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arXiv · 1811.00859

Pointwise vanishing velocity helicity of a flow does not preclude magnetic field generation

Alexander Andrievsky·Roman Chertovskih·Vladislav Zheligovsky
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Abstract

Pointwise zero velocity helicity density is shown not to prevent steady flows from acting as kinematic dynamos. We present numerical evidences that such flows can generate both small-scale magnetic fields as well as, by the magnetic $α$-effect or negative eddy diffusivity mechanisms, large-scale ones. The flows are constructed as curls of analytically defined space-periodic steady solenoidal flows, whose vorticity helicity (i.e., kinetic helicity) density is everywhere zero.

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Alexander Andrievsky, Roman Chertovskih, Vladislav Zheligovsky. 2019-02-26. Pointwise vanishing velocity helicity of a flow does not preclude magnetic field generation. https://doi.org/10.1103/physreve.99.033204

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