Energy transfers in dynamos with small magnetic Prandtl numbers

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.

20 pages, 16 figures

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Cited by in corpus (3)

• Amplification of large-scale magnetic field in nonhelical magnetohydrodynamics
• Dynamo transition in a five-mode helical model
• Magnetohydrodynamic Turbulence: Chandrasekhar's Contributions \& Beyond