직분식 가솔린 엔진용 선회 분사기의 연료 온도에 따른 노즐 내부 및 주변의 액막 유동 변화

Abstract

The fuel temperature before injection can be affected by cylinder head and in-cylinder gas temperatures. This change in fuel temperature causes a significant change in spray characteristics from swirl injector. This investigation is aimed at identifying the variation in flow conditions inside and near the nozzle of a swirl injector as a result of increasing fuel temperature. The liquid film inside a transparent nozzle attached to the main nozzle of the injector was visualized and its thickness variation at different fuel temperatures was analyzed. The liquid film profile and nozzle spray angle were also investigated very close to the nozzle exit. Gasoline and isooctane which have different boiling points were used to identify the effects of evaporation. Results showed that significant variations in liquid film and flow profile exist as the fuel temperature increases when using gasoline compared to isooctane.