用于燃烧反应机理构建的极小反应网络方法——芳香烃燃烧

Combustion Mechanism Construction Based on Minimized Reaction Network:Combustion of Aromatic Hydrocarbon

基于极小反应网络(MRN)方法,在燃烧机理的化学分辨率(化学物种数)确定的条件下,构建了极小反应网络的苯、甲苯、乙苯和丙苯通用复杂燃烧反应机理,机理分别由22个物种和35个反应、 27个物种和42个反应、 32个物种和58个反应以及36个物种和68个反应组成.建模方法是在极小网络C3机理基础上增加5个物种和14个反应构建苯燃烧机理,增加7个物种和15个反应得到甲苯燃烧机理;在苯燃烧机理基础上增加4个物种和8个反应构建乙苯燃烧机理,增加3个物种和7个反应得到丙苯燃烧机理.各个机理均采用Arrhenius方程的双参数形式(A, E)描述反应的速率常数.通过点火延迟时间和层流火焰速度的动力学模拟与实验结果的对比,验证各个燃烧反应机理的可靠性和实用性.

Based on the minimized reaction network(MRN)method,the combustion reaction mechanisms of benzene,toluene,ethylbenzene and n-propylbenzene for the specified chemical resolution,which consider both the necessary chemical species in combustion and the feasibility of three-dimensional combustion dynamic simulations,have been developed in this work.The chemical resolution is simply defined as the number of species involved in the reaction mechanisms.The new features of MRN approach including the small size of the reaction mechanisms,two-parameter rate constants,and the reversibility for all the“elementary”steps.The reaction mechanisms consist of 22 species with 35 reactions,27 species with 42 reactions,32 species with 58 reactions and 36 species with 68 reactions,for benzene,toluene,ethylbenzene and n-propylbenzene,respectively.It is worth noting that on the basis of the C3 core mechanism,the combustion mechanism of benzene has been constructed by adding 5 species and 14 reactions,and that of toluene constructed by adding 7 species and 15 reactions.On the basis of benzene mechanism,the combustion mechanism of ethylbenzene has been constructed by adding 4 species and 8 reactions,that of n-propylbenzene constructed by adding 3 species and 7 reactions,respectively.The correctness and reliability of these combustion reaction mechanisms have been verified by comparing with the experimental results of ignition delay time and laminar flame velocity.