TIME AND SPACE SCALES OF ELECTRICAL AND GASDYNAMIC NONUNIFORMITIES INA NONEQUILIBRIUM MHD PLASMA

The Saha equilibrium approximation and the temperature relaxation appr oximation to the MHD equations are investigated with regard to the ana lysis of the formation of nonlinear ionization non-uniformities and th eir evolution in a nonequilibrium MHD plasma, An analysis of character istic relaxation times under typical plasma parameters is carried out to verify these approximations. Characteristic space scales of electro n thermal conductivity and radiation are evaluated, These space scales determine the characteristic width of nonlinear ionization wave front s, and are important for the application of numerical simulations.