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Analysis of Velocity Derivatives in Turbulence based on Generalized Statistics

N. Arimitsu·T. Arimitsu
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Abstract

A theoretical formula for the probability density function (PDF) of velocity derivatives in a fully developed turbulent flow is derived with the multifractal aspect based on the generalized measures of entropy, i.e., the extensive Renyi entropy or the non-extensive Tsallis entropy, and is used, successfully, to analyze the PDF's observed in the direct numerical simulation (DNS) conducted by Gotoh et al.. The minimum length scale r_d/eta in the longitudinal (transverse) inertial range of the DNS is estimated to be r_d^L/eta = 1.716 (r_d^T/eta = 2.180) in the unit of the Kolmogorov scale eta.

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BibTeXRIS

N. Arimitsu, T. Arimitsu. 2002-07-17. Analysis of Velocity Derivatives in Turbulence based on Generalized Statistics. https://doi.org/10.1209/epl%2Fi2002-00318-5

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