扫气对直喷增压汽油机性能影响的试验研究

Experimental study on the effect of scavenging on direct injection turbocharged gasoline engine

研究在中低转速大负荷区域,不同气门重叠角形成的扫气对直喷增压汽油机充气效率、燃烧及排放性能的影响,在中低转速大负荷增压器裕度较小的区域,利用扫气可以有效提高发动机的充气效率和动力性,扫气越强,动力性提升越大,同时还能降低缸内的燃烧温度,减小爆震和超级爆震的倾向,但容易造成催化中排温的升高以及THC排放的恶化,重叠角大小还是需要综合均衡进行选择。

Research on low speed and high load area, different valve overlap angle formed by scavenging of injection turbocharged gasoline engine charging efficiency, combustion and emission performance, in low speed and high load turbocharger smaller margin area, the use of scavenging can effectively improve the charging efficiency and the power of the engine, the stronger the scavenging, the greater the dynamic performance,scavenging also can reduce the combustion temperature in the cylinder, knock and preignition tendency, but it is easy to cause the increase of catalyst temperature and the deterioration of THC emission, the overlap angle needs to be balanced.