Universal nonlinear small-scale dynamo.

  title={Universal nonlinear small-scale dynamo.},
  author={Andrey Beresnyak},
  journal={Physical review letters},
  volume={108 3},
  • A. Beresnyak
  • Published 21 September 2011
  • Physics
  • Physical review letters
We consider astrophysically relevant nonlinear MHD dynamo at large Reynolds numbers (Re). We argue that it is universal in a sense that magnetic energy grows at a rate which is a constant fraction C(E) of the total turbulent dissipation rate. On the basis of locality bounds we claim that this "efficiency of the small-scale dynamo", C(E), is a true constant for large Re and is determined only by strongly nonlinear dynamics at the equipartition scale. We measured C(E) in numerical simulations and… 

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