Nonlinear tearing mode study using the 'almost ideal magnetohydrodynamics (MHD)' constraint

摘要

Tearing modes of finite amplitude are studied numerically using the "almost ideal magnetohydrodynamics (MHD)" constraint, which is a modification of the ideal MHD constraints that allows reconnection of the magnetic field lines. For the one-dimensional initial equilibria studied here, the stability criterion is found to be the same as that of the linear tearing mode theory, namely Delta' < 0. The nonlinear saturation level of the mode can also be determined; it is found to be smaller than that estimated from Delta'(W-sat) = 0 [R. B. White et al., Phys. Fluids 20, 800 (1977)]. (C) 1998 American Institute of Physics. [S1070-664X(48)02907-3] [References: 13]