Investigation on Oblique Shock Wave Control by Surface Arc Discharge in a Mach 2.2 Supersonic Wind Tunnel

Abstract

A shock wave is a typical aerodynamic phenomenon in a supersonic flow, and if controlled effectively, a series of potential applications can be achieved in aerospace fields, such as reducing wave drag and sonic boom of the supersonic vehicle, optimizing shock waves of the supersonic inlet in off-design operation states, decreasing pressure loss induced by shock waves in the supersonic wind tunnel or aeroengine internal duct, controlling shock waves of the wave rider, changing shock wave symmetry to achieve flight control and inducing shock waves in the aeroengine nozzle to achieve thrust vector control. Shock wave control can be achieved by many mechanical or gas dynamic methods, such as the ramp angle control in supersonic inlet and the holl/cavum control in self-adapted transonic wing. Because the structural configurations of these methods are somewhat complex and the flow control response is also slow, plasma flow control based on gas discharge physics and electromagnetohydrodynamics (EMHD) theory has been developed recently in the shock wave control field. Using this method, substantial thermal energy can be added in the shock wave adjacent areas, then the angle and intensity of shock wave change subsequently. Meyer et al investigated whether shock wave control by plasma aerodynamic actuation is a thermal mechanism or an ionization mechanism, and the experimental results demonstrated that the thermal mechanism dominates the shock wave control process [1, 2]. Miles et al investigated the shock wave control by laser energy addition experimentally and numerically, and the research results showed that when the oblique shock wave passed by the thermal spot induced by laser ionization, the shock wave shape distorted and the shock wave intensity reduced [3]. Macheret et al proposed a new method of virtual cowl induced by plasma flow control which can optimize the shock waves of supersonic inlet when its operation Mach number is lower than the design Mach number [4]. Meanwhile, they used the combination method of e-beam ionization and magnetohydrodynamic (MHD) flow control to optimize the shock waves of supersonic inlet when operating in off-design states, and the research results demonstrated that the shock waves can reintersect in the cowl adjacent area in different off-design operation states with the MHD acceleration method and the MHD power generation method, respectively [5]. Leonov et al used a quasi-dc