High Pressure and Split Injection Strategies for Fuel Efficiency and Emissions in DI Diesel Engine

摘要

The focus on fuel efficiency, performance, and the regulatory requirements of emissions have brought the attentions on injection strategies for improvement of in-cylinder mixture preparation and elimination of the sources of combustion emissions, in particular the in-cylinder particulate formation. In this paper, with the focus on better fuel efficiency and reduction of emissions, high-pressure and split injection strategies were investigated in a single cylinder DI diesel engine. It provides results of a study of the influence of fuel pressure increase between 30 to 180 MPa, in conjunction with the main injection events split in two or three, on the combustion characteristics, specifically the particulate and gaseous emissions and the fuel economy. The experimental data shows the marked effect of fuel pressure increase on reduction of the particulate emissions. It also illustrates improvement of fuel consumption of the split main injection events, remarkable at around 100 MPa of fuel pressure. The data highlights the complex relation of the fuel pressure and split main injection events on gaseous emissions, which must be taken into consideration for DI diesel combustion system optimization.