甲烷催化燃烧NOx排放特性的数值模拟

采用详细表面反应机理与气相反应机理GRI 3.0对甲烷-空气混合气体在微型管道内的催化燃烧过程进行二维数值模拟，讨论了不同甲烷浓度对NO_x排放量的影响，并对不同孔径内的浓度场、温度场与流场进行了研究。模拟结果表明：甲烷浓度的提高增加了反应器的排烟温度和NO_x排放量；孔道内径通过影响气相反应速率和催化反应速率改变了孔道内的温度场和速度场，进而影响了NO_x的生成；孔径的减小使得反应器的单位面积放热量和NO_x排放量均降低。以上结果可为优化催化反应器设计、降低其NO_x排放量提供参考。

Numerical simulation study of the NOx emission characteristics of the catalytic combustion of methane

The catalytic combustion of methane and air mixtures in a micro-tube has been numerically simulated by using a detailed surface reaction and a gas phase reaction mechanism GRI3. 0. The effects of varying the methane concentration on NO_x emissions were investigated, and the flow, temperature and concentration fields of channels with different pore sizes were studied. The simulation results show that increasing concentrations of methane, ledd to higher flue gas temperatures and NO_x emissions from the reactor. The pore size affects both the gas phase reaction rate and the catalytic reaction rate, by changing the temperature field and velocity field in the channel, thereby affecting the formation of NO_x. Decreasing the pore size results in lower heat release values per square meter and lower NO_x emissions, which provides a useful reference for designing catalytic reactors and reducing NO_x emissions.