승용디젤엔진에서 연소실 형상 변화에 따른성능 및 배기 특성

Abstract

The main objective of this study is to investigate the effect of aspect ratio of combustion bowl. The aspect ratio is defined as the ratio of a torus diameter to a depth. In order to understand the effect of the aspect ratio on engine performance and emissions, four piston bowls with different aspect ratios were tested. The experiments were carried out on a single cylinder direct injection diesel engine equipped with a high pressure common-rail injection system. Engine power output, emissions and cylinder pressure were obtained and analyzed. Tests were performed at various injection timings with 7-hole injector under medium load and speed conditions. Also, different protrusions and injection angles of injectors were tested. Optimized aspect ratio of combustion bowl, injector prutrusion and injection angle was sought to reduce the particulate emission and to improve the power output.