Nonlinear motion of non–uniform current–vortex sheets in MHD Richtmyer–Meshkov instability

Abstract

Nonlinear motion of a vortex sheet initially applied a homogeneous magnetic field is investigated using the vortex blob method. We show that the existence of a vortex sheet induces a strong magnetic field and non-uniform current at the fluid interface. This system can be a model of incompressible magnetohydrodynamic Richtmyer–Meshkov instability (MHD-RMI). We present some interfacial profiles in MHD-RMI and discuss the difference between the pure vortex sheet in standard RMI and the current–vortex sheet in MHD-RMI, in which it is shown that the magnetic field suppresses the roll-up of the vortex sheet. We also find that the strong magnetic field amplification is caused by the stretch of the interface.