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arXiv · 1407.6855

Energy transfers in dynamos with small magnetic Prandtl numbers

Rohit Kumar·Mahendra K. Verma·Ravi Samtaney
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Abstract

We perform numerical simulation of dynamo with magnetic Prandtl number $\mathrm{Pm} =0.2$ on $1024^3$ grid, and compute the energy fluxes and the shell-to-shell energy transfers. These computations indicate that the magnetic energy growth takes place mainly due to the energy transfers from large-scale velocity field to large-scale magnetic field and that the magnetic energy flux is forward. The steady-state magnetic energy is much smaller than the kinetic energy, rather than equipartition; this is because the magnetic Reynolds number is near the dynamo transition regime. We also contrast our results with those for dynamo with $\mathrm{Pm} =20$ and decaying dynamo.

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Rohit Kumar, Mahendra K. Verma, Ravi Samtaney. 2014-07-25. Energy transfers in dynamos with small magnetic Prandtl numbers. https://doi.org/10.1080/14685248.2015.1057340

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