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Measuring non-extensitivity parameters in a turbulent Couette-Taylor flow

Christian Beck·Gregory S. Lewis·Harry L. Swinney
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Abstract

We investigate probability density functions of velocity differences at different distances r measured in a Couette-Taylor flow for a range of Reynolds numbers Re. There is good agreement with the predictions of a theoretical model based on non-extensive statistical mechanics (where the entropies are non-additive for independent subsystems). We extract the scale-dependent non-extensitivity parameter q(r, Re) from the laboratory data.

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Christian Beck, Gregory S. Lewis, Harry L. Swinney. 2000-10-30. Measuring non-extensitivity parameters in a turbulent Couette-Taylor flow. https://doi.org/10.1103/physreve.63.035303

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