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On the Saturation of Astrophysical Dynamos: Numerical Experiments with the No-Cosines Flow

Abstract

In the context of astrophysical dynamos we illustrate that the no-cosines flow, with zero mean helicity, can drive fast dynamo action and we study the dynamo’s mode of operation during both the linear and non-linear saturation regimes. It turns out that in addition to a high growth rate in the linear regime, the dynamo saturates at a level significantly higher than normal turbulent dynamos, namely at exact equipartition when the magnetic Prandtl number Prm∼ 1. Visualization of the magnetic and velocity fields at saturation will help us to understand some of the aspects of the non-linear dynamo problem.

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Correspondence to S. B. F. Dorch.

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Dorch, S.B.F., Archontis, V. On the Saturation of Astrophysical Dynamos: Numerical Experiments with the No-Cosines Flow. Sol Phys 224, 171–178 (2004). https://doi.org/10.1007/s11207-005-5700-4

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  • DOI: https://doi.org/10.1007/s11207-005-5700-4

Keywords

  • Growth Rate
  • Numerical Experiment
  • Velocity Field
  • High Growth
  • Prandtl Number