氢气-空气混合物中瞬态爆轰过程的二维数值模拟

 对高温火团引发的氢气-空气混合气的瞬态爆轰过程进行了二维数值模拟，考虑了H₂-O₂-N₂的详细化学反应动力学机理，该机理包含了19个基元反应和9种组分。采用分裂格式处理带化学反应的Euler方程，其中使用全耦合的TVD格式求解流场，使用基于Gear算法的微分方程解法器求解化学反应过程。计算结果表明：在H₂∶O₂∶N₂＝0.4∶0.4∶0.2（摩尔比）的混合气中，高温气团初始温度为T/T₀=5.3时可诱导爆轰，爆轰波以2 300 m/s的速度传播，同时爆轰波阵面在管壁会形成反射波。还对计算的爆轰波后组分的浓度和温度进行了讨论，为理解爆轰波后结构提供信息。

Two-Dimensional Simulation of Transient Detonation Process for H2-O2-N2 Mixture

By solving the two-dimensional Euler equations coupled with the chemistry, a numerical simulation of transient detonation process induced by flame for H₂-O₂-N₂ mixture was performed, and a detailed chemical mechanism for H₂-O₂-N₂ system, which included 19 element reactions and 9 species, was involved. A splitting operator method was used to treat separately the hydrodynamical process and chemical process in the detonation simulation. The TVD scheme was used to capture the detonation wave and the Gear algorithm was used to solve the chemical reaction. The calculated results show that combustion rate of flame can be accelerated and lead to the occurrence of detonation when the initial mole fraction ratio of the mixture is H₂∶O₂∶N₂=0.4∶0.4∶0.2 and the initial nondimensional temperature is T/T₀=5.3, the detonation wave can be propagated steadily with the detonation velocity of 2 300 m/s. The reflection of the detonation wave can be observed. In addition, the variations of species concentrations and temperature behind the detonation wave were also discussed in order to understand the inherent structure behind the detonation wave.