正庚烷低压预混燃烧火焰中间产物生成特性分析  

Combustion Intermediate Radical Characteristics of N-Heptane in a Low-Pressure Premixed Laminar Flame

作　　者：秦先锋[1] 袁银男[2] 李仁春[1] 李立琳[1] 

机构地区：[1]江苏大学汽车与交通工程学院,江苏镇江212013 [2]南通大学机械工程学院,江苏南通226019

出　　处：《机械设计与制造》2014年第3期262-264,共3页Machinery Design & Manufacture

基　　金：国家自然科学基金(No.50776042);江苏省高校自然科学基金重点项目(No.08KJA470001)

摘　　要：采用数值模拟的方法研究正庚烷低压预混层流燃烧火焰,分析了正庚烷化学反应路径及燃烧产物,考察了OH,O,H自由基的摩尔分数变化,比较了火焰中同类烷烃、烯烃和炔烃摩尔分数,通过C2H4的敏感性分析探讨了燃烧火焰中烯烃生成和消耗路径.结果表明：随火焰高度的增加,H2O、CO和CO2摩尔分数增大,火焰高度1.3cm以后,CO的摩尔分数开始下降,对应的CO2摩尔分数迅速增加.OH,O,H自由基摩尔分数的最大量级为10-4～10-3,OH,O,H自由基摩尔分数的迅速增大反映燃烧中间产物的消耗反应较剧烈.正庚烷燃烧火焰烯烃生成较多,C2烯烃摩尔分数的峰值分别是同类烷烃和烯烃的32、85倍,C3烯烃的摩尔分数的峰值是同类炔烃72倍.A numerical study on low-pressure premixed N-heptane laminar flame was conducted.This work focused on both the chemical reaction path and the combustion intermediate.Therefore,mole fraction variation of OH,O,and H radicals were analyzed,and the resultants of similar olefirs,alkanes,and alkynes in the flame were compared.The numerical result showed that with the increase of flame height,H2O,CO and CO2 mole fraction increased,after the flame height 1.3cm,CO mole fraction began to decrease,correspondingly CO2 mole fraction increased rapidly,and CO was oxidized to CO2 The maximum magnitude of the mole fraction of OH,O,and H radicals were 104～10-3.The rapid increase reflected that the reaction of combustion intermediate consumption was severe.The comparison of resultants revealed that generation of olefins in low-pressure premixed N-heptane laminar flame were more than other resultants,which the peak of mole fraction of C2 Olefin are respectively 32 and 85 times more than similar alkanes and olefins,likewise,7.2 times much more than the same kinds of alkynes compared to C3 Olefin.

关 键 词：正庚烷 预混燃烧 中间产物 自由基 

分 类 号：TH16[机械工程—机械制造及自动化] TK401[动力工程及工程热物理—动力机械及工程]