Intermittent magnetic field excitation by a turbulent flow of liquid sodium

Abstract

The magnetic field measured in the Madison Dynamo Experiment shows intermittent periods of growth when an axial magnetic field is applied. The geometry of the intermittent field is consistent with the fastest growing magnetic eigenmode predicted by kinematic dynamo theory using a laminar model of the mean flow. Though the eigenmodes of the mean flow are decaying, it is postulated that turbulent fluctuations of the velocity field change the flow geometry such that the eigenmode growth rate is temporarily positive. Therefore, it is expected that a characteristic of the onset of a turbulent dynamo is magnetic intermittency.

arXiv comment5 pages, 7 figures

References in corpus (4)

• Detection of a flow induced magnetic field eigenmode in the Riga dynamo facility
• Magnetic Field Saturation in the Riga Dynamo Experiment
• Observation of a Turbulence-Induced Large Scale Magnetic Field
• Measurements of the magnetic field induced by a turbulent flow of liquid metal

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