【摘要】 本文通过激波管光测模型实验和数值计算两种手段,针对一平面激波S经下降台阶后与地面相互作用而产生的从规则反射RR到马赫反射MR转换的临界点L_k及激波入射角ω_i、反射角ω_r随距离L变化规律等问题进行了分析和研究。文中考虑了不同的入射激波马赫数M_i以及两种不同台阶高度的影响,并将光测模型实验和数值计算的结果同现有的理论结果做了比较。更多还原

【Abstract】 As a plane shock wave with shock mach number Mi propagates down a backward step of height H (fig 1) a part of the shock front turns to be curvilinear It reflects from the horizontal part behind step.This unsteady regular reflection eventually becomes Mach reflection.We present here the results of shock tube experiment (Mi≤2.20) and numerical simulation of this phenomena, say the transition from regular reflection (RR) to Mach reflection (MR) .The dependence of the position of transition LK, and critical angle of transition ωck on strength of the impinging plane shock Mi and height of step H are analysed.Our experimental and numerical results are compared with the theoretical criterion of transition of Iton & Itaya.It should be mentioned that the numerical method of FLIC type with triangular mesh developed in is successful.更多还原