Petrol engine

Abstract: Fundamental operating principles early internal combustion engine development, characteristics of internal combusion engines, additional types of internal combustion engine, prospects for internal combustion engines, thermodynamic principles introduction and definitions of efficience, ideal air standard cycles, comparison between thermodynamic and mechanical cycles, additional performance parameters for internal combustion engines, fuel-air cycle, computer models, combustion and fuels combustion chemistry and fuel chemistry, combustion thermodynamics, dissociation, combustion in spark ignition engines, combustion in compression ignition engines, fuels and additives, engine emissions, combustion modelling, spark ignition engines combustion chambers, catalysts and emissions from spark ignition engines, mixture preparation, electronic control engines, compression ignition engines direct injection (DI) systems, indirect injection (IDI) systems, cold starting of compression ignition engines, fuel injection equipment, diesel engine emissions, induction and exhaust processes valve gear, flow characteristics of poppet valves, valve timing, unsteady compressible fluid flow, manifold, silencing, two stroke engines two stroke gas flow performance parameters, scavenging systems, scavenge modelling, experimental techniques for evaluating scavenge and results for port flow co-efficients, engine performance and technology, in-cylinder motion flow measurement techniques, turbulence, turbocharging radial flow and axial flow machines, turbocharging the compression ignition engine, turbocharging the spark ignition engine, engine modelling zero-dimensional modelling, application of modelling to a turbocharged medium speed diesel engine, mechanical design considerations the disposition and number of the cylinders, cylinder block and head materials, the piston and rings, the connecting-rod, crankshaft, camshaft and valves, lubrication and bearings, advanced design concepts, heat transfer in internal combustion engines engine cooling, liquid coolant systems, experimental facilities quasi-steady engine instrumentation, experimental accuracy, measurement of exhaust emissions, computer based combustion analysis, advanced test systems, case studies Jaguar V12 HE engine, Chrysler 2.2 litre spark ignition engine, Ford 2.5 litre DI diesel engine. Appendices: the use of SI units answers to numerical problems engine specifications stratified charge engines engine tuning.

Abstract: HCCI combustion has been drawing the considerable attention due to high efficiency and lower nitrogen oxide (NOx) and particulate matter (PM) emissions. However, there are still tough challenges in the successful operation of HCCI engines, such as controlling the combustion phasing, extending the operating range, and high unburned hydrocarbon and CO emissions. Massive research throughout the world has led to great progress in the control of HCCI combustion. The first thing paid attention to is that a great deal of fundamental theoretical research has been carried out. First, numerical simulation has become a good observation and a powerful tool to investigate HCCI and to develop control strategies for HCCI because of its greater flexibility and lower cost compared with engine experiments. Five types of models applied to HCCI engine modelling are discussed in the present paper. Second, HCCI can be applied to a variety of fuel types. Combustion phasing and operation range can be controlled by the modification of fuel characteristics. Third, it has been realized that advanced control strategies of fuel/air mixture are more important than simple homogeneous charge in the process of the controlling of HCCI combustion processes. The stratification strategy has the potential to extend the HCCI operation range to higher loads, and low temperature combustion (LTC) diluted by exhaust gas recirculation (EGR) has the potential to extend the operation range to high loads; even to full loads, for diesel engines. Fourth, optical diagnostics has been applied widely to reveal in-cylinder combustion processes. In addition, the key to diesel-fuelled HCCI combustion control is mixture preparation, while EGR is the main path to achieve gasoline-fuelled HCCI combustion. Specific strategies for diesel-fuelled, gasoline-fuelled and other alternative fuelled HCCI combustion are also discussed in the present paper.

Abstract: The development of four-stroke, spark-ignition engines that are designed to inject gasoline directly into the combustion chamber is an important worldwide initiative of the automotive industry. The thermodynamic potential of such engines for significantly enhanced fuel economy, transient response and cold-start hydrocarbon emission levels has led to a large number of research and development projects that have the goal of understanding, developing and optimizing gasoline direct-injection (GDI) combustion systems. The processes 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 injectors 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 are of significant importance to engine researchers and developers. These data 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 aftertreatment hardware are reviewed in depth, and areas of consensus on attaining European, Japanese and North American emission standards are compiled and discussed. 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. All current information in the literature is used as the basis for discussing the future development of automotive GDI engines.

Abstract: A temperature wall function was derived for variable-density turbulent flows that are commonly found in internal combustion engines. Thermodynamic variations of gas density and the increase of the turbulent Prandtl number in the boundary layer are included in the formulation. Multidimensional computations were made of a pancake-chamber gasoline engine and a heavy-duty diesel engine under firing conditions. Satisfactory agreement between the predicted and measured heat fluxes was obtained. It was found that gas compressibility affected engine heat transfer prediction significantly while the effects of unsteadiness and heat release due to combustion were insignificant for the cases considered.