Control of Pseudo-Shock by Slot Injection

Abstract

It is well known that the boundary layer separation due to the adverse pressure gradient of the pseudo-shock affects the dynamic feature of the pseudo-shock such as the shape of the first shock, the pressure recovery and the self-induced oscillation. The suppression of the separation is effective to control the interaction between the shock wave and the boundary layer. In this research, the boundary layer control with the slot injection is studied experimentally and numerically. The experiment is carried out in a blow-down supersonic wind tunnel at free stream Mach number of 2.0. The numerical simulation is made with the two-dimensional compressible Navier-Stokes code. In solving the equations, the second-order accurate Harten-Yee's upwind TVD scheme and k-ε turbulence model modified for the compressible flow are used. The results show that the separation is appreciably suppressed and the shape of the first shock is changed, resulting the wall pressure fluctuation to be greatly reduced. Furthermore the total pressure loss is decreased with the low slot height.