T型管内流动气体中爆轰绕射过程的数值模拟

基于带化学反应的二维Euler方程，对H₂、O₂、Ar体积比为2:1:1的混合气体系统在T型管内的爆轰绕射进行了数值模拟。用二阶附加半隐的Runge-Kutta法和五阶WENO格式分别离散欧拉方程的时间和空间导数项，采用9组分48步基元反应简化模型描述爆轰波在静止系统和流动系统中的传播过程，得到了温度、压力、典型组元H质量分数的分布及数值胞格结构。结果表明:在流动系统中，迎风面上波阵面为斜爆轰结构，静止系统两侧和顺风面上的波阵面为完全解耦的前导激波；在水平管中，波阵面与上下壁面经历一系列马赫碰撞后，最终形成正爆轰；在流动系统中，胞格结构明显向下游偏移；横向爆轰波的产生对爆轰波的再生起到了关键作用。

Numerical investigation on evolution of detonation diffraction in moving gas inside a T-shaped channel

Based on two-dimensional Euler equations associated with chemical reactions, gaseous detonation of 2H₂/O₂/Ar mixture propagating through a T-tube was investigated numerically.The second-order additive semi-implicit Runge-Kutta methods and the fifth-order weighted essentially non-oscillatory (WENO) scheme were used to discretize the time derivative term and the space derivative term, respectively.The nine-specie and 48-elementary-reaction model was applied to describe detonation chemical reaction processes.The distribution of pressure, temperature and H mass fraction as well as numerical cellular patterns were obtained.Results show that, in the flowing mixture, the wave surface has an oblique detonation structure on windward side, while the wave on downwind side has a structure of leading shock wave decoupled from the reaction zone which is the same as the structure of waves on both side in quiescent mixture.After undergoing a series mach reflection incident, waves eventually form detonation waves propagating to left and right.In the flowing system, the whole cellular structure takes shape markedly further downstream.The emergence of transverse detonation has a key role for detonation reinitiation.