Convergence of an unconditionally stable semi-implicit scheme for linear incompressible MHD equations

Semi-implicit methods have been introduced by Harned et al. to solve magnetohydrodynamic equations (MHD) with numerical schemes which are unconditionally stable with respect to fast and shear Alfven modes. They prove the stability of their scheme for Linear ideal MHD equations with periodic boundary conditions, and with some technical assumptions.' In this paper, we prove convergence of the numerical approximation (time discretization), under the same hypothesis, but looking for solutions on any regular bounded open set of R-3 With appropriate boundary conditions, and introducing finite resistivity and viscosity. (C) Academie des Sciences/Elsevier, Paris.