Magnetohydrodynamic Simulation of Solar Supergranulation

Abstract

Three-dimensional magnetohydrodynamical large eddy simulations of solar surface convection using realistic model physics is conducted. The effects of magnetic fields on thermal structure of convective motions into radiative layers, the range of convection cell sizes and penetration depths of convection is investigated. We simulate a some portion of the solar photosphere and the upper layers of the convection zone, a region extending 30 x 30 Mm horizontally from 0 Mm down to 18 Mm below the visible surface. We solve equations of the fully compressible radiation magnetohydrodynamics with dynamical viscosity and gravity. For numerical simulation we use: 1)realistic initial model of Sun and equation of state and opacities of stellar matter, 2) high order conservative TVD scheme for solution magnetohydrodynamics, 3) diffusion approximation for solution radiative transfer 4) calculation dynamical viscosity from subgrid scale modelling. Simulations are conducted on horizontal uniform grid of 320 x 320 and with 144 nonuniformly spaced vertical grid points on the 128 processors of supercomputer MBC-1500 with distributed memory multiprocessors in Russian Academy of Sciences.