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arXiv · 1904.00225

Rossby and Magnetic Prandtl Number Scaling of Stellar Dynamos

K. ~C. Augustson·A. ~S. Brun·J. Toomre
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Abstract

Rotational scaling relationships are examined for the degree of equipartition between magnetic and kinetic energies in stellar convection zones. These scaling relationships are approached from two paradigms, with first a glance at scaling relationship built upon an energy-balance argument and second a look at a force-based scaling. The latter implies a transition between a nearly-constant inertial scaling when in the asymptotic limit of minimal diffusion and magnetostrophy, whereas the former implies a weaker scaling with convective Rossby number. Both scaling relationships are then compared to a suite of 3D convective dynamo simulations with a wide variety of domain geometries, stratifications, and range of convective Rossby numbers.

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K. ~C. Augustson, A. ~S. Brun, J. Toomre. 2019-03-30. Rossby and Magnetic Prandtl Number Scaling of Stellar Dynamos. https://doi.org/10.3847/1538-4357%2Fab14ea

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