Kelvin-Helmholtz instability and collapse of a twisted magnetic null point with anisotropic viscosity

Context: Magnetic null points are associated with high-energy coronal phenomena such as solar flares and often sites of reconnection particle acceleration. Dynamic twisting a magnetic point can generate Kelvin-Helmholtz instability (KHI) within its fan plane and, under continued twisting, instigate spine-fan an collapse the point. Aim: This article aims to compare effects isotropic anisotropic viscosity in simulations KHI dynamically twisted Methods: Simulations were performed using 3D magnetohydrodynamics code Lare3d custom module. A pair high resolution was performed, one another viscosity, keeping all other factors identical, results analysed detail. further parameter study over range values for resistivity. Results: Both models permit growth eventual Over studied parameters, allows faster growing instability, while damps extent stabilisation some cases. Although viscous heating is generally smaller, ohmic dominates enhanced by current sheets generated leading greater overall rate when viscosity. The occurs significantly sooner employed.