Highly boosted spark ignition engines must confront violent forms of pre-ignition limiting the maximal low-end torque. French research institute IFP presents here an innovative tool allowing a better understanding of this phenomenon and a structured reasoning considering all potential causes of this phenomenon. Advanced statistical analyses of the combustion process and direct visualisations in...

We analyze the experimental time series of internal pressure in a four cylinder spark ignition engine. In our experiment, performed for different spark advance angles, apart from the usual cyclic changes of engine pressure we observed additional oscillations. These oscillations are with longer time scales ranging from one to several hundred engine cycles depending on engine working conditions. ...

the intension in this work is to investigate the effect of different bending manifold pipes on engine performance for different engine speed. Power, Torque, and BSFC were calculated and presented to show the effect of varying bending pipes angles on them for all cases considered. A special program used to carry out the calculations. A simulation model for 4-cylinders spark ignition engine with ...

Fundamental studies on laser ignition have been performed by the US Department of Energy under ARES (Advanced Reciprocating Engines Systems) and by the California Energy Commission under ARICE (Advanced Reciprocating Internal Combustion Engine). These and other works have reported considerable increases in fuel efficiencies along with substantial reductions in green-house gas emissions when emp...

microhole electrical discharge machining (EDM) system with daptive fuzzy logic control and precision piezoelectric stage is eveloped in this study. A high-speed EDM monitoring system is mplemented to measure the gap voltage, current, and ignition elay time, which are used to derive three input parameters—the verage gap voltage, deviation in spark ratio, and change in the eviation in spark ratio...

The paper describes correlation between combustion knock intensity and combustion rate calculated as the heat release rate from combustion pressure traces of a hydrogen fuelled spark ignited engine. Unlike a gasoline spark ignited (SI) engine, the hydrogen fuelled engine can easily generate knock during combustion at working conditions similar to a gasoline engine. However, the hydrogen knock d...

A correct prediction of the ignition process represents a fundamental pre-requisite for a successful CFD simulation of combustion SI engines. Ignition involves many scales, physical and chemical phenomena that need to be described in detail. Within this context, the authors developed a Lagrangian model that can be used to predict the first stages of the combustion process in SI engines, when th...

Recent developments on highly downsized spark ignition engines have been focused on knocking behaviour improvement and the most advanced technologies combination can face up to 2.5 MPa IMEP while maintaining acceptable fuel consumption. Unfortunately, knocking is not the only limit that strongly downsized engines have to confront. The improvement of low-end torque is limited by another abnormal...

Temperature is one of the effective parameters in erosion of spark plug electrodes. In this research, temperature of spark plug was measured in engine's different operation conditions with two types of fuels: compressed natural gas and gasoline. Test results showed that, temperature of center electrode is lower than ground electrode and maximum difference between them is 110ºC that occurs at...

The spark energy transferred under the highly stratified conditions during late injection in a spray-guided spark-ignition direct-injection (SG-SIDI) engine is not well characterized. The impact of high pressures, temperatures, velocities, and variations in local fuel concentration along with temporal and/or spatial variations on spark performance must be better characterized. Previous spark ig...