International Astronomy and Astrophysics Research Journal

On the Interaction of Buoyant Magnetic Structures with Convective Plumes

Abrar A. Ali *

Department of Mathematics and Physics, the Australian University, P.O. Box 1411, Safat 13015, Kuwait.

Lara J. Silvers

Department of Mathematics, City, University of London, Northampton Square, London, EC1V 0HB, UK.

*Author to whom correspondence should be addressed.

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Abstract

Motivated by the tachocline region within the Sun, we investigate the interaction of buoyant structures with convection in a numerical set-up that resembles the base of the solar convection zone, where the fully compressible, non-linear magnetohydrodynamics equations are solved. Fully-developed convective flows are prescribed, with particular attention paid to identifying the features established in the earlier studies of [1] and [2] where parameterisation of the small-scale turbulent pumping is imposed using mean-field approximation. Analysis of several magnetoconvection regimes in quasi-two-dimensions reveals that the equipartition criterion between kinetic and magnetic energy does contribute globally to the flux emergence process as fluctuating motions in turbulent flows become more energetic. However, results were found to be less pronounced in the three-dimensional simulations due to the effectively reduced fluctuations.

Keywords: Convection, instabilities, MHD, Sun: interior, Sun: magnetic fields

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