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arXiv · 1807.01986

Nonlinear dynamo in obliquely rotating stratified electroconductive fluid in an uniformly magnetic field

M. I. Kopp·K. N. Kulik·A. V. Tur·V. V. Yanovsky
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Abstract

We study a new type of large-scale instability, which arises in obliquely rotating stratified electroconductive fluid with an external uniform magnetic field and a small-scale external force having zero helicity. This force gives rise to small-scale oscillations of the velocity with a small Reynolds number. Using the method of multi-scale asymptotic expansions there are obtained nonlinear equations for vortex and magnetic perturbations in the third order in Reynolds number. Studied is the linear stage of magneto-vortex dynamo caused by instabilities of $\alpha$-effect type. Stationary solutions for the equations of nonlinear magneto-vortex dynamo are found by numerical methods in the form of localized chaotic structures.

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M. I. Kopp, K. N. Kulik, A. V. Tur, V. V. Yanovsky. 2018-07-03. Nonlinear dynamo in obliquely rotating stratified electroconductive fluid in an uniformly magnetic field. https://arxiv.org/abs/1807.01986

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