Abstract:
The main objective of this study is to demonstrate the feasibility of actively influencing the position of the bow shock wave in a supersonic flow, as well as the parameters of an aerodynamic body, using a gas discharge generated near the frontal surface between the body and the bow shock wave. The dependence of the steady bow shock wave stand-off distance on the discharge power and current in xenon and air was studied experimentally and numerically. A comparison of the numerical and experimental data showed good agreement. It was found that the position of the steady bow shock wave is determined by the specific discharge power and the adiabatic index (affected by the degree of ionization and the degree of nonequilibrium) in the plasma zone created by the discharge. It was found that, at the initial stage, the dependence of the relative stand-off on the discharge power is close to linear, while the adiabatic index is close to constant. As the discharge current and power increase, the adiabatic index tends to increase in xenon and decrease in air. At the same time, an oscillatory dependence of the position of the steady bow shock wave on the discharge power was observed in xenon. This oscillation is associated with the possibility of the adiabatic index either increasing or decreasing depending on the correlation of plasma characteristics. Thus, it was shown that the adiabatic index of a gas-discharge plasma plays a significant role in the dynamics of the flow structure and the magnitude of the stand-off position of the steady bow shock wave from the body. The obtained results can be used in developing high-speed flow control systems, taking into account not only thermal effects but also the influence of plasma parameters.