活塞温度对汽油机颗粒物排放的影响

朱小平，陈广

宁波吉利罗佑发动机零部件有限公司，浙江 宁波  315336

摘要：为降低直喷汽油发动机的颗粒物排放，分析颗粒物产生原因，改进活塞冷却喷嘴结构，设计活塞冷却喷嘴控制策略，研究冷起动阶段活塞温度对发动机颗粒物排放的影响。结果表明：根据机油温度控制活塞冷却喷嘴的开启，在冷起动阶段减少活塞与机油的换热，使活塞温度快速提升，缩短暖机时间，使混合气在活塞温度较高时燃烧，大幅度降低颗粒物排放。

关键词：直喷汽油发动机；活塞冷却喷嘴；冷起动；粒子数量

Effect of piston temperature on particle emission of gasoline engine

ZHU Xiaoping, CHEN Guang

Ningbo Geely Royal Engine Components Co., Ltd., Ningbo 315336, China

Abstract：In order to reduce the particle emission level of gasoline direct injection engine,the cause of particulate matter is analyzed, the structure of piston cooling jet is optimized, and a control strategy for the piston cooling jet is designed.The effects of piston temperature during cold start phase on particle emission are studied. The results show that controlling the piston cooling jet open and close timing, reducing the heat exchange between piston and oil during cold start phase, can help the piston temperature rise more quickly and shorten engine warm up duration. Keeping the fuel and air mixture burn on higher piston temperature, the particle number can be reduced.

Keywords:gasoline direct injection engine;piston cooling jet;cold start;particle number