烷烃催化燃烧的数值模拟

对甲烷、乙烷在表面涂有催化剂的微元管内的催化燃烧进行了模拟．讨论了微元管入口速度、直径、入口温度以及混合气中甲烷与氧气的摩尔比对甲烷催化燃烧特性的影响；分析了单体式蜂窝块中甲烷的着火温度及单个微元管中气体温度、主要气相组分与表面组分的质量分数的变化趋势．分析了不同混合气及不同混合气摩尔比下乙烷的催化燃烧特性，数值模拟结果与实验结果基本一致；提出了碳原子数为3或大于3的烷烃催化反应简化机理的建立方法．为在内燃机中实现催化燃烧以降低氮氧化合物、未燃碳氢化合物及一氧化碳的排放，及扩展燃烧极限提供了理论依据．

Numerical Simulation of Catalytic Combustion of Alkane

Numerical simulations of catalytic combustion of methane ,ethane in the micro-channel whose surface are coated with catalyst are conducted. The influences of the gas intake speed, channel diameter, intake temperature, and the ratio of mole methane/oxygen on catalytic combustion characteristics are discussed. The ignition temperature of methane in monolith and the variational trend of the gas temperature, the mass fractions of the main gas species, and surface species in single micro-channel are analyzed. The catalytic combustion characteristics of ethane at different gas-mixtures and various mole ratios of gas-mixture were presented, and comparisons between numerical simulation and experiments show a basic agreement. The method for simplifying the reaction methanism of catalytic combustion of alkane whose carbon atom is three or more than three is suggested. Some theoretical evidences are provided for the extension of the combustion limits and the application of catalytic combustion to internal combustion engine to decrease the emissions of NOx, UHC and CO.