Direct Numerical Simulation of the Pulsed Arc Discharge in Supersonic Compression Ramp Flow

Abstract

Direct numerical simulation (DNS) of shock wave/turbulent boundary layer interaction (SWTBLI) with pulsed arc discharge is carried out in this paper. The subject in the study is a Ma=2.9 compression flow over a 24-degree ramp. The numerical approaches were validated by the experimental results in the same flow conditions. The heat source model was added to the Navier-Stokes equation to serve as the energy deposition of the pulsed arc discharge. Four streamwise locations are selected to apply energy deposition. The effect of the pulsed arc discharge on the ramp-induced flow separation has been studied in depth. The DNS results demonstrate the incentive locations play a dominant role in suppressing the separated flow. Results show that pulsed heating is characterized by a thermal blockage, which leads to streamwise deflection. The incentive locations upstream the interaction zone of the base flow have a better control effect. The separation bubble shape shows as “spikes”, and the downstream flow of the heated region is accelerated due to the momentum exchange between the upper boundary layer and the bottom boundary layer. The high-speed upper fluid is transferred to the bottom, and thus enhances its ability to resist the flow separation. More stripe vortex structures are also generated at the edge of the flat-plate. Furthermore, the turbulent kinetic disturbance energy is increased in the flow filed. The disturbances that originate from the pulsed heating are capable of increasing the turbulent intensity and then diminishing the trend of flow separation.