Dynamo enhancement and mode selection triggered by high magnetic permeability
arXiv:1706.00260 · doi:10.1103/PhysRevLett.119.234501
Abstract
We present results from consistent dynamo simulations, where the electrically conducting and incompressible flow inside a cylinder vessel is forced by moving impellers numerically implemented by a penalization method. The numerical scheme models jumps of magnetic permeability for the solid impellers, resembling various configurations tested experimentally in the von-Karman Sodium experiment. The most striking experimental observations are reproduced in our set of simulations. In particular, we report on the existence of an axisymmetric dynamo mode, self-consistently generated when the magnetic permeability of the impellers exceeds a threshold. We describe a possible scenario involving both the turbulent flow in the vicinity of the impellers and the high magnetic permeability of the impellers.
5 pages, 4 figures
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Cited by in corpus (5)
- Dynamo theories
- Axisymmetric dynamo action produced by differential rotation, with anisotropic electrical conductivity and anisotropic magnetic permeability
- Enhanced dynamo growth in nonhomogeneous conducting fluids
- Fast and Furious dynamo action in the anisotropic dynamo
- Laboratory experiments on dynamo action and magnetically triggered flow instabilities