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arXiv · nlin/0208004

Local 4/5-Law and Energy Dissipation Anomaly in Turbulence

Abstract

A strong local form of the ``4/3-law'' in turbulent flow has been proved recently by Duchon and Robert for a triple moment of velocity increments averaged over both a bounded spacetime region and separation vector directions, and for energy dissipation averaged over the same spacetime region. Under precisely stated hypotheses, the two are proved to be proportional, by a constant 4/3, and to appear as a nonnegative defect measure in the local energy balance of singular (distributional) solutions of the incompressible Euler equations. Here we prove that the energy defect measure can be represented also by a triple moment of purely longitudinal velocity increments and by a mixed moment with one longitudinal and two tranverse velocity increments. Thus, we prove that the traditional 4/5- and 4/15-laws of Kolmogorov hold in the same local sense as demonstrated for the 4/3-law by Duchon-Robert.

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BibTeXRIS

Gregory L. Eyink. 2002-08-05. Local 4/5-Law and Energy Dissipation Anomaly in Turbulence. https://doi.org/10.1088/0951-7715%2F16%2F1%2F309

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