A parallel semi-implicit method for 3D nonlinear magnetohydrodynamics

An efficient parallel semi-implicit method for solving the three-dimensional nonlinear equations of magnetohydrodynamics (MHD) is presented. This three-dimensional model is extremely powerful and can be applied for the simulation of MHD phenomena in magnetic confinement devices as well as astrophysical plasmas, e.g. solar coronal loops. The parallel aspects of the method, such as the scaling with the number of processors, are illustrated on the connection machine CM-5 (peak node performance: 128 Mflops) and on the Cray-T3D (peak node performance 150 Mflops). The parallel implementation allows MHD simulations for magnetic Reynolds numbers that are two orders of magnitude higher than the currently used values and this results in a better description of the processes in the solar corona and magnetic confinement devices (tokamaks). The parallel code is applied to calculate ideal and resistive instabilities and plasma filament dynamics in magnetic confinement devices and MHD wave heating of coronal loops.