摘要
针对2023年加严的真实驾驶排放(RDE)低温环境下颗粒物数量(PN)排放限值,旨在研究缸内直喷(GDI)汽油机的RDE冷机PN来源以及抑制策略。基于内窥镜光学诊断技术,试验研究了一台增压GDI汽油机的RDE冷机PN来源,并分析了多次喷射策略对冷机PN排放的影响。试验结果显示,汽油机冷机PN排放主要源于3个方面。其中,因活塞表面汽油湿壁现象所引起的扩散燃烧最多。采用GDI 4次喷射策略可显著降低由活塞表面汽油湿壁现象所引起的扩散燃烧,从而将冷机PN排放降低88%。因此,对于冷机较多的RDE测试循环、全球统一轻型车辆测试循环而言,多次喷射策略是降低冷机PN排放的关键技术。
In response to the stricter real driving emission(RDE)limits for particle number(PN)emissions under low-temperature conditions effective in 2023,this study aims to investigate the sources of RDE cold-start PN emissions in a gasoline direct injection(GDI)engine and explore suppression strategies.Based on endoscopic optical diagnostics,experimental research was conducted to identify the sources of RDE cold-start PN emissions in a turbocharged GDI engine,and the impact of multiple-injection strategies on cold-start PN emissions was analyzed.The experimental results indicate that cold-start PN emissions from the gasoline engine mainly originate from three sources.Among these,diffusion combustion caused by fuel wall-wetting on the piston surface contributes the most.The application of a GDI four-injection strategy significantly reduces diffusion combustion resulting from fuel wall-wetting on the piston surface,thereby lowering cold-start PN emissions by 88%.Therefore,for RDE test cycles and the worldwide harmonized light vehicles test cycle,which involve frequent cold-start conditions,the multiple-injection strategy serves as a key technology for reducing cold-start PN emissions.
作者
尹兆雷
YIN Zhaolei(Middle Platform Engineering Department,United Automotive Electronic Systems Co.,Ltd.,Shanghai 201206,China)
出处
《汽车零部件》
2025年第10期24-27,共4页
Automobile Parts
关键词
颗粒物数量
缸内直喷汽油机
多次喷射策略
RDE测试循环
冷机
particle number
gasoline direct injection engine
multiple-injection strategy
RDE test cycle
cold-start
