稀燃条件下掺烧乙醇重整气对直喷汽油机燃烧及碳烟排放影响的仿真研究  

Simulation Study on the Impact of Ethanol-Doped Reformate Gas under Lean Combustion Conditions on Combustion and Soot Emissions in Direct Injection Gasoline Engines

作　　者：石秀勇[1] 王浩宇 段毅菲 钱伟伟 Shi Xiuyong;Wang Haoyu;Duan Yifei;Qian Weiwei(Tongji University,Shanghai 201804)

机构地区：[1]同济大学,上海201804

出　　处：《汽车技术》2024年第2期47-54,共8页Automobile Technology

基　　金：汽车安全与节能国家重点实验室开放基金课题(KFY2229)。

摘　　要：为解决直喷汽油机稀薄气体的燃烧及排放问题,采用掺烧乙醇重整气改善直喷汽油机的性能,并利用CONVERGE三维仿真技术从微观角度解释发动机的性能表现。结果表明,引入乙醇重整气可以改善缸内当量比分布,促进H基、OH基的生成,有助于燃烧的良好进行;随重整气掺混比的升高,HO_(2)和H_(2)O_(2)分布范围更广、浓度更高,在燃烧室内分层现象更加明显;随着重整气掺混比增加到20%,缸内碳烟的生成质量和数量密度峰值分别降低了90%和56.25%,直喷汽油机碳烟排放得到有效改善。To address combustion and emission issues in the lean combustion of gasoline direct injection(GDI)engine,ethanol-doped reformate gas was used to enhance the engine’s performance.The CONVERGE three-dimensional simulation technology was employed to explain the engine’s performance at a microscopic level.The results show that introducing ethanol-doped reformate gas can improve the distribution of equivalence ratio in the cylinder,promote the generation of H radicals and OH radicals,facilitating effective combustion.With an increase in the doping ratio of reforming gas,the distribution range and concentration of HO_(2) and H_(2)O_(2) become wider and higher,and the stratification phenomenon in the combustion chamber becomes more pronounced.As the doping ratio of reforming gas increases to 20%,the peak values of in-cylinder soot generation mass and number density are reduced by 90%and 56.25%,respectively,effectively improving the soot emissions of GDI engines.

关 键 词：稀薄燃烧 乙醇重整气 直喷发动机 燃烧 排放 三维仿真 

分 类 号：U473.14[机械工程—车辆工程]