内燃机工程2024，Vol.45Issue(2)：8-17,10.DOI:10.13949/j.cnki.nrjgc.2024.02.002
基于射流点火和气道喷水技术的缸内直喷汽油机稀薄燃烧特性研究
Study on Lean Combustion Characteristics of Gasoline Direct Injection Engines with Jet Ignition and Intake Water Injection Technologies
李勇 1吴威龙 1李钰怀 1陈泓 1张宗澜 1杜家坤1
作者信息
- 1. 广州汽车集团股份有限公司 汽车工程研究院,广州 511434
- 折叠
摘要
Abstract
Based on a four-cylinder turbocharged gasoline engine,a pre-chamber and an intake water injection system were added.Experimental tests were conducted at the optimal fuel consumption conditions(2 500 r/min,brake mean effective pressure(BMEP)=0.8～1.2 MPa)to analyze the characteristics of the lean combustion of a gasoline engine,as well as the effects of jet ignition and intake water injection on lean combustion performance.The results show that lean combustion can increase the brake thermal efficiency(BTE)from 39.5%for stoichiometric combustion to around 42.5%.However,combustion stability and total hydrocarbon(THC)emissions deteriorate when the excess air ratio exceeds 1.4.By adopting jet ignition technology,the excess air ratio for stable combustion can be extended to above 1.7,and the BTE can increase to over 43%.The combustion duration can be reduced by a maximum of 37.6%,and the cycle of variation(COV)does not exceed 1.3%.Furthermore,with the addition of intake water injection,the knocking suppression effect is significant for loads with BMEP above 1.1 MPa.When the water injection pulse width reaches 4 ms,the knock-limited CA50 can be advanced to approximately 8° after top dead center,while achieving a maximum BTE of over 44%and COV within 3%.However,for loads with BMEP below 1.1 MPa,since knocking is not serious,water injection instead reduces the combustion rate and thermal efficiency,while worsening combustion stability and THC emissions.关键词
汽油机/稀薄燃烧/预燃室/射流点火/喷水Key words
gasoline engine/lean combustion/pre-chamber/jet ignition/water injection分类
能源科技引用本文复制引用
李勇,吴威龙,李钰怀,陈泓,张宗澜,杜家坤..基于射流点火和气道喷水技术的缸内直喷汽油机稀薄燃烧特性研究[J].内燃机工程,2024,45(2):8-17,10.
