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arXiv · 0806.3872

Reduction of velocity fluctuations in a turbulent flow of gallium by an external magnetic field

Michael Berhanu·Basile Gallet·Nicolas Mordant·Stephan Fauve
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Abstract

The magnetic field of planets or stars is generated by the motion of a conducting fluid through a dynamo instability. The saturation of the magnetic field occurs through the reaction of the Lorentz force on the flow. In relation to this phenomenon, we study the effect of a magnetic field on a turbulent flow of liquid Gallium. The measurement of electric potential differences provides a signal related to the local velocity fluctuations. We observe a reduction of velocity fluctuations at all frequencies in the spectrum when the magnetic field is increased.

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Michael Berhanu, Basile Gallet, Nicolas Mordant, Stephan Fauve. 2008-06-24. Reduction of velocity fluctuations in a turbulent flow of gallium by an external magnetic field. https://doi.org/10.1103/physreve.78.015302

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