Magnetohydrodynamics of Flows in MHD Ducts

The paper discusses problems of the magnetic hydrodynamics of flows with hot electrons in MHD ducts at low magnetic Reynolds numbers. The work deals principally with boundary-layer and shock-wave theory. In connection with boundary layer theory, the conditions of the occurrence of detachment and the jump in density associated with it are discussed for a supersonic flow. The methods of preventing detachment are discussed; in particular the required degree of exhaustion of the plasma from the boundary layer is calculated. Attention is also given to wave resistance to a supersonic flow which arises from the uneven distribution of the current on the electrode wall of the duct. In connection with the theory of shock waves in a plasma with hot electrons, the structure of these waves in relation to the rate of ionization is considered, together with their stability. The problems related to the appearance of parasitic closed currents, with a strong reduction in conductivity of the plasma beyond the shock-wave front and a change in the regime to accelerating, are also dealt with. (author)