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arXiv · 1311.6502

A simplified model of collision-driven dynamo action in small bodies

Xing Wei·Rainer Arlt·Andreas Tilgner
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Abstract

We investigate numerically the self-sustained dynamo action in a spinning sphere whose sense of rotation reverses periodically. This system serves as a simple model of a dynamo in small bodies powered by frequent collisions. It is found that dynamo action is possible in some intervals of collision rates. At high Ekman numbers the laminar spin-up flow is helical in the boundary layers and the Ekman circulation together with the azimuthal shear powers the dynamo action. At low Ekman number a non-axisymmetric instability helps the dynamo action. The intermittency of magnetic field occurs at low Ekman number.

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BibTeXRIS

Xing Wei, Rainer Arlt, Andreas Tilgner. 2013-11-25. A simplified model of collision-driven dynamo action in small bodies. https://doi.org/10.1016/j.pepi.2014.03.004

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