Analysis of Shock Wave System with Composed Structure Induced by Near Field Collision between Supersonic Jet and Solid Wall

利用TVD法进行了数值计算，并对流动显示和壁面温度测量进行了实验分析，探讨了温度峰的产生机理。其次，我们尝试控制由表面条件引起的压力波。结论总结如下：(1)分离泡的存在使流动速度、驻点位置和数量发生复杂变化。(2)分离泡的产生改变了壁面压力分布，分离泡产生时出现局部压力峰值。压力峰值的位置取决于壁面的无量纲距离和压力比。(3)射流中马赫数盘的位置上移，直径扩大而非自由射流。马赫盘后的压力比自由射流的压力大。(4)壁面上的最高温度和压力在壁面与射流轴线交点附近产生，第二峰温度和压力由分离泡产生。这些峰值位置受到自激振荡的影响。(5)射流十字位置的时间平均压力随压力比的增大和板的位置的增大而减小。(6)在上下尾激波与斜壁面的相互作用点处观察到边界层曲率的变化，这是由于分离泡的产生。(7)斜面轴上的温度峰值是由边界层厚度的变化和激波与壁面相互作用产生的温度峰值共同产生的。(8)喷嘴轴向温度随表面粗糙度的增加而升高。

The numerical calculation using the TVD method and the experimental analysis of flow visualization and measurements of wall temperature are carried out, and discussed the generation mechanism of the temperature peak. Next, We try to control the pressure wave induced by surface conditions. The conclusions are summarized as follows.(1) The flow velocity and the position and numbers of stagnation point are complexly changes by the existence of the separation bubbles.(2) The pressure distribution on the wall changes by the separation bubble, and the locally pressure peak are occurred when the separation bubble is generated. The positions of pressure peak are dependent on the non-dimensional distance of wall and pressure ratio.(3) The position of the Mach disk in the jet moves to upper side and diameter is extend rather than free jet. The pressure behind the Mach disk is increment than the free jet.(4) The maximum temperature and pressure on the wall are generated near the cross point of wall and axis of the jet, and the secondly peaks of temperature and pressure is generated by the separation bubble. These position of peak condition are influence by the self induced oscillation.(5) The time average pressure at the cross position of the jet are decrease for increment of the pressure ration and the position of plate.(6) The changes of boundary layer curvature is observed at the interaction point of the upper and lower tail shock waves with the inclined wall and it is due to the generation of separation bubble.(7) The peak temperature on the axis of inclined surface is generated due to the change of thickness of boundary layer together with the temperature peak occur by the shock wave interacted with wall.(8) The temperature along the nozzle axis are increases with the increment of roughness of surface.