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PDF of Velocity Fluctuation in Turbulence by a Statistics based on Generalized Entropy

Toshihico Arimitsu·Naoko Arimitsu
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Abstract

An analytical formula for the probability density function (PDF) of the velocity fluctuation in fully-developed turbulence is derived, non-perturbatively, by assuming that its underlying statistics is the one based on the generalized measures of entropy, the Rényi entropy or the Tsallis-Havrda-Charvat (THC) entropy. The parameters appeared in the PDF, including the index $q$ which appears in the measures of the Rényi entropy or of the THC entropy are determined self-consistently with the help of the observed value $μ$ of the intermittency exponent. The derived PDF explains quite well the experimentally observed density functions.

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Toshihico Arimitsu, Naoko Arimitsu. 2001-11-02. PDF of Velocity Fluctuation in Turbulence by a Statistics based on Generalized Entropy. https://doi.org/10.1016/s0378-4371(01)00665-3

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