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arXiv · 2405.15331

Material Barriers to the Diffusive Magnetic Flux in Magnetohydrodynamics

A. Encinas-Bartos·B. Kaszás·S. Servidio·G. Haller
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Abstract

Recent work has identified objective (frame-indifferent) material barriers that inhibit the transport of dynamically active vectorial quantities (such as linear momentum, angular momentum and vorticity) in Navier-Stokes flows. In magnetohydrodynamics (MHD), a similar setting arises: the magnetic field vector impacts the evolution of the velocity field through the Lorentz force and hence is a dynamically active vector field. Here, we extend the theory of active material barriers from Navier-Stokes flows to MHD flows in order to locate frame-indifferent barriers to the diffusive transport of the magnetic field in turbulent two-dimensional and three-dimensional MHD flows. From this approach we obtain an algorithm for the automated extraction of such barriers from MHD turbulence data.

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A. Encinas-Bartos, B. Kaszás, S. Servidio, G. Haller. 2024-05-24. Material Barriers to the Diffusive Magnetic Flux in Magnetohydrodynamics. https://arxiv.org/abs/2405.15331

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