Simulation study on the influence of fuel injection strategy on the soot emission of dual-injection engine

Abstract

A 2.0T gasoline engine was modified to a dual-injection engine. Numerical simulation method is used to study the influence of fuel type and fuel injection strategy on the in-cylinder mixture formation process, combustion process and soot emission of dual-injection gasoline engine. The simulation results show that an appropriate increase in the intake port fuel injection ratio can improve the uniformity of the air-fuel mixture. Increasing the fuel injection ratio in the intake port of the dual-injection system, the proportion of fuel directly injected into the cylinder decreases and the oil film distribution in the cylinder is reduced. Among the three injection schemes, the flame front of the D85 injection scheme reaches the cylinder wall earliest, and the flame spreads faster; the soot mass fraction generation decreases with the decrease of the GDI injection ratio. In particular, the amount of soot generated under the D65GDI injection ratio is significantly reduced.

Keywords

• gasoline engine
• numerical simulation
• dual injection
• soot emission