二维双楔外形穿越激波流场特性及其数值分析

Computational analysis of the unsteady flow induced by a double-wedge shaped projectile overtaking shock waves

用数值方法求解非定常可压缩Navier Stokes方程 ,模拟了双楔外形物体超音速穿越与之同向运动激波以及逆向运动激波两种穿越激波的全过程 ,给出了穿越过程中流场与运动激波产生剧烈的干扰所形成的复杂波系结构 ,两种穿越情况的激波干扰都呈现双马赫反射的特征。在追击穿越中 ,楔形物体追上激波后所受阻力急剧的变小 ;而在碰撞穿越过程中 ,物体碰到激波后阻力急剧增加 。

Numerical simulations of the flow field around a double-wedge shaped projectile overtaking shocks are carried out by solving unsteady compressible Navier-Stokes equations. Two test cases, the pursuing overtaking and the colliding overtaking are considered, and discussed the complex structure of wave systems, which is induced by the interaction of the flow field and the moving shock wave. The double Mach reflection is observed in both cases. In the case of colliding overtaking, the drag, which is rapidly reduced in pursuing overtaking is greatly increases, after the projectile goes through the shock wave. The aerodynamic forces of the projectile show rapid variations.