二维会聚波在气体内传播不稳定性的数值模拟

Numerical simulation of instability of two-dimensional convergent shock wave propagating in gas

利用CE/SE(conservation element and solution element)格式研究了柱面会聚波在气体中传播时间断面的不稳定问题和波阵面的演变问题,并利用level set函数追踪了驱动气体与低压气体间断面的发展过程。得到了间断面的Rayleigh-Taylor(R-T)和Richt myer-Meshkov(R-M)不稳定性发展成典型的"尖钉"和"气泡"结构的图像,初始正弦扰动下的会聚波产生"尖角"和"尖瓣"结构。结果表明,CE/SE格式在涉及会聚波的数值计算中是可行的。

The discontinuity instability and wave front evolution of a cylindrical convergent shock wave propagating in gas were simulated by the CE/SE scheme. The evolution of the interface between the high-pressure driving gas and the low-pressure driven gas was revealed by the level set method. Both the typical ＂spire＂ and ＂bubble＂ discontinuity patterns due to Rayleigh-Taylor （RT） and Richtmyer- Meshkov （RM） instability, and the ＂polygon＂ and ＂petal＂ patterns developed from the initial sine convergent shock wave were obtained. Results demonstrate that the CE/SE scheme is feasible in numerical simulation involving convergent shock wave propagation.