柴油机高密度-低温燃烧的数值模拟  

Numerical Simulation on High Density-Low Temperature Combustion in Diesel Engines

作　　者：苏万华[1] 鹿盈盈[1] 于文斌[1] 黄豪中[1] 韩志强[1] 赵霏阳[1] 裴毅强[1] 孙田[1] 孙永亮 

机构地区：[1]天津大学内燃机燃烧学国家重点实验室,天津300072 [2]潍柴动力股份有限公司,潍坊261021

出　　处：《燃烧科学与技术》2010年第3期191-198,共8页Journal of Combustion Science and Technology

基　　金：国家重点基础研究发展计划(973)资助项目(2007CB210001);国家自然科学基金资助项目(50636040)

摘　　要：从柴油机燃烧过程控制的思想出发,解释了高密度-低温燃烧概念的内涵.数值模拟结果表明,高充量密度在提高热容方面与EGR具有相同的作用.因此,低温燃烧使用较低的EGR率时就能实现很低的NOx和碳烟排放;另外,高充量密度促进了燃空混合率,特别是促进了燃烧后期的混合速率,极大地缩短了燃烧持续期,提高了指示热效率,高密度-低温燃烧的这一特征对柴油机高负荷和全负荷下实现高效、低排放运行具有突出的优势.研究结果还显示,充量密度对燃烧过程参数的影响是多重的,不同于传统柴油机燃烧.A study of high density-low temperature combustion in diesel engines has been conducted by engine test and CFD simulation.It is found that the high charge density can play the same role in increasing heat capacity as ex-haust gas recirculation（EGR）does.Therefore,low temperature combustion can achieve very low NOx and soot emis-sions with less EGR（about 18%—19% oxygen concentration） which is extremely important at high and full loads.In addition,high charge density promotes fuel/air mixing rate,thus promoting buring rate especially in the later phase of engine combustion and shortens the combustion durationl,eading to higher thermal efficiency.The effects of charge density on combustion in diesel engines are found to be multi-fold and the combustion parameters are different from those of conventional diesel combustion.

关 键 词：柴油机 低温燃烧 高充量密度 废气再循环 可变气门定时 

分 类 号：TK421.2[动力工程及工程热物理—动力机械及工程]