Improvement of combustion performance and emissions in a gasoline direct injection (GDI) engine by modulation of fuel volatility

Abstract In this paper, five real distillate gasoline fuels with different 50%v distillation temperatures marked as G#1, G#2, G#3, G#4 and G#5, respectively, were used to investigate the effect of fuel volatility on the performance and emissions of a gasoline direct injection (GDI) engine. The indicated thermal efficiency, regulated and unregulated gas emissions and particulate matter (PM) emissions were tested under different loads. The results show that the fuels with different volatility had significant influence on combustion and emissions. When fueled with G#1, G#2 and G#3, respectively, the indicated thermal efficiency increased obviously. The HC emissions and CO emissions decreased while NOx emissions increased with the increase of gasoline volatility. Improving fuel volatility can effectively inhibit PM emissions. The total number of PM for G#1 was at a low level, especially at 4 bar (