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arXiv · 0904.3343

Chaotic magnetic field reversals in turbulent dynamos

Christophe Gissinger·Emmanuel Dormy·Stephan Fauve
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Abstract

We present direct numerical simulations of reversals of the magnetic field generated by swirling flows in a spherical domain. In agreement with a recent model, we observe that coupling dipolar and quadrupolar magnetic modes by an asymmetric forcing of the flow generates field reversals. In addition, we show that this mechanism strongly depends on the value of the magnetic Prandtl number.

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Christophe Gissinger, Emmanuel Dormy, Stephan Fauve. 2009-04-21. Chaotic magnetic field reversals in turbulent dynamos. https://doi.org/10.1209/0295-5075%2F90%2F49001

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