Experimental Research of 500 bar Ultra-high-pressure Fuel Injection System for Gasoline Direct Injection Engine

The characteristics of 500 bar ultra-high-pressure fuel injection system was studied on a 1.5 L gasoline direct injection (GDI) engine, the comparison of gaseous and particulate emissions and fuel consumption under cooled and hot engine conditions was analyzed between 350 bar and 500 bar of injection pressure, including part load, full load, and mini map points that have been extracted from world light-duty test cycle (WLTC). The results show that, the benefit of particulate decease from 500 bar will be achieved at different conditions, which could reach roughly up to 50% at part load while 30% for average at full load. Moreover, both of the nucleate and accumulative particulates show obvious improvement at all the sizes range, which will provide effective solution for meeting the challenge of particulate limit with smaller size from more stringent legislations. On the other hand, the ultra-high-pressure fuel injection almost would not produce negative effect on fuel consumption and gas emission under most conditions.