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arXiv · 1304.6212

Intermittency in spherical Couette dynamos

Raphaël Raynaud·Emmanuel Dormy
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Abstract

We investigate dynamo action in three-dimensional numerical simulations of turbulent spherical Couette flows. Close to the onset of dynamo action, the magnetic field exhibits an intermittent behavior, characterized by a series of short bursts of the magnetic energy separated by low-energy phases. We show that this behavior corresponds to the so-called on-off intermittency. This behavior is here reported for dynamo action with realistic boundary conditions. We investigate the role of magnetic boundary conditions in this phenomenon.

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Raphaël Raynaud, Emmanuel Dormy. 2013-04-23. Intermittency in spherical Couette dynamos. https://doi.org/10.1103/physreve.87.033011

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