while simultaneously avoiding the five limits defined above are the use of: (1) high intake air pressures allowing improved power output, (2) highly delayed combustion timing to avoid ringing limits, and (3) using the highest possible equivalence ratio before encountering ringing limits. These results are revealed by conducting extensive experiments spanning a wide range of operating conditions on a multi-cylinder HCCI engine. Second, this dissertation discusses strategies for effectively sensing combustion characteristics on a HCCI engine. For effective feedback control of HCCI combustion timing, a sensor is required to quantify when combustion occurs. Many laboratory engines use in-cylinder pressure sensors but these sensors are currently prohibitively expensive for wide-scale commercialization. Instead, ion sensors made from inexpensive sparkplugs

  13. Development of combustion management concept for natural-aspirated small diesel engine; Shizen kyuki kogata diesel engine no nensho seigyo concept no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Wada, T.; Kawano, T.; Shoji, M.; Kuniyosh, M.; Yamashita, O.; Nagao, A. [Mazda Motor Corp., Tokyo (Japan); Yoshikawa, S. [Zexel Corp., Tokyo (Japan)

    1997-10-01

    We have developed a combustion management concept for natural-aspirated small IDI diesel engines and achieved higher power, lower exhaust emissions and more comfort. The concept is related to improvements of intake volumetric efficiency, EGR effect, mixture formation caused by combustion chamber and spray characteristics, engine management system and after treatment device. This paper describes the concept and experimental results. 3 refs., 14 figs., 1 tab.

  14. Carbon stripping - a critical process step in chemical looping combustion of solid fuels

    Energy Technology Data Exchange (ETDEWEB)

    Kramp, M.; Thon, A.; Hartge, E.U.; Heinrich, S.; Werther, J. [Hamburg University of Technology, Institute of Solids Process Engineering and Particle Technology, Hamburg (Germany)

    2012-03-15

    In chemical looping combustion of solid fuels the well-mixed solids flow from the fuel reactor consisting of char, ash, and oxygen carrier particles cannot be completely separated into its constituents before it enters the air reactor. The slip of carbon will thus lead to char oxidation in the wrong reactor. Process simulation was applied to investigate the carbon stripping process in chemical looping combustion of solid fuels. Depending on the fuel choice, without carbon stripping CO{sub 2} capture rates below 50 % are calculated for 4 min of solids residence time in the fuel reactor. In a process with carbon stripper, however, CO{sub 2} capture rates exceeding 90 % can be achieved for both fuels investigated in this work. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  15. The problems of piston skirt microgeometry in combustion engines

    Science.gov (United States)

    Iskra, A.; Babiak, M.; Wróblewski, E.

    2016-09-01

    Geometry of the slot between piston bearing surface and cylinder bore affects the friction losses of the IC engine to the far extent. It appears that these losses depend more on the area covered with oil than the thickness of oil layer separating collaborating parts. Barrel-shaped or stepwise piston bearing surface is the way to reduce the oil covered area. Turns out that the referred to friction losses contributes more to area covered by the oil film than the film thickness of the separation elements cooperating. The method to reduce the area covered by the oil film is a modification of the bearing surface of the piston by adjusting the profile. This paper presents the results of simulation leading to the reduction in friction losses and abrasive wear of piston bearing surface and cylinder bore. Covering the piston bearing surface with a thin layer of graphite one can get an extremely advantageous tribological properties of the piston assembly which means the expected parameters of oil film and in a case of film rupture-an ignorable abrasive wear of the graphite layer and/or cylinder bore.

  16. Combustion Control System Design of Diesel Engine via ASPR based Output Feedback Control Strategy with a PFC

    Science.gov (United States)

    Mizumoto, Ikuro; Tsunematsu, Junpei; Fujii, Seiya

    2016-09-01

    In this paper, a design method of an output feedback control system with a simple feedforward input for a combustion model of diesel engine will be proposed based on the almost strictly positive real-ness (ASPR-ness) of the controlled system for a combustion control of diesel engines. A parallel feedforward compensator (PFC) design scheme which renders the resulting augmented controlled system ASPR will also be proposed in order to design a stable output feedback control system for the considered combustion model. The effectiveness of our proposed method will be confirmed through numerical simulations.

  17. Analysis of Thermal and Chemical Effets on Negative Valve Overlap Period Energy Recovery for Low-Temperature Gasoline Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Ekoto, Dr Isaac [Sandia National Laboratories (SNL); Peterson, Dr. Brian [University of Edinburgh; Szybist, James P [ORNL; Northrop, Dr. William [University of Minnesota

    2015-01-01

    A central challenge for efficient auto-ignition controlled low-temperature gasoline combustion (LTGC) engines has been achieving the combustion phasing needed to reach stable performance over a wide operating regime. The negative valve overlap (NVO) strategy has been explored as a way to improve combustion stability through a combination of charge heating and altered reactivity via a recompression stroke with a pilot fuel injection. The study objective was to analyze the thermal and chemical effects on NVO-period energy recovery. The analysis leveraged experimental gas sampling results obtained from a single-cylinder LTGC engine along with cylinder pressure measurements and custom data reduction methods used to estimate period thermodynamic properties. The engine was fueled by either iso-octane or ethanol, and operated under sweeps of NVO-period oxygen concentration, injection timing, and fueling rate. Gas sampling at the end of the NVO period was performed via a custom dump-valve apparatus, with detailed sample speciation by in-house gas chromatography. The balance of NVO-period input and output energy flows was calculated in terms of fuel energy, work, heat loss, and change in sensible energy. Experiment results were complemented by detailed chemistry single-zone reactor simulations performed at relevant mixing and thermodynamic conditions, with results used to evaluate ignition behavior and expected energy recovery yields. For the intermediate bulk-gas temperatures present during the NVO period (900-1100 K), weak negative temperature coefficient behavior with iso-octane fueling significantly lengthened ignition delays relative to similar ethanol fueled conditions. Faster ethanol ignition chemistry led to lower recovered fuel intermediate yields relative to similar iso-octane fueled conditions due to more complete fuel oxidation. From the energy analysis it was found that increased NVO-period global equivalence ratio, either from lower NVOperiod oxygen

  18. Numerical simulation of charge stratifications to improve combustion and NO formation of lean-burn SI engines

    Institute of Scientific and Technical Information of China (English)

    Zhijun PENG

    2009-01-01

    The influences of charge stratification on spark ignition (SI) engine combustion and NO emission were analyzed using a phenomenological model. The mixture in the cylinder was divided spherically into three parts: a central core with a stoichiometric air-fuel charge, a dilution region without any combustible charge, and a mixing region lying between the core and the dilution region.Three mixture stratification parameters such as the extent of dilution in the mixing region, the extent of combustible charge in the mixing region, and the gradient of stratification in the mixing region were investigated. The results indicate that the extent of combustible charge in the mixing region could reduce in-cylinder NO formation significantly, compared with the extent of dilution in the mixing region. As long as the degree of dilution in the mixing region is within the dilution limit of the combustible charge, the gradient of dilution has little effect on combustion and NO formation.

  19. High Thermal Conductivity NARloy-Z-Diamond Composite Combustion Chamber Liner For Advanced Rocket Engines

    Science.gov (United States)

    Bhat, Biliyar N.; Ellis, David; Singh, Jogender

    2014-01-01

    Advanced high thermal conductivity materials research conducted at NASA Marshall Space Flight Center (MSFC) with state of the art combustion chamber liner material NARloy-Z showed that its thermal conductivity can be increased significantly by adding diamond particles and sintering it at high temperatures. For instance, NARloy-Z containing 40 vol. percent diamond particles, sintered at 975C to full density by using the Field assisted Sintering Technology (FAST) showed 69 percent higher thermal conductivity than baseline NARloy-Z. Furthermore, NARloy-Z-40vol. percent D is 30 percent lighter than NARloy-Z and hence the density normalized thermal conductivity is 140 percent better. These attributes will improve the performance and life of the advanced rocket engines significantly. By one estimate, increased thermal conductivity will directly translate into increased turbopump power up to 2X and increased chamber pressure for improved thrust and ISP, resulting in an expected 20 percent improvement in engine performance. Follow on research is now being conducted to demonstrate the benefits of this high thermal conductivity NARloy-Z-D composite for combustion chamber liner applications in advanced rocket engines. The work consists of a) Optimizing the chemistry and heat treatment for NARloy-Z-D composite, b) Developing design properties (thermal and mechanical) for the optimized NARloy-Z-D, c) Fabrication of net shape subscale combustion chamber liner, and d) Hot fire testing of the liner for performance. FAST is used for consolidating and sintering NARlo-Z-D. The subscale cylindrical liner with built in channels for coolant flow is also fabricated near net shape using the FAST process. The liner will be assembled into a test rig and hot fire tested in the MSFC test facility to determine performance. This paper describes the development of this novel high thermal conductivity NARloy-Z-D composite material, and the advanced net shape technology to fabricate the combustion

  20. Control of homogeneous charge compression ignition combustion in a two-cylinder gasoline direct injection engine with negative valve overlap

    Institute of Scientific and Technical Information of China (English)

    WANG Zhi; WANG Jianxin; SHUAI Shijin; MA Qingjun; TIAN Guohong

    2007-01-01

    Homogeneous charge compression ignition(HCCI) has challenges in ignition timing control,combustion rate control,and operating range extension.In this paper,HCCI combustion was studied in a two-cylinder gasoline direct injection (GDI) engine with negative valve overlap (NVO).A two-stage gasoline direct injection strategy combined with negative valve overlap was used to control mixture formation and combustion.The gasoline engine could be operated in HCCI combustion mode at a speed range of 800-2 200 r/min and load,indicated mean effective pressure (IMEP) range of 0.1-0.53 MPa.The engine fuel consumption 4× 10-5 without soot emission.The effect of different injection strategies on HCCI combustion was studied.The experimental results indicated that the coefficient of variation of the engine cycle decreased by using NVO with two-stage direct injection;the ignition timing and combustion rate could be controlled;and the operational range of HCCI combustion could be extended.

  1. Experimental investigation of gasoline compression ignition combustion in a light-duty diesel engine

    Science.gov (United States)

    Loeper, C. Paul

    Due to increased ignition delay and volatility, low temperature combustion (LTC) research utilizing gasoline fuel has experienced recent interest [1-3]. These characteristics improve air-fuel mixing prior to ignition allowing for reduced emissions of nitrogen oxides (NOx) and soot (or particulate matter, PM). Computational fluid dynamics (CFD) results at the University of Wisconsin-Madison's Engine Research Center (Ra et al. [4, 5]) have validated these attributes and established baseline operating parameters for a gasoline compression ignition (GCI) concept in a light-duty diesel engine over a large load range (3-16 bar net IMEP). In addition to validating these computational results, subsequent experiments at the Engine Research Center utilizing a single cylinder research engine based on a GM 1.9-liter diesel engine have progressed fundamental understanding of gasoline autoignition processes, and established the capability of critical controlling input parameters to better control GCI operation. The focus of this thesis can be divided into three segments: 1) establishment of operating requirements in the low-load operating limit, including operation sensitivities with respect to inlet temperature, and the capabilities of injection strategy to minimize NOx emissions while maintaining good cycle-to-cycle combustion stability; 2) development of novel three-injection strategies to extend the high load limit; and 3) having developed fundamental understanding of gasoline autoignition kinetics, and how changes in physical processes (e.g. engine speed effects, inlet pressure variation, and air-fuel mixture processes) affects operation, develop operating strategies to maintain robust engine operation. Collectively, experimental results have demonstrated the ability of GCI strategies to operate over a large load-speed range (3 bar to 17.8 bar net IMEP and 1300-2500 RPM, respectively) with low emissions (NOx and PM less than 1 g/kg-FI and 0.2 g/kg-FI, respectively), and low

  2. Computational Investigation of Combustion Instabilities in a Laboratory-Scale LDI Gas Turbine Engine

    Science.gov (United States)

    2013-06-01

    Westbrook and F. L. Dryer, "Simplified Reaction -Mechanisms for the Oxidation of Hydrocarbon Fudels in Flames," Combustion Science and Technology, vol...is also studied in order to understand the change of flow characteristics due to chemical reactions and longitudinal acoustics. The major mode shapes...density, velocity vector and pressure respectively; h0 is the stagnation enthalpy and Y is a species mass fraction vector; K represents the turbulence

  3. A Case Study of Search Engine on World Wide Web for Chemical Fiber Engineering

    Institute of Scientific and Technical Information of China (English)

    张利; 邵世煌; 曾献辉; 尹美华

    2001-01-01

    Search engine is an effective approach to promote the service quality of the World Wide Web. On terms of the analysis of search engines at home and abroad, the developing principle of search engines is given according to the requirement of Web information for chemical fiber engineering. The implementation method for the communication and dynamic refreshment of information on home page of the search engines are elaborated by using programming technology of Active Server Page 3.0 (ASP3.0). The query of chemical fiber information and automatic linking of chemical fiber Web sites can be easily realized by the developed search engine under Internet environment according to users' requirement.

  4. Chemical Engineering Data Analysis Made Easy with DataFit

    Science.gov (United States)

    Brenner, James R.

    2006-01-01

    The outline for half of a one-credit-hour course in analysis of chemical engineering data is presented, along with a range of typical problems encountered later on in the chemical engineering curriculum that can be used to reinforce the data analysis skills learned in the course. This mini course allows students to be exposed to a variety of ChE…

  5. Enhancing the Undergraduate Computing Experience in Chemical Engineering CACHE Corporation

    Science.gov (United States)

    Edgar, Thomas F.

    2006-01-01

    This white paper focuses on the integration and enhancement of the computing experience for undergraduates throughout the chemical engineering curriculum. The computing experience for undergraduates in chemical engineering should have continuity and be coordinated from course to course, because a single software solution is difficult to achieve in…

  6. Introducing DAE Systems in Undergraduate and Graduate Chemical Engineering Curriculum

    Science.gov (United States)

    Mandela, Ravi Kumar; Sridhar, L. N.; Rengaswamy, Raghunathan

    2010-01-01

    Models play an important role in understanding chemical engineering systems. While differential equation models are taught in standard modeling and control courses, Differential Algebraic Equation (DAE) system models are not usually introduced. These models appear naturally in several chemical engineering problems. In this paper, the introduction…

  7. Results of the 2010 Survey on Teaching Chemical Reaction Engineering

    Science.gov (United States)

    Silverstein, David L.; Vigeant, Margot A. S.

    2012-01-01

    A survey of faculty teaching the chemical reaction engineering course or sequence during the 2009-2010 academic year at chemical engineering programs in the United States and Canada reveals change in terms of content, timing, and approaches to teaching. The report consists of two parts: first, a statistical and demographic characterization of the…

  8. Brewing as a Comprehensive Learning Platform in Chemical Engineering

    Science.gov (United States)

    Nielsen, Rudi P.; Sørensen, Jens L.; Simonsen, Morten E.; Madsen, Henrik T.; Muff, Jens; Strandgaard, Morten; Søgaard, Erik G.

    2016-01-01

    Chemical engineering is mostly taught using traditional classroom teaching and laboratory experiments when possible. Being a wide discipline encompassing topics such as analytical chemistry, process design, and microbiology, it may be argued that brewing of beer has many relations to chemical engineering topic-wise. This work illustrates how…

  9. Semiconductor Chemical Reactor Engineering and Photovoltaic Unit Operations.

    Science.gov (United States)

    Russell, T. W. F.

    1985-01-01

    Discusses the nature of semiconductor chemical reactor engineering, illustrating the application of this engineering with research in physical vapor deposition of cadmium sulfide at both the laboratory and unit operations scale and chemical vapor deposition of amorphous silicon at the laboratory scale. (JN)

  10. Frontiers in Chemical Engineering. Research Needs and Opportunities.

    Science.gov (United States)

    National Academy of Sciences - National Research Council, Washington, DC. Commission on Physical Sciences, Mathematics, and Resources.

    Chemical engineers play a key role in industries such as petroleum, food, artificial fibers, petrochemicals, plastics and many others. They are needed to tailor manufacturing technology to the requirements of products and to integrate product and process design. This report discusses how chemical engineers are continuing to address technological…

  11. THEORETICAL CHEMICAL ENGINEERING - Modeling and Simulation by Christo Boyadjiev

    Directory of Open Access Journals (Sweden)

    Simeon Oka

    2010-01-01

    Full Text Available Book Title: THEORETICAL CHEMICAL ENGINEERING - Modeling and Simulation Author(s: Christo Boyadjiev Institute of Chemical Engineering, Bulgarian Academy of Science, Sofia Publisher: Springer, 2010 ISBN: 978-3-642-10777-1 Review by: Prof. Simeon Oka, Ph. D., Scientific advisor - retired

  12. Resonance vibrations of cylinder charge of Diesel engines and their importance for combustion noise. Resonanzschwingungen der Zylinderladung von Dieselmotoren und ihre Bedeutung fuer das Verbrennungsgeraeusch

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, M.H.

    1987-09-10

    Measurements of the pressure distribution in the gas charge of the combustion space were made on Diesel engines, in a combustion chamber and on a test rig. They describe the significance of inherent resonance vibrations of the gas charge for Diesel engine combustion and for engine acoustics. There are reports on the known principal conditions (inherent vibration pressure amplitude, degree of excitation, combination of several part combustion chambers, wavelengths, phase position) and on the digital analysis (computer-aided) of combustion space inherent vibrations. Data are given on part components of engine noise, possible excitation by pressure variations in the cylinder charge, the theory of combustion space resonance vibration, the conversion of gas pressure variations into combustion noise and investigations on the running engine. (HWJ).

  13. Lean-Burn Cogeneration Biogas Engine with Unscavenged Combustion Prechamber: Comparison with Natural Gas

    Directory of Open Access Journals (Sweden)

    Roger Röthlisberger

    2002-12-01

    Full Text Available Gaseous fuels produced, for example, by waste or agricultural by-products fermentation (biogas can be burned in-situ by cogeneration systems like spark-ignition internal combustion engines. However, the more and more stringent legislation for exhaust gas emissions requires improvement of the combustion process particularly when catalytic after treatment is not reliable as in the case of sewage or landfill biogas. The system proposed in this paper is the use of an unscavenged combustion prechamber instead of direct ignition on a turbocharged 6 cylinder 150 kW gas engine. This prechamber is used for operation with a simulated biogas (40% CO2 in natural gas. The results show that, compared to natural gas operation for the same rated power output of 150 kW and the same NOx emissions, the CO emissions are reduced by 15% and the HC emissions at least by 8%. Efficiencies higher than 36% are achieved which is very promising and the lower CO emissions give a margin to consider an increase of compression ratio.

  14. Evaluation of direct combustion chamber information in internal combustion engines using methods of estimation theory; Auswertung direkter Brennrauminformationen am Verbrennungsmotor mit estimationstheoretischen Methoden

    Energy Technology Data Exchange (ETDEWEB)

    Hart, M.

    1999-04-16

    The estimation of the air mass in the cylinder of a spark ignition (SI) engine is crucial in order to regulate the exact air fuel (A/F) ratio for the catalyst and thus minimize the emissions. Conventional algorithms for estimating the air mass are based on sensor information measured in front of the throttle or in the manifold. Thus, the determination of cylinder individual sizes, particularly the air mass, is impossible. In this work, new sensors, which provide cylinder individual information are investigated and the air mass in each individual cylinder is calculated with adaptive, model based algorithms. Sensors within the combustion chamber of an SI engine enable a cylinder specific evaluation of the thermodynamic work process. In particular, the combustion pressure sensor or ionisation current sensing are two independent methods of measuring direct combustion information. In a few cases such sensors are used in mass production cars. The combustion pressure sensor exhibits two significant advantages when compared to ionisation current. First, it provides information of the pressure in the cylinder during the complete working cycle of the engine and this pressure information is a measure of the entire combustion chamber. In contrast, the ionisation sensing represents a local measurement during the combustion and part of the expansion phase and this measurement can only be seen as a part of the information contained in the combustion pressure sensor signal. Second, the determination of the air mass in the cylinder, the most significant process information, can only be determined by cylinder pressure measurements and not by ionisation current. Reducing costs by eliminating the mass air flow meter is a requirement for the implementation of combustion pressure sensors in a mass production throttled SI engine. Thus, the cylinder pressure sensor must be able to determine the air mass in the cylinder. However, the cylinder pressure sensors will not be implemented in a

  15. Modeling of heat release and emissions from droplet combustion of multi component fuels in compression ignition engines

    OpenAIRE

    Ivarsson, Anders; Schramm, Jesper

    2010-01-01

    This PhD dissertation was carried out at the Technical University of Denmark in Department of Mechanical Engineering and supervised by Associate Professor Jesper Schramm. The PhD project was funded by the Technical University of Denmark. Demands on reducing the fuel consumption and harmful emissions from the compression ignition engines (CI engines or diesel engines) are continuously increased. To comply with this, better modeling tools for the diesel combustion process are desired from the e...

  16. The chemical transformation of calcium in Shenhua coal during combustion in a muffle furnace

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Sida [North China Electric Power Univ., Beijing (China). School of Energy, Power and Mechanical Engineering; Ministry of Education, Beijing (China). Key Lab. of Condition Monitoring and Control for Power Plant Equipment; Zhuo, Yuqun; Chen, Changhe [Tsinghua Univ., Beijing (China). Dept. of Thermal Engineering; Ministry of Education, Beijing (China). Key Lab. for Thermal Science and Power Engineering; Shu, Xinqian [China Univ. of Mining and Technology, Beijing (China). School of Chemical and Environmental Engineering

    2013-07-01

    The chemical reaction characteristics of calcium in three samples of Shenhua coal, i.e. raw sample, hydrochloric acid washed sample and hydrochloric acid washed light fraction, during combustion in a muffle furnace have been investigated in this paper. Ca is bound by calcite and organic matter in Shenhua coal. X ray diffraction (XRD) phase analysis has been conducted to these samples' combustion products obtained by heating at different temperatures. It has been found that the organically-bound calcium could easily react with clays and transform into gehlenite and anorthite partially if combusted under 815 C, whilst the excluded minerals promoted the conversion of gehlenite to anorthite. Calcite in Shenhua coal decomposed into calcium oxide and partially transformed into calcium sulfate under 815 C, and formed gehlenite and anorthite under 1,050 C. Calcite and other HCl-dissolved minerals in Shenhua coal were responsible mainly for the characteristic that the clay minerals in Shenhua coal hardly became mullite during combustion.

  17. Chemical engineering design of CO oxidation catalysts

    Science.gov (United States)

    Herz, Richard K.

    1987-01-01

    How a chemical reaction engineer would approach the challenge of designing a CO oxidation catalyst for pulsed CO2 lasers is described. CO oxidation catalysts have a long history of application, of course, so it is instructive to first consider the special requirements of the laser application and then to compare them to the characteristics of existing processes which utilize CO oxidation catalysts. All CO2 laser applications require a CO oxidation catalyst with the following characteristics: (1) active at stoichiometric ratios of O2 and CO, (2) no inhibition by CO2 or other components of the laser environment, (3) releases no particulates during vibration or thermal cycling, and (4) long lifetime with a stable activity. In all applications, low consumption of power is desirable, a characteristic especially critical in aerospace applications and, thus, catalyst activity at low temperatures is highly desirable. High power lasers with high pulse repetition rates inherently require circulation of the gas mixture and this forced circulation is available for moving gas past the catalyst. Low repetition rate lasers, however, do not inherently require gas circulation, so a catalyst that did not require such circulation would be favorable from the standpoint of minimum power consumption. Lasers designed for atmospheric penetration of their infrared radiation utilize CO2 formed from rare isotopes of oxygen and this application has the additional constraint that normal abundance oxygen isotopes in the catalyst must not exchange with rare isotopes in the gas mixture.

  18. Multiscale computation from a chemical engineering perspective

    Institute of Scientific and Technical Information of China (English)

    Li Jinghai

    2014-01-01

    This-paper-mainly-discusses-the-multiscale-computation-from-a-chemical-engineering-perspective.-From-the-application-designer’s-perspective,we-propose-a-new-approach-to-investigate-and-develop-both-flexi-ble-and-efficient-computer-architectures.-Based-on-the-requirements-of-applications-within-one-category,we-first-induce-and-extract-some-inherent-computing-patterns-or-core-computing-kernels-from-the-applications.-Some-computing-models-and-innovative-computing-architectures-will-then-be-developed-for-these-patterns-or-kernels,as-well-as-the-software-mapping-techniques.-Finally-those-applications-which-can-share-and-utilize-those-computing-patterns-or-kernels-can-be-executed-very-efficiently-on-those-novel-computing-architectures.-We-think-that-the-proposed-approach-may-not-be-achievable-within-the-existing-technology.-However,we-believe-that-it-will-be-available-in-the-near-future.-Hence,we-will-describe-this-approach-from-the-following-four-as-pects:multiscale-environment-in-the-world,-mesoscale-as-a-key-scale,-energy-minimization-multiscale-(EMMS)paradigm-and-our-perspective.

  19. Thermodynamics an advanced textbook for chemical engineers

    CERN Document Server

    Astarita, Gianni

    1989-01-01

    If a Writer would know how to behave himself with relation to Posterity; let him consider in old Books, what he finds, that he is glad to know; and what Omissions he most laments. Jonathan Swift This book emerges from a long story of teaching. I taught chemical engineering thermodynamics for about ten years at the University of Naples in the 1960s, and I still remember the awkwardness that I felt about any textbook I chose to consider-all of them seemed to be vague at best, and the standard of logical rigor seemed immensely inferior to what I could find in books on such other of the students in my first class subjects as calculus and fluid mechanics. One (who is now Prof. F. Gioia of the University of Naples) once asked me a question which I have used here as Example 4. 2-more than 20 years have gone by, and I am still waiting for a more intelligent question from one of my students. At the time, that question compelled me to answer in a way I didn't like, namely "I'll think about it, and I hope I'll have the ...

  20. Blind source separation of internal combustion engine piston slap from other measured vibration signals

    Science.gov (United States)

    Liu, Xianhua; Randall, R. B.

    2005-11-01

    Internal combustion engines have several vibration sources, such as combustion, fuel injection, piston slap and valve operation. For machine condition monitoring or design improvement purposes, it is necessary to separate the vibration signals caused by different sources and then analyse each of them individually. However, traditional frequency analysis techniques are not very useful due to overlap of the different sources over a wide frequency range. This paper attempts to separate the vibration sources, especially piston slap, by using blind source separation techniques with the intention of revealing the potential of the new technique for solving mechanical vibration problems. The BSS method and the Blind least mean square algorithm using Gray's variable norm as a measure of non-Gaussianity of the sources is briefly described and separation results for both simulated and measured data are presented and discussed.