직접 분사식 가솔린 엔진의 분사시기에 따른 희박 연소 특성에 관한 연구

Abstract

Recently, the important issues of gasoline engine are fuel consumption and emission. So, many researchers are studying these problems. One approach to favorably these issues is to achieve homogeneous charge combustion and stratified charge combustion with various injection timing. The combustion and emission characteristics of DISI engine according to injection strategy were examined. The effect of injection timing on lean limit A/F were investigated using DISI single cylinder, and compared with the PFI engine’s characteristics. The results show the engine operation region of DISI engine is larger than PFI type engine. Especially, late injection extended the operation region more than early injection in DISI engine. However the emission of NOx was slightly increases than early injection case.