通过CFD计算解决GDI发动机缸内喷雾湿壁问题

The Study on Spray Wetting Cylinder Wall Phenomenon of GDI Engine through CFD Analysis

应用CFD仿真技术,对GDI发动机缸内的喷雾过程进行了数值模拟分析,找到了汽油湿壁的关键影响因素,通过修改喷嘴布置和喷孔布局,降低了缸壁和活塞顶部的残余油量,解决了GDI发动机的汽油湿壁问题。

GDI engine has a lot of advantages, but the cylinder wall wetting of side-injection GDI engine usually occurs if spray and airflow in-cylinder match is not good. It will cause some problems such as the coke, smoke belching, and oil dilution and so on. In this paper, the spray process in cylinder of GDI engine was simulated through CFD to find out the key influencing factors of cylinder wall wetting. After modifying layout of nozzle and distribution of spray orifice, residual oil on the piston head and cylinder wall was reduced largely, and the cylinder wall wetting issue of GDI engine was solved.