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arXiv · 2212.04230

Alpha-effect in three-dimensional coherent vortex of conducting rotating liquid

Leon L. Ogorodnikov·Sergey S. Vergeles
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Abstract

We study one-point statistics of spiral turbulent pulsations on the background of three-dimensional large-scale vortex in a rotating fluid. Assuming that the helical flow is created by a statistically axially symmetric random force with broken mirror symmetry, we analytically calculate velocity-vorticity mean including its magnitude and the anisotropy. For electrically conducting liquid, we examine the $α$-effect in the system. The found elements of $α$-matrix strongly depend on relation between Rossby $\mathrm{Ro}$ and magnetic Prandtl $\mathrm{Pr}_{\mathrm{m}}$ numbers in considered region $\mathrm{Ro}\lesssim 1$, $\mathrm{Pr}_{\mathrm{m}} \lesssim 1$. We establish criterion for the numbers when the $α$-effect leads to instability of large-scale magnetic field

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Leon L. Ogorodnikov, Sergey S. Vergeles. 2023-10-29. Alpha-effect in three-dimensional coherent vortex of conducting rotating liquid. https://arxiv.org/abs/2212.04230

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