摘要
In order to explore the particle number (PN) emission characteristics of direct injection gasoline engine after cold start, the cluster operation points of worldwide harmonized light vehicles test cycle (WLTC) for direct injection gasoline engine were selected. The effects of fuel injection pressure and injection advance angle on PN emission were studied on engine test bench. And the PN emission of WLTC was compared based on the results of PN test bench optimization. The results show that the PN emission is relatively low when the injection advance angle is in the range of 240°~280° crank angle. And when the injection pressure is increased, the PN emission can be reduced by about 40%~70%. PN in the first phase of the direct injection vehicle decreased by about 40%, and the complete test cycle PN emissions decreased by about 30%. It can be concluded that the PN emission can be greatly reduced by selecting reasonable injection advance angles and increasing injection pressure under low load condition after vehicle cold start. ? 2022 Chinese Society for Internal Combustion Engines.
- 单位