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On the properties of steady states in turbulent axisymmetric flows

R. Monchaux·F. Ravelet·B. Dubrulle·A. Chiffaudel·F. Daviaud
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Abstract

We experimentally study the properties of mean and most probable velocity fields in a turbulent von Kármán flow. These fields are found to be described by two families of functions, as predicted by a recent statistical mechanics study of 3D axisymmetric flows. We show that these functions depend on the viscosity and on the forcing. Furthermore, when the Reynolds number is increased, we exhibit a tendency for Beltramization of the flow, i.e. a velocity-vorticity alignment. This result provides a first experimental evidence of nonlinearity depletion in non-homogeneous non-isotropic turbulent flow.

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R. Monchaux, F. Ravelet, B. Dubrulle, A. Chiffaudel, F. Daviaud. 2006-01-25. On the properties of steady states in turbulent axisymmetric flows. https://doi.org/10.1103/physrevlett.96.124502

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