为了解决GDI发动机低速情况下湿壁的问题,针对某GDI发动机的低转速工况,优化其喷油特性,从喷油策略上对比了单次喷射和二次喷射的雾化结果以及最终得到的缸压曲线。在一定的两次喷油比例上,比较了喷油时刻对湿壁量以及最后火花塞附近当量比的影响,同时还计算了壁面油膜的蒸发量和最终壁面残余的油膜质量,这些将是对HC排放重要的判定依据。 In order to solve the problem of wet wall of GDI engine at low speed, aiming at the low speed condition of a GDI engine, the injection characteristics of the GDI engine are optimized. The atomization results of single injection and secondary injection are compared with those of the final injection Cylinder pressure curve. In a certain proportion of the two fuel injection, compared the injection time on the wet wall and the final spark plug near the equivalent ratio of the impact, while also calculating the evaporation of the wall film and the final wall residual oil film quality, these will be HC Important basis for determining emissions.