Physical Interpretation of the Influence of a DC Discharge on a Supersonic Rarefied Flow over a Flat Plate

The present work is an attempt to clarity the physical interpretation of the change in flow parameters and dynamic loads induced by an electric discharge in the vicinity of a flying body. The particular case considered here is the flow along a sharp flat plate in a low-density flow at Mach 2. The problem has been studied both experimentally and numerically. It is concluded that the change in wall temperature due to the discharge explains best the changes observed in the transverse profiles of Pitot pressure. The observed changes in dynamic loads due to the discharge cannot be explained by the distribution of wall normal and tangential stresses. Coulomb forces between the gas and the electrodes mounted on the wall are probably also involved.