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arXiv · nlin/0607044

Energy flux fluctuations in a finite volume of turbulent flow

Mahesh Bandi·Walter Goldburg·John Cressman Jr.·Alain Pumir
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Abstract

The flux of turbulent kinetic energy from large to small spatial scales is measured in a small domain B of varying size R. The probability distribution function of the flux is obtained using a time-local version of Kolmogorov's four-fifths law. The measurements, made at a moderate Reynolds number, show frequent events where the flux is backscattered from small to large scales, their frequency increasing as R is decreased. The observations are corroborated by a numerical simulation based on the motion of many particles and on an explicit form of the eddy damping.

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Mahesh Bandi, Walter Goldburg, John Cressman Jr., Alain Pumir. 2006-07-19. Energy flux fluctuations in a finite volume of turbulent flow. https://doi.org/10.1103/physreve.73.026308

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