空气污染各组分对甲烷超声速燃烧性能的影响  

Effects of Species in Vitiation Air on Methane-Fueled Supersonic Combustion

作　　者：侯凌云[1] 杨缙[1] 马雪松[2] 刘巍[2] 

机构地区：[1]清华大学航天航空学院,北京100084 [2]北京动力机械研究所,北京100074

出　　处：《物理化学学报》2010年第12期3150-3156,共7页Acta Physico-Chimica Sinica

基　　金：国家自然科学基金(50306011)资助项目~~

摘　　要：在与甲烷详细化学反应机理对比验证基础上,采用18组分24步简化反应机理模拟甲烷超声速燃烧过程,从化学动力学和热力学角度用数值方法研究了乙醇燃烧加热空气中的七种主要污染组分(H2O,CO2,O,OH,CO,H,H2)对甲烷超声速燃烧性能的影响.分析结果表明:在一定条件下,进口空气中污染组分H2O的增加造成平均比热容增加,总温降低,并作为第三体抑制甲烷的燃烧过程,使超燃室的性能下降;CO2因大分子量特性使燃气平均分子量增大,降低超燃室做功能力,H2O和CO2两组分对甲烷超燃性能都起消极作用;污染组分自由基H、O、OH和燃烧中间产物CO、H2使燃烧室燃烧效率上升,对甲烷超燃性能起积极作用.Based on a detailed chemical reaction mechanism, a reduced reaction mechanism with 18 species and 24 steps was used to simulate the supersonic combustion of methane. Heated air calculations showed that seven main vitiated species, i.e., H2O, CO2, O, OH, CO, H, and H2, were present in ethanol- fueled heated air. We analyzed the effects of these species on methane-fueled supersonic combustion using chemical kinetics and thermodynamics. H2O inhibits the combustion process, decreases the combustion efficiency, and decreases the specific thrust. The relatively large molecular weight of CO2 contributes to an increase in the mean molecular weight of the fuel gas, which is a negative factor in the mechanism of specific thrust. Free radicals O, OH, H can effectively promote the combustion process and thus increase the combustion efficiency. Intermediate products CO and H2 increase the combustion efficiency, and this is a function of the additional fuel.

关 键 词：超声速燃烧 化学反应机理 污染空气 组分 

分 类 号：O643.32[理学—物理化学]