中文摘要：

分析了滑移线延长线与楔面交点附近的流动特点，研究了准定常强激波反射中马赫杆的变形，建立了马赫杆突出变形消失的过渡准则，并用激波极曲线方法进行了求解。对马赫杆的变形过程进行了描述，研究了比热比、马赫数的变化对马赫杆突出变形消失条件的影响，并对突出变形消失区域与终点双马赫反射区域进行了比较。结果表明：马赫杆突出变形的消失是低比热比介质中出现的一种激波反射现象。马赫杆突出变形的消失，导致出现一种新的无射流、直马赫杆的双马赫反射结构。

英文摘要：

To investigate into the deformation of the Mach stem in a strong shock reflection, the flow field near the intersection point between slip line and wedge surface was theoretically analyzed, and a transition criterion for Math stem deformation to disappear was derived, which was solved with the shock polar method. Processes of Mach stem deformation were described, and effects of ratio of specific heats and Math number on conditions for Mach stem deformation to disappear, which were compared with those in presence of terminal double Mach reflections, were investigated. The results show that the disappearance of Mach stem deformation is a reflection phenomenon of shock waves in mediums with low ratios of specific heats. The disappearance of Mach stem protrusion leads to a new configuration of double Math reflection with a straight Mach stem and no wall jet.