# Universal nonlinear small-scale dynamo.

@article{Beresnyak2012UniversalNS, title={Universal nonlinear small-scale dynamo.}, author={Andrey Beresnyak}, journal={Physical review letters}, year={2012}, volume={108 3}, pages={ 035002 } }

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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