Internal disruption in high β/sub p/ tokamak

The m = 1 MHD activity is investigated from the viewpoint of the suppression of the internal disruption and the appearance of large amplitude oscillations observed in the recent high β tokamak experiment. The stabilization of the m = 1 internal kink mode by the toroidal effect is confirmed by using the revised version of ERATO. The nonlinear evolution of the resistive internal kink mode is investigated and the reasonable saturation of the m = 1 magnetic island is obtained by using the new reduced set of equations. The effect of the toroidal coupling between the m = 1 and m = 2 tearing modes is also studied. The m = 2 mode is strongly affected, but the saturation of the m = 1 magnetic island is not realized