单次脉冲爆轰发动机工作过程的数值模拟

Numerical simulation of the process on a pulse detonation engine

通过求解14组分和19个基元反应的CH4-O2-N2详细化学反应动力学机理的二维轴对称Navier-Stokes方程,对爆轰管内半球形高温火团引发的爆轰过程和爆轰波进入外流场后的全流场分布进行数值模拟。模拟结果显示了爆轰波在管内的成长、稳定传播、进入尾喷管后衰减为激波和进入外流场的全过程,以及爆轰管出口端附近区域的复杂涡与激波的相互作用。对轴线上的压力分布和封闭端的压力等进行了讨论,为脉冲爆轰发动机的开发研制提供参考信息。

By solving two-dimensional axisymmetric Navier-Stokes equations in conjunction with the chemistry, a numerical simulation of pulse detonation process induced by flame in the tube with CH4-O2-N2 mixture and the flow field outside was performed, and a detailed chemical mechanism of CH4-O2-N2 system, which included 14 species and 19 element reactions, was involved. The computational results demonstrate the process of the development, steady propagation, degenerating into a shock after the detonation wave went into the flow field outside and complex vortex/shock interactions in the vicinity of the thruster exit. The pressure distribution of axis and the head-end （thrust wall） thrust history were discussed to research and exploit a pulse detonation engine.