喷射策略对乙醇汽油发动机颗粒物排放的影响  

Effect of Injection Strategy on Particulate Emission in an Ethanol-Gasoline Engine

作　　者：李庆宇 付建勤 刘敬平[1,2] 刘琦 沈瑶瑞[1] Li Qingyu;Fu Jianqin;Liu Jingping;Liu Qi;Shen Yaorui(Research Center for Advanced Powertrain Technology,Hunan University,Changsha 410082,China;Chongqing Research Institute of Hunan University,Chongqing 401120,China)

机构地区：[1]湖南大学先进动力总成技术研究中心,湖南长沙410082 [2]湖南大学重庆研究院,重庆401120

出　　处：《内燃机学报》2023年第5期450-457,共8页Transactions of Csice

基　　金：国家重点研发计划资助项目(2020YFB1506003);国家自然科学基金资助项目(51776061).

摘　　要：开展了多种燃油喷射策略对乙醇汽油发动机颗粒物排放影响的试验.结果表明:与单次喷射和2次喷射相比,3次喷射的颗粒物数量(PN)降低近50%,尤其是核态颗粒物降低更多.就降低颗粒物(PM)质量而言,采用多次喷射比增加乙醇比例的效果更明显.燃用3种乙醇体积分数为0(E0)、30%(E30)和85%(E85)的燃料下,总颗粒物排放随着乙醇比例增加而下降.对比两种瞬态工况发现,在绝大多数工况下3次喷射和5次喷射都比单次喷射的颗粒物浓度低.尤其是冷启动和大负荷工况下,多次喷射最多可将颗粒物浓度降低80%.随着乙醇体积分数增加,颗粒物粒径分布在绝大多数尺寸上都有明显下降,并通过降低爆震趋势可有效避免发动机性能下降和排放恶劣的现象.乙醇混合燃料结合多次喷射策略,在几乎不降低发动机动力性能的同时显著改善了颗粒物排放.The effects of various fuel injection strategies on particulate emission were experimentally studied on an ethanol-gasoline engine.The results show that compared with single injection and double injection,the particulate number(PN)of triple injection is reduced by nearly 50%,especially the nuclear PN.In terms of reducing particulate matter(PM),the effect of multiple injection is more obvious than increasing the proportion of ethanol.Among E0,E30 and E85 fuels,the total PN decreases with the increase of ethanol proportion.As for transient conditions,it was found that under most conditions,the particle concentrations of triple injection and quintuple injection are lower than those of single injection.Especially,under cold start and heavy load conditions,multiple injection reduces the particle concentration by up to 80%.With the increase of ethanol volume fraction,the particle size distribution decreases significantly in most sizes,and the engine performance degradation and poor emissions are effectively avoided by reducing the knock phenomenon.It is indicated that ethanol blended fuel combined with multiple injection strategy can significantly improve particulate emissions without reducing engine performance.

关 键 词：汽油机 乙醇 喷射策略 颗粒物 排放 

分 类 号：TK411.3[动力工程及工程热物理—动力机械及工程]