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arXiv · 0711.1237

Phenomenology of turbulent dynamo growth and saturation

Rodion Stepanov·Franck Plunian
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Abstract

With a non local shell model of magnetohydrodynamic turbulence we investigate numerically the turbulent dynamo action for low and high magnetic Prandtl numbers ($Pm$). The results obtained in the kinematic regime and along the way to dynamo saturation are understood in terms of a phenomenological approach based on the local ($Pm\ll 1$) or non local ($Pm\gg 1$) nature of the energy transfers. In both cases the magnetic energy grows at small scale and saturates as an inverse `` cascade ''.

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Rodion Stepanov, Franck Plunian. 2007-11-08. Phenomenology of turbulent dynamo growth and saturation. https://doi.org/10.1086/587795

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