Numerical analysis of attack angle effects on 3D supersonic turbulent flow around of blunt body along with opposite jet injection

In this study, the effects of attack angle in opposing jet injection through supersonic blunt bodies on drag reduction and distribution of surface temperature is studied through developing a three dimensional multi-block code. Inviscid terms are calculated by AUSM scheme. The viscous terms is obtained by central difference method and using 4-stage Rung-Kutta algorithm, integral time is computed. Shear stress transport model is used to simulate the effects of turbulence. The effects of pressure ratio and properties of flow field have been verified and validated with experimental and numerical results of other researchers which is indicator of method accuracy. The results show that the sonic jet injection is able to significantly reduce drag nose by changing the shape of the bow shock and it also prevents a sharp increase in the surface temperature by covering the body. Increasing the total pressure ratio, improved performance of jet in both drag reduction and distribution of surface temperature. However due to the sharp increase in retro propulsion of jet there is a limitation in increasing the ratio of total pressure. In addition, the increase of pressure ratio will reduce the friction coefficient. Angle of attack of the free stream reduces the efficiency of the jet injection. Although in this situation the result can be improved to somehow by paralleling the jet and free stream.