Analysis the ECFM-3Z combustion model for simulating the combustion process and emission characteristics in a HSDI diesel engine

Abstract

An advanced CFD simulation has been performed to analyze the ECFM-3Z (Extended Coherent Flame Model-3Z) combustion model for simulating the combustion process and emission characteristics in a high speed direct injection (HSDI) diesel engine. A four cylinders, HSDI diesel engine based on a Ford production engine with a 2nd generation Delphi common rail fuel injection system has been modeled in this research. 3D CFD simulation was carried out from intake valve closing (IVC) to exhaust valve opening (EVO). A good agreement of calculated and measured in-cylinder pressure trace as well as pollutant formation trends could be observed for all investigated operating points. Based on the confidence gained from validation, the study is extended to evaluate the effect of fuel injection timing on engine performance and emissions. For this purpose, a comprehensive study of the effect of injection timing with respect to performance and emissions has been considered. Three main injection timing, (1) 2.65 BTDC, (2) 0.65 BTDC and (3) 1.35 ATDC, all with 30 crank angle pilot separations has been used to investigate the effect of the injection timing. The results show that the current methodology can be applied as a beneficial tool for analyzing the parameters of the diesel combustion under HSDI operating condition.