Study of Fuel Air Mixture Formation Process in Spark Ignition Engines PDF Download

Author: Gang Chen
Publisher:
ISBN:
Category :
Languages : en
Pages : 332

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Author: Hans Peter Lenz
Publisher: Springer
ISBN: 148992762X
Category : Technology & Engineering
Languages : en
Pages : 417

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Book Description
Twentyfour years have gone by since the publication of K. Lohner and H. Muller's comprehen sive work "Gemischbildung und Verbrennung im Ottomotor" in 1967 [1.1]' Naturally, the field of mixture formation and combustion in the spark-ignition engine has wit nessed great technological advances and many new findings in the intervening years, so that the time seemed ripe for presenting a summary of recent research and developments. There fore, I gladly took up the suggestion of the editors of this series of books, Professor Dr. H. List and Professor Dr. A. Pischinger, to write a book summarizing the present state of the art. A center of activity of the Institute of Internal-Combustion Engines and Automotive Engineering at the Vienna Technical University, which I am heading, is the field of mixture formation -there fore, many new results that have been achieved in this area in collaboration with the respective industry have been included in this volume. The basic principles of combustion are discussed only to that extent which seemect necessary for an understanding of the effects of mixture formation. The focal point of this volume is the mixture formation in spark-ignition engines, covering both the theory and actual design of the mixture formation units and appropriate intake manifolds. Also, the related measurement technology is explained in this work.

Author: Günter P. Merker
Publisher: Springer Science & Business Media
ISBN: 3642140947
Category : Technology & Engineering
Languages : en
Pages : 660

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Combustion Engines Development nowadays is based on simulation, not only of the transient reaction of vehicles or of the complete driveshaft, but also of the highly unsteady processes in the carburation process and the combustion chamber of an engine. Different physical and chemical approaches are described to show the potentials and limits of the models used for simulation.

Author: F. Zhao
Publisher: Elsevier
ISBN: 008055279X
Category : Technology & Engineering
Languages : en
Pages : 129

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Book Description
The process of fuel injection, spray atomization and vaporization, charge cooling, mixture preparation and the control of in-cylinder air motion are all being actively researched and this work is reviewed in detail and analyzed. The new technologies such as high-pressure, common-rail, gasoline injection systems and swirl-atomizing gasoline fuel injections are discussed in detail, as these technologies, along with computer control capabilities, have enabled the current new examination of an old objective; the direct-injection, stratified-charge (DISC), gasoline engine. The prior work on DISC engines that is relevant to current GDI engine development is also reviewed and discussed. The fuel economy and emission data for actual engine configurations have been obtained and assembled for all of the available GDI literature, and are reviewed and discussed in detail. The types of GDI engines are arranged in four classifications of decreasing complexity, and the advantages and disadvantages of each class are noted and explained. Emphasis is placed upon consensus trends and conclusions that are evident when taken as a whole; thus the GDI researcher is informed regarding the degree to which engine volumetric efficiency and compression ratio can be increased under optimized conditions, and as to the extent to which unburned hydrocarbon (UBHC), NOx and particulate emissions can be minimized for specific combustion strategies. The critical area of GDI fuel injector deposits and the associated effect on spray geometry and engine performance degradation are reviewed, and important system guidelines for minimizing deposition rates and deposit effects are presented. The capabilities and limitations of emission control techniques and after treatment hardware are reviewed in depth, and a compilation and discussion of areas of consensus on attaining European, Japanese and North American emission standards presented. All known research, prototype and production GDI engines worldwide are reviewed as to performance, emissions and fuel economy advantages, and for areas requiring further development. The engine schematics, control diagrams and specifications are compiled, and the emission control strategies are illustrated and discussed. The influence of lean-NOx catalysts on the development of late-injection, stratified-charge GDI engines is reviewed, and the relative merits of lean-burn, homogeneous, direct-injection engines as an option requiring less control complexity are analyzed.

Author: Hans P. Lenz
Publisher: Springer
ISBN: 9783709166932
Category : Technology & Engineering
Languages : en
Pages : 400

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Book Description
Twentyfour years have gone by since the publication of K. Lohner and H. MOiler's comprehen sive work "Gemischbildung und Verbrennung im Ottomotor" in 1967 [1.1]. Naturally, the field of mixture formation and combustion in the spark-ignition engine has wit nessed great technological advances and many new findings in the intervening years, so that the time seemed ripe for presenting a summary of recent research and developments. There fore, I gladly took up the suggestion of the editors of this series of books, Professor Dr. H. List and Professor Dr. A. Pischinger, to write a book summarizing the present state of the art. A center of activity of the Institute of Internal-Combustion Engines and Automotive Engineering at the Vienna Technical University, which I am heading, is the field of mixture formation -there fore, many new results that have been achieved in this area in collaboration with the respective industry have been included in this volume. The basic principles of combustion are discussed only to that extent which seemed necessary for an understanding of the effects of mixture formation. The focal point of this volume is the mixture formation in spark-ignition engines, covering both the theory and actual design of the mixture formation units and appropriate intake manifolds. Also, the related measurement technology is explained in this work.

Author: National Research Council
Publisher: National Academies Press
ISBN: 0309216389
Category : Science
Languages : en
Pages : 373

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Book Description
Various combinations of commercially available technologies could greatly reduce fuel consumption in passenger cars, sport-utility vehicles, minivans, and other light-duty vehicles without compromising vehicle performance or safety. Assessment of Technologies for Improving Light Duty Vehicle Fuel Economy estimates the potential fuel savings and costs to consumers of available technology combinations for three types of engines: spark-ignition gasoline, compression-ignition diesel, and hybrid. According to its estimates, adopting the full combination of improved technologies in medium and large cars and pickup trucks with spark-ignition engines could reduce fuel consumption by 29 percent at an additional cost of $2,200 to the consumer. Replacing spark-ignition engines with diesel engines and components would yield fuel savings of about 37 percent at an added cost of approximately $5,900 per vehicle, and replacing spark-ignition engines with hybrid engines and components would reduce fuel consumption by 43 percent at an increase of $6,000 per vehicle. The book focuses on fuel consumption-the amount of fuel consumed in a given driving distance-because energy savings are directly related to the amount of fuel used. In contrast, fuel economy measures how far a vehicle will travel with a gallon of fuel. Because fuel consumption data indicate money saved on fuel purchases and reductions in carbon dioxide emissions, the book finds that vehicle stickers should provide consumers with fuel consumption data in addition to fuel economy information.

Author: Yoshishige Ohyama
Publisher:
ISBN:
Category : Automotive sensors
Languages : en
Pages : 11

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Author: Suzanne Caulfield
Publisher:
ISBN: 9780549014560
Category : Fluid dynamics
Languages : en
Pages : 102

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In an effort to understand the fluid dynamics in the droplet formation process, during the fuel delivery portion of operation of a small spark ignition engine, a computational study of the process was undertaken. A combination of high-speed photography and Computational Fluid Dynamics was used to investigate the droplet formation process.

Author: Carsten Baumgarten
Publisher: Springer Science & Business Media
ISBN: 3540308369
Category : Technology & Engineering
Languages : en
Pages : 312

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Book Description
A systematic control of mixture formation with modern high-pressure injection systems enables us to achieve considerable improvements of the combustion pr- ess in terms of reduced fuel consumption and engine-out raw emissions. However, because of the growing number of free parameters due to more flexible injection systems, variable valve trains, the application of different combustion concepts within different regions of the engine map, etc., the prediction of spray and m- ture formation becomes increasingly complex. For this reason, the optimization of the in-cylinder processes using 3D computational fluid dynamics (CFD) becomes increasingly important. In these CFD codes, the detailed modeling of spray and mixture formation is a prerequisite for the correct calculation of the subsequent processes like ignition, combustion and formation of emissions. Although such simulation tools can be viewed as standard tools today, the predictive quality of the sub-models is c- stantly enhanced by a more accurate and detailed modeling of the relevant pr- esses, and by the inclusion of new important mechanisms and effects that come along with the development of new injection systems and have not been cons- ered so far. In this book the most widely used mathematical models for the simulation of spray and mixture formation in 3D CFD calculations are described and discussed. In order to give the reader an introduction into the complex processes, the book starts with a description of the fundamental mechanisms and categories of fuel - jection, spray break-up, and mixture formation in internal combustion engines.

Author: Udo Gerke
Publisher: Cuvillier Verlag
ISBN: 3736924992
Category : Technology & Engineering
Languages : en
Pages : 232

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Book Description
The present work investigates the mixture formation and combustion process of a direct-injection (DI) hydrogen internal combustion engine by means of three-dimensional numerical simulation. The study specifies details on the validity of turbulence models, combustion models as well as aspects on the definition of hydrogen-air burning velocities with respect to hydrogen IC engine applications. Results of homogeneous, stratified and multi-injection engine operation covering premixed, partially premixed and non-premixed combustion of hydrogen are presented. Results of the numerical simulations are validated using data of experimental analysis from parallel works, employing a one-cylinder research engine and a research engine with optical access. As a fundamental contribution to combustion modelling of hydrogen IC engines, a new correlation for laminar burning velocities of hydrogen-air mixtures at engine-relevant conditions is derived from measurements of premixed outwards propagating flames conducted in a single-cylinder compression machine. Numerical results of the direct-injection mixture formation give a detailed understanding of the interrelation between injection timing and the degree of mixture homogenisation. A favourable agreement between the computed fuel concentration and results of Planar Laser Induced Fluorescence (PLIF) measurements is reported for various injection timings. Different two-equation turbulence models, a Shear Stress Transport (SST) model and a k-ε model based on Renormalisation Group (RNG) theory as well as a Reynolds Stress Model (RSM) are discussed. The impact of the models on the level of turbulent kinetic energy proves to be of major importance. State-of-the-art turbulent combustion models on the basis of turbulent flame speed closure (TFC) and on the basis of a flame surface density approach, the Extended Coherent Flame Model (ECFM), are examined. The models are adapted to hydrogen internal combustion engines and are interfaced to the established three-dimensional flow field solver ANSYS CFX within the framework of the international research project HyICE. Two different approaches are investigated as input for the laminar burning velocities of hydrogen. Firstly, flame speed data are computed with a kinetic mechanism. Secondly, an existing experimentally derived laminar flame speed correlation is extended to rich air/fuel equivalence ratios (λ 1) and is compared to measurements conducted within the present work. In general, the TFC-models show a satisfying agreement for DI operating points compared to experimental data, when mixing computations are conducted with the SST turbulence model. Also, port fuel injection (PFI) operating points demonstrate a good performance with these models, however, the constant model prefactor (multiplier for the closure of turbulent flame speed) has to be defined individually for PFI and DI computations. This effect might be caused by the dissimilar sources of turbulence for the two engine types (PFI and DI) which cannot be adequately predicted by the turbulence models. Combustion computations on the basis of mixture results obtained by the RNG-model generally underrate the level of turbulence intensity for stratified operation points, effecting too weak rates of heat release. The ECFM combustion model shows a satisfying predictability for the PFI case using a constant model prefactor. Computations of DI operating points with this model, however, require a readjustment of the prefactor for each operating point in order to match experimental results. Regarding turbulent combustion, the hydrogen laminar flame speed is recognised to be the crucial quantity for the employed modelling approaches. Since direct-injection hydrogen engines in the stratified case engender a wide range of equivalence ratios, fundamental data for the laminar flame speed has to be provided as a model input within the entire boundaries of ignition limits. A lack of experimental data of laminar flame speed at engine-relevant conditions (high pressure, high temperature) is noticed. In order to perform a detailed study on hydrogen burning velocities, a single-cylinder compression machine is selected to conduct flame speed measurements of hydrogen-air mixtures at ignition temperatures and pressures up to T = 700 K and p = 45 bar, considering air/fuel equivalence ratios between λ = 0.4 and 2.8. Flame front velocities are acquired by means of optical methods using OH-chemiluminescence and thermodynamic, multi-zone evaluation of pressure traces. In comparison to data of laminar flame speed derived from reaction mechanisms and flame speed correlations found in literature, the experimental results show increased burning velocities due to flame front wrinkling caused by hydrodynamic and thermo-diffusive instabilities. a href="http://ec.europa.eu/research/transport/news/article_5199_en.html" EU Transport Research