Study on Nonequilibrium Plasma Discharge in Hypersonic Flow over Flat Plate

Abstract

Hypersonic flow control with plasma discharge has received a good deal of research attention in recent years. In this study, the direct current (DC) plasma discharge over a flat plate was investigated as a prospective futuristic aerodynamic control device. Spectroscopic analysis showed that the vibrational temperature of nitrogen molecule is 7000 K and the translational temperature is 3500 K at maximum, which suggested that the plasma is at a vibrationally nonequilibrium state. Since electromagnetic forces for the futuristic aerodynamic control can mainly be imposed on ionized molecules, a numerical analysis was conducted based on Park’s Two-temperature model and Gupta’s 11-species model in order to estimate the distribution of high vibrational-temperature region. It was revealed that the concentration of high-vibrational temperature region exists in the boundary layer over flatplate surface, which is consistent with the experimental result of vibrationally exited nitrogen molecular distribution.