Relaxation of 2D MHD flow transverse to a magnetic field in a bounded domain

Summary form only given. MHD plasma flow transverse to a magnetic field in a bounded domain, initially set in a form of a sole vortex, is solved numerically. This problem is of interest for dynamic magnetized plasma systems such as the MAGO/MTF system. For plasma subsequent compression issues in that systems it is important to know how long the hydrodynamic motion is conserved in them. It can result in convective plasma cooling and impurities entering into the plasma due to walls washing by this flow. A case of large Reynolds number (and large magnetic Reynolds) and small Alfven-Mach number MA is considered, so it is assumed that initial magnetosonic shock wave relaxation already occured. In this case the MHD problem reduces to a problem of 2D hydrodynamic turbulence. Calculations showed that in accordance with results of 2D turbulence and in difference with 3D turbulence results a kinetic energy dissipation goes very slowly for small MA, during time /spl sim/L/sup 2//&nu (L is a characteristic system size, &nu is a kinematic viscosity). While MA is not too small the kinetic energy dissipation is caused by magnetosonic waves emission and their subsequent nonlinear (shock wave) damping.