High-speed aerodynamics control using energy injection of pulsed discharges

We present a novel method of high-speed aerodynamic control that relies on active energy injection of pulsed discharges characterized by a high power density and long pulse width. The control principle, which is based on the manipulation of a shock wave by the energy injection, is investigated and verified via M5 wind tunnel experiments and a numerical simulation. The test model is a cone-shaped model with two compression ramps, and we organize four discharges which are connected in series and located on the surface of the model. We use high-resolution schlieren imaging and a fiber optic balance to analyze the control effects of these discharges on the flow topology and the aerodynamic force. Schlieren imaging reveals a notable change in the flow topology and a weakening of the attached shock wave due to the discharge plasma layer creating a virtual wedge that diverts the incoming flow and reducing the local Mach number. The quantitative balance data show a significant force reduction in the presence of the pulsed discharges, and reveals that the force reduction rate is associated with the energy ratio, which increases with an increase in the pulse energy and a decrease in the dynamic pressure. A larger energy ratio of discharge leads to a higher penetration depth of the plasma layer, which is more conducive to aerodynamic control. The simulation results show similar flow topologies and consistent variation tendency in the aerodynamic force to the experimental results.(c) 2023 Elsevier Masson SAS. All rights reserved.