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Updated: Apr 27, 2026

A Modeling and Simulation Method for Preliminary Design of an Electro-Variable Displacement Pump
Published on: June 1, 2022
Dynamo efficiency controlled by hydrodynamic bistability
Sophie Miralles1, Johann Herault, Johann Herault
1Laboratoire de Physique, École Normale Supérieure de Lyon, CNRS & Université de Lyon, 46 allée d'Italie, 69364 Lyon Cedex 07, France.
Abstract:
Hydrodynamic and magnetic behaviors in a modified experimental setup of the von Kármán sodium flow-where one disk has been replaced by a propeller-are investigated. When the rotation frequencies of the disk and the propeller are different, we show that the fully turbulent hydrodynamic flow undergoes a global bifurcation between two configurations. The bistability of these flow configurations is associated with the dynamics of the central shear layer. The bistable flows are shown to have different dynamo efficiencies; thus for a given rotation rate of the soft-iron disk, two distinct magnetic behaviors are observed depending on the flow configuration. The hydrodynamic transition controls the magnetic field behavior, and bifurcations between high and low magnetic field branches are investigated.
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