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arXiv · 1204.5150

Vorticity Statistics and the Time Scales of Turbulent Strain

L. Moriconi·R. M. Pereira
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Abstract

Time scales of turbulent strain activity, denoted as the strain persistence times of first and second order, are obtained from time-dependent expectation values and correlation functions of lagrangian rate-of-strain eigenvalues taken in particularly defined statistical ensembles. Taking into account direct numerical simulation data, our approach relies on heuristic closure hypotheses which allow us to establish a connection between the statistics of vorticity and strain. It turns out that softly divergent prefactors correct the usual "1/s" strain time-scale estimate of standard turbulence phenomenology, in a way which is consistent with the phenomenon of vorticity intermittency.

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BibTeXRIS

L. Moriconi, R. M. Pereira. 2013-06-29. Vorticity Statistics and the Time Scales of Turbulent Strain. https://doi.org/10.1103/physreve.88.013005

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