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Multistability and memory effect in a highly turbulent flow: experimental evidence for a global bifurcation

Florent Ravelet·Louis Marie·Arnaud Chiffaudel·Francois Daviaud
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Abstract

We report an experimental evidence of a global bifurcation on a highly turbulent von Karman flow. The mean flow presents multiple solutions: the canonical symmetric solution becomes marginally unstable towards a flow which breaks the basic symmetry of the driving apparatus even at very large Reynolds number. The global bifurcation between these states is highly subcritical and the system thus keeps a memory of its history. The transition recalls low-dimension dynamical systems transitions and exhibits a very peculiar statistics. We discuss the role of turbulence in two ways: the multiplicity of hydrodynamical solutions and the effect of fluctuations on the nature of transitions.

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Florent Ravelet, Louis Marie, Arnaud Chiffaudel, Francois Daviaud. 2004-09-22. Multistability and memory effect in a highly turbulent flow: experimental evidence for a global bifurcation. https://doi.org/10.1103/physrevlett.93.164501

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