[가솔린엔진부문] 이온신호를 이용한 직접분사식 가솔린 엔진의 노킹 특성에 관한 연구

There are two type of injection mode in direct injection gasoline engines. One is homogeneous mode that is used in high load operation and the other is stratified mode that is used in part load operation. Flame propagation and knock characteristics in direct injection gasoline engine may differ from those of port injection type because the piston of direct injection gasoline engine has cavity for stratified mode. So the study of knock characteristics and flame propagation in direct injection engine are needed. In this experiment, knock occurrence angle, knock occurrence cycle, knock intensity and location of knock occurrence are studied. Knock occurrence cycle increases and knock occurrence angle is earlier when air-fuel mixture is richer and load is higher. Knock intensity is also higher when air-fuel mixture is richer and load is higher. Knock occurs in the front and rear sides in the cylinder where flame reaches at the last.