Magnetic energy dissipation and mean magnetic field generation in planar convection driven dynamos

TL;DR

This study investigates magnetic energy dissipation and mean magnetic field generation in rotating convective plane layer dynamos, revealing differences from spherical shell models and confirming the coexistence of dynamos with and without mean fields.

Contribution

It provides new insights into the scaling laws of magnetic energy and dissipation in planar convection dynamos, contrasting with spherical shell results.

Findings

Magnetic energy scales differently with flux Rayleigh number compared to spherical models.

Magnetic dissipation length dependence on magnetic Reynolds number is similar across geometries.

Both mean field and non-mean field dynamos exist in rapidly rotating plane layers.

Abstract

A numerical study of dynamos in rotating convecting plane layers is presented which focuses on magnetic energies and dissipation rates, and the generation of mean fields (where the mean is taken over horizontal planes). The scaling of the magnetic energy with the flux Rayleigh number is different from the scaling proposed in spherical shells, whereas the same dependence of the magnetic dissipation length on the magnetic Reynolds number is found for the two geometries. Dynamos both with and without mean field exist in rapidly rotating convecting plane layers.