Observations of Inversed-delta Fuel Injection Rate Diesel Combustion

Abstract

The characteristics of diesel fuel spray are very important for diesel ignition and combustion process affecting significantly on engine performance and exhaust emissions. In this study, using the constant volume vessel, which can simulate the gas temperature and pressure at the time of the fuel injection in the direct injection diesel engine, and a high-speed video camera, the observations of diesel fuel spray and combustion process have been made. In the experiments, the injection system having a direct-acting piezo-actuator was used to get arbitrary injection rate profiles which cannot be realized with conventional injection system. This paper reports the effects of fuel injection rate on the diesel combustion. Especially, the study focused on the inversed-delta injection rate.