Magnetohydrodynamic interaction in the shock layer of a wedge in a hypersonic flow

This paper describes the results of an experimental investigation on the effect of magnetohydrodynamic (MHD) interaction with the plasma of the shock layer at a test body in a hypersonic argon flow. The hypersonic flow is obtained from the high-enthalpy arc-heated wind tunnel of Alta, Pisa, Italy, on Mach 6. Tests are carried out at heating chamber stagnation pressures of 0.65, 0.85, and 1 bar and magnetic fields of 0.15-0.35 T. The experimental observations are done by means of a set of electrical probes, an optical multichannel analyzer, and a fast shutter charge-coupled device camera. In order to maximize the effect of MHD interaction, the Faraday field is shorted, and a magnetic field perpendicular to the test body surface is used. An increase of the distance between the shock front and the body, owing to the MHD interaction, is observed. The MHD interaction effect is reduced by the low conductivity of the plasma in the boundary layer at the test body surface.