直噴式と副室式ディゼルエンジンの燃焼特性比較

抄録

In order to reduce fuel consumption, smoke and NO_x emissions of a diesel engine, the combustion and cycle characteristics of direct injection (DI) and indirect injection (IDI) diesel engines were investigated from the viewpoint of mixture formation energy, degree of constant volume of heat release and heat loss. As a result, the following conclusions were obtained. (1) The larger the mixture formation energy, which consists of jet, fuel injection and swirl energy, the better the combustion. (2) The combustion of the IDI diesel engine with larger mixture formation energy is better than that of the DI engine. (3) The fuel consumption of the DI diesel engine with higher degree of constant volume of heat release and lower heat loss is lower than that of the IDI engine. This lower heat loss is due to the reduction of specific surface area and coefficient of gas heat transfer.