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arXiv · 1010.5368

Statistical mechanics and large-scale velocity fluctuations of turbulence

H. Mouri·A. Hori·Y. Kawashima·K. Hashimoto
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Abstract

Turbulence exhibits significant velocity fluctuations even if the scale is much larger than the scale of the energy supply. Since any spatial correlation is negligible, these large-scale fluctuations have many degrees of freedom and are thereby analogous to thermal fluctuations studied in the statistical mechanics. By using this analogy, we describe the large-scale fluctuations of turbulence in a formalism that has the same mathematical structure as used for canonical ensembles in the statistical mechanics. The formalism yields a universal law for the energy distribution of the fluctuations, which is confirmed with experiments of a variety of turbulent flows. Thus, through the large-scale fluctuations, turbulence is related to the statistical mechanics.

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BibTeXRIS

H. Mouri, A. Hori, Y. Kawashima, K. Hashimoto. 2011-11-19. Statistical mechanics and large-scale velocity fluctuations of turbulence. https://doi.org/10.1063/1.3667268

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