Nonlinear Evolution of Resistive Interchange Modes in Reversed Field Pinches

摘要

The results are presented of the application of a two dimensional resistive MHD computer code to the nonlinear evolution of resistive interchange modes in tearing-mode-stable RFP equilibria. One finds that the m = 1 mode is insignificant when the singular surface is outside the field reversal point, and is more active nonlinearly but still fairly localized when the singular surface lies in the inner regions of the plasma. The m = 0 mode, which is not present in tokamaks, is found to lead to highly distorted flux surfaces and interchange vortices of large radial extent when beta is near the Suydam marginal point. However, if the initial beta is sufficiently small, this mode remains localized allowing significant Ohmic heating of the pinch to occur. (ERA citation 05:023344)