正十四烷在柴油机条件下芳香烃的形成及演化  

Polycyclic aromatic hydrocarbon formation during n-tetradecane combustion in diesel engines

作　　者：鞠洪玲[1] 成晓北[1] 

机构地区：[1]华中科技大学能源与动力工程学院,湖北武汉430074

出　　处：《华中科技大学学报（自然科学版）》2011年第9期112-116,共5页Journal of Huazhong University of Science and Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(50976039);清华大学汽车安全与节能国家重点实验室开放基金资助项目(KF10112)

摘　　要：以单缸直喷柴油机为研究背景,考虑了正十四烷(C14H30)燃料的详细化学反应机理,设计了化学成分的焓值计算程序,对缸内燃烧过程进行三维数值模拟计算,研究了诱发碳烟颗粒先导物生成的单环及多环芳香烃(PAHs)的形成,应用Belardini碳烟模型讨论了缸内碳烟颗粒的形成和演变过程,分析了PAHs对碳烟生成的影响.结果表明:缸内压力变化趋势的计算结果与实验模拟结果基本符合;芳香烃及PAHs的质量在急燃期急剧升高,而后迅速下降,并在燃烧后期达到一个稳定值;苯、苯乙炔、奈、菲的排放量较大,所采用的详细化学反应机理可以较好地反映复杂燃烧情况下多环芳香烃PAHs类中间物质、自由基等的生成机理.Three-dimensional numerical simulation in cylinder combustion was carried out based on a single cylinder direct inject diesel engine, while the detail chemical reaction mechanism of n-tetradecane was considered, and the enthalpy calculate subroutine of chemical species was built. The forma- tion and evolution mechanisms of aromatic （benzene） and polycyclic aromatic hydrocarbon, which were the precursor of soot particle, were calculated. Soot particle mass in cylinder combustion was calculated by Belardini soot model. The effect PAHs on soot formation was analyzed. The results show that numerical simulation of pressure through this computational model is in good agreement with the experimental results. Aromatic and polycyclic aromatic rapidly go up in the start of combus- tion, and then go down, and reach to a stable value in the end of combustion. Emissions of benzene, phenylacetylene, acenaphthene and phenanthrene are bigger than that of the others. Detailed chemical reaction mechanisms used can better reflect formation mechanisms free radical of PAHs in the condi- tion of complex combustion.

关 键 词：柴油机 碳烟 多环芳香烃(PAHs) 化学反应机理 正十四烷 

分 类 号：TK42[动力工程及工程热物理—动力机械及工程]