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arXiv · 2208.05611

Asymmetry of velocity increments in turbulence

Katepalli R. Sreenivasan·Kartik P. Iyer·Ashvin Vinodh
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Abstract

We use well-resolved direct numerical simulations of high-Reynolds-number turbulence to study a fundamental statistical property of turbulence -- the asymmetry of velocity increments -- with likely implications on important dynamics. This property, ignored by existing small-scale phenomenological models, manifests most prominently in the non-monotonic trend of velocity increment moments (or structure functions) with the moment order, and in differences between ordinary and absolute structure functions for a given separation distance. We show that high-order structure functions arise nearly entirely from the negative side of the probability density of velocity increments, essentially removing the ambiguity between ordinary and absolute moments, and provide a plausible dynamical interpretation of this result.

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Katepalli R. Sreenivasan, Kartik P. Iyer, Ashvin Vinodh. 2022-08-11. Asymmetry of velocity increments in turbulence. https://doi.org/10.1103/physrevresearch.4.l042002

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