正庚烷甲苯混合物燃烧简化机理分析  

Reduced Combustion Mechanism of n-Heptane/Toluene Mixtures

作　　者：雒婧[1,2] 尧命发[1] 

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]河北工业大学能源与环境工程学院,天津300401

出　　处：《燃烧科学与技术》2012年第4期367-374,共8页Journal of Combustion Science and Technology

基　　金：国家自然科学基金资助项目(50976078);国家杰出青年基金资助项目(51125026)

摘　　要：提出了一个新的包括多环芳香烃(PAH)生成的正庚烷/甲苯混合物燃烧化学动力学简化机理.该机理包括64种物质,120个反应,与激波管内滞燃期实验结果吻合较好.在不同进气氧体积分数下,使用该机理对柴油机缸内燃烧过程进行了计算,其结果与缸内的实验结果吻合良好.通过机理的敏感性分析发现,PAH的重要前驱物乙炔主要是由甲苯反应路径中的C6H5及C6H4O2生成,说明在正庚烷中加入甲苯会对模拟柴油的燃烧特别是碳烟的生成有很大的影响;过氧化氢自由基HO2和羟自由基OH在甲苯、正庚烷的分解反应及小分子烃的裂解和氧化反应中都起着非常重要的作用.A new reduced kinetic mechanism of n-heptane/toluene including polycyclic aromatic hydrocarbon （PAH） formation was presented. The new mechanism, which includes 64 species and 120 reactions, matches the shock-tube test data well. Then, the diesel combustion processes were simulated at different inlet oxygen concentrations by the mechanism, and the results agree well with the experiments. Through the sensitivity analysis, it was found that acetylene, an important precursor of PAH, is mainly generated by C6H5 and C6H402, which are from the reaction of toluene, indicating that toluene has a great impact on simulating diesel combustion process and soot emission. HO2 and OH radicals play very important roles in both the decomposition of toluene and n-heptane, and the pyrolysis and oxidation of small-molecule hydrocarbon.

关 键 词：正庚烷 甲苯 燃烧 简化机理 

分 类 号：TK421.4[动力工程及工程热物理—动力机械及工程]