1 EXTERNAL SUPERSONIC FLOW AND SCRAMJET INLET CONTROL BY MHD WITH ELECTRON BEAM IONIZATION

The paper examines the possibility of controlling scramjet inlets in off-design conditions by operating a near-surface MHD system upstream of the inlet. The required electrical conductivity in air is supposed to be created by electron beams injected into the air from the vehicle along magnetic field lines. A simple model of beam-generated ionization profile is developed and coupled with plasma kinetics, MHD equations, and 2D inviscid flow equations. Calculations show that an MHD system with reasonable parameters could bring shocks back to the cowl lip when flying at Mach numbers higher than those for which the inlet was optimized. The MHD effect is not reduced to heating only, as the work by j B× GG forces is a substantial part of the overall effect. Power requirements for ionizing e-beams could be lower than the electrical power extracted with MHD, so that a net power would be generated on board. Problems associated with high Hall fields are discussed. 1