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arXiv · 1009.1051

Energy oscillations and a possible route to chaos in a modified Riga dynamo

Frank Stefani·Agris Gailitis·Gunter Gerbeth
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Abstract

Starting from the present version of the Riga dynamo experiment with its rotating magnetic eigenfield dominated by a single frequency we ask for those modifications of this set-up that would allow for a non-trivial magnetic field behaviour in the saturation regime. Assuming an increased ratio of azimuthal to axial flow velocity, we obtain energy oscillations with a frequency below the eigenfrequency of the magnetic field. These new oscillations are identified as magneto-inertial waves that result from a slight imbalance of Lorentz and inertial forces. Increasing the azimuthal velocity further, or increasing the total magnetic Reynolds number, we find transitions to a chaotic behaviour of the dynamo.

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Frank Stefani, Agris Gailitis, Gunter Gerbeth. 2010-09-06. Energy oscillations and a possible route to chaos in a modified Riga dynamo. https://doi.org/10.1002/asna.201011468

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