An approach to calculation of magnetic island rotation frequency

The problem of magnetic island rotation is analyzed. It is noted that for the correct solution of this problem the nonstationarity of profile functions should be taken into account. An approach to solving equations for nonstationary profile functions is developed for cases when drift and neoclassical effects can be neglected. The principal role of perpendicular viscosity in determining island rotation frequency is emphasized. The possibility of the existence of stationary magnetic islands in tokamaks with a rotating plasma and a resistive wall is shown.