Numerical Simulations of Solar Active Region Magnetoconvection

Vigorous fluid motions associated with the observed patterns of supergranulation, mesogranulation, and granulation on the sun are likely to play a large role in the continual emergence, evolution, and redistribution of magnetic field within solar active regions. To investigate such non-linear dynamics, we have constructed numerical simulations of fully compressible magnetized fluids, each contained within curved, spherical segments nominally located near the top of the solar convection zone. Overturning motions having length scales comparable to that of solar supergranulation are driven by imposing a solar-like heat flux through the bottom of the domain. We present recent results of several idealized active region simulations within thin spherical segments, each spanning 60°x 30° in longitude and latitude and extending up to 0.04~R_sun in radius. We are able to investigate the analogs of both plage and active regions by varying the amount of magnetic flux that permeates the layer. Simplified field-line extrapolations into the volume above the spherical segments are then used to assess how the corona might respond to the structure and evolution of magnetic field emerging through the solar photosphere. This work was supported by NASA through grant NAG 5-3077 to Stanford University and by Lockheed Martin Independent Research and Development funds.