Kinematic α tensors and dynamo mechanisms in a von Kármán swirling flow.

Phys Rev Lett

Arts et Metiers ParisTech, DynFluid, 151 boulevard de l'Hôpital, 75013 Paris, France.

Published: July 2012

We provide experimental and numerical evidence of in-blades vortices in the von Kármán swirling flow. We estimate the associated kinematic α-effect tensor and show that it is compatible with recent models of the von Kármán sodium (VKS) dynamo. We further show that depending on the relative frequency of the two impellers, the dominant dynamo mechanism may switch from α2 to α - Ω dynamo. We discuss some implications of these results for VKS experiments.

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http://dx.doi.org/10.1103/PhysRevLett.109.024503DOI Listing

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