Abstract
Vehicle engine is often used under acceleration condition. The fuel injection and combustion processes under acceleration condition are not the same as under steady condition. The fuel injection and combustion processes of a diesel engine during acceleration condition are investigated by measurement and simulation. The cyclic changes of fuel injection timing, fuel delivery per cycle per cylinder and injection rate curve are analyzed by fuel injection process simulation based on the measured engine transient speed and injection pressure. The cyclic changes of combustion characteristics, such as mean indicated pressure, heat release rate curve etc., are also analyzed.