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arXiv · 2107.11855

Coherence of velocity fluctuations in turbulent flows

G. Prabhudesai·S. Perrard·F. Pétrélis·S. Fauve
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Abstract

We investigate the spatio-temporal quantity of coherence for turbulent velocity fluctuations at spatial distances of the order or larger than the integral length scale $l_{0}$. Using controlled laboratory experiments, an exponential decay as a function of distance is observed with a decay rate which depends on the flow properties. The same law is observed in two different flows indicating that it can be a generic property of turbulent flows.

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G. Prabhudesai, S. Perrard, F. Pétrélis, S. Fauve. 2021-07-25. Coherence of velocity fluctuations in turbulent flows. https://doi.org/10.1103/physrevlett.128.014501

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