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Test of the Fluctuation Relation in lagrangian turbulence on a free surface

M. M. Bandi·J. R. Cressman Jr.·W. I. Goldburg
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Abstract

The statistics of lagrangian velocity divergence are studied for an assembly of particles in compressible turbulence on a free surface. Under an appropriate definition of entropy, the two-dimensional lagrangian velocity divergence of a particle trajectory represents the local entropy rate, a random variable. The statistics of this rate are shown to be in agreement with the fluctuation relation (FR) over a limited range. The probability distribution functions (PDFs) obtained in this analysis exhibit features different from those observed in previous experimental tests.

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M. M. Bandi, J. R. Cressman Jr., W. I. Goldburg. 2007-03-07. Test of the Fluctuation Relation in lagrangian turbulence on a free surface. https://doi.org/10.1007/s10955-007-9355-4

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