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arXiv · 2212.00969

Energy pathways in large- and small-scale convection-driven dynamos

Souvik Naskar·Anikesh Pal
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Abstract

We investigate the energy pathways between the velocity and the magnetic fields in a rotating plane layer dynamo driven by Rayleigh-B\'enard convection using direct numerical simulations. The kinetic and magnetic energies are divided into mean and turbulent components to study the production, transport, and dissipation associated with large and small-scale dynamos. This energy balance-based characterization reveals distinct mechanisms for large- and small-scale magnetic field generation in dynamos, depending on the nature of the velocity field and the conditions imposed at the boundaries.

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Souvik Naskar, Anikesh Pal. 2022-12-02. Energy pathways in large- and small-scale convection-driven dynamos. https://arxiv.org/abs/2212.00969

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