内燃机工程2018，Vol.39Issue(2)：66-73,8.DOI:10.13949/j.cnki.nrjgc.2018.02.011
后喷策略对柴油机瞬变过程高负荷工况性能的影响
Influence of Post Injection Strategy on Diesel Engine Performance at Heavy Load and under Transient Conditions
摘要
Abstract
In order to solve the combustion deterioration and emissions increase of heavy duty diesel engines under transient conditions,the study of the influence of the fuel post injection on transient performance was carried out on a heavy duty vehicle diesel engine with 8.6 L displacement,and the influence and its mechanism of the fuel post injection on combustion process,air flow and soot emissions were analyzed by simulation.In order to better illustrate the mixing process of mixture in the cylinder,the concept of oxygen driven energy was introduced thereafter.Results show that in the main injection stage,the oxygen driven energy plays a leading role in the formation of in-cylinder mixture,With the increase of the amount of fuel post injection the in-cylinder disturbance increases,resulting in an increase in the ratio of lean mixture which makes the second and third peak of heat release rate enhance and the combustion phase advance,but the amount of fuel post injection has little influence on the NOxemissions.In view of the combined consideration of thermal efficiency and soot emissions,the use of an interval of 4°crank angle between the main and post injections and amount of 25% post injection has a best emission effect at 90% load and under transient conditions.关键词
柴油机/数值模拟/瞬变性能/后喷参数/高负荷Key words
diesel engine/numerical simulation/transient performance/post injection parameter/heavy load分类
能源科技引用本文复制引用
刘忠长,冯荣梅,田径,马志双,金文华..后喷策略对柴油机瞬变过程高负荷工况性能的影响[J].内燃机工程,2018,39(2):66-73,8.基金项目
"九七三"国家重点基础研究发展规划项目(2013CB228402)973 National key Basic Research Development Program of China(2013CB228402) （2013CB228402）
