Current state and potentialities of hypersonic MHD-gas acceleration wind tunnels

Developments of hypersonic wind tunnels with MHD-gas accelerators were initiated late in the 1950s when limited capabilities of classical hypersonic wind tunnels based on the test gas acceleration due to its adiabatic expansion became obvious. These studies were started almost at the same time in the USA (NASA, Langley Research Center, AEDS, General Electric Company) and in Russia (TsAGI). Some works were carried out in France (ONERA) and in Germany. The present review analyzes different designs of this facility. Main characteristics of the hypersonic wind tunnel of TsAGI and the results of its application to solve practical problems of aerodynamics are considered. The flow conditions over bodies in a free flight are compared with those realized experimentally in the test section of the facility at the same flow velocities of V/spl sim/8 km/s. The advantage of applying MHD-gas acceleration facilities to solve problems of developing and testing scramjets for TAV vehicles is demonstrated and the data on possible gas dynamic and electrodynamic parameters of these facilities and their design versions are presented. Finally, basic problems to be solved in developing hypersonic MHD-gas acceleration facilities are listed.