【摘要】 通过耦合计算流体力学软件FLUENT和化学反应动力学软件CHEMKIN,并运用空间气相和表面催化详细化学反应机理,对氢气和空气的预混合气体在微型管道内的催化燃烧过程进行了数值模拟,讨论了不同反应模型的燃烧特性以及表面催化反应对空间气相反应的影响。计算结果表明:OH浓度的高低可用来判断微型管道内是否发生表面催化反应。由于壁面的催化作用,空间气相反应发生的难度增加,即表面催化反应对空间气相反应有抑制作用;表面催化反应对空间气相反应的影响能被分成三种类型。计算结果为在微型动力系统中实现催化燃烧以及扩展燃烧极限提供了理论依据。更多还原

【Abstract】 Catalytic combustion of hydrogen/air mixture inside micro-tube was numerically investigated with detailed the gas phase and the surface catalytic chemical reaction mechanisms by using the commercial fluid dynamics code FLUENT coupled with the chemical reaction dynamics subroutine CHEMKIN. Combustion characteristics for different reaction models and the effect of the surface catalytic reaction on the gas phase reaction were discussed. The Computational results indicate that the difference of OH concentration can be used to identify whether the surface catalytic reaction occurs inside the micro-tube. The gas phase reaction will be inhibited by the catalytic wall. The surface catalytic combustion restrains the gas phase combustion. The effect of the surface catalytic reaction on the gas phase reaction can be divided to three types. Some theoretical evidences are provided for the application of catalytic combustion to micro-electromechanical system (MEMS) and the extension of the combustion limits.更多还原