NOx and soot emissions remain critical issues in diesel engines. One method to address these problems is to achieve homogeneous combustion at lower peak temperatures – the goal of research on controlled autoignition. In this paper n-heptane is used to represent a large hydrocarbon fuel and some of the effects of internal and external EGR, oxygen concentration, and engine speed on its combustion...

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 ...

In recent years, the industry has shifted toward down-sizing and turbo-charging spark ignition (SI) engines in an effort to increase fuel conversion efficiency. However, this has given rise to a destructive phenomenon known as sporadic pre-ignition (SPI). At low cranking speeds and high loads, engines have been observed to knock violently for brief and infrequent intervals. If allowed to contin...

We report on the design and output performances of a diode pumped, high-peak power Nd:YAG/Cr 4+ :YAG laser with four-beam output. The system posses the ability to chose independently the focus of each laser beam, being seen as a solution for a laser spark with multiple-point ignition. The laser ignition of a gasoline direct injected engine has several advantages in comparison with ignition by e...

This paper presents the effect of friction on the performance of spark ignition engine using gas mixture as working fluid. The results were compared to frictionless engine. Engine parameters that were studied include equivalence ratio, engine speed, break mean effective pressure (BMEP), and cycle thermal efficiency. It was found for the frictionless engine operating at 6000 rev min and stoichio...

Cooled exhaust gas recirculation is emerging as a promising technology to address the increasing demand for fuel economy without compromising performance in turbocharged spark injection engines. The objectives of this study are to quantify the increase in knock resistance and to decrease the enrichment and emission at high load. For this purpose four stroke turbo charged Spark Ignition engine (...

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...