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arXiv · 1702.08468

Emergence of Multi-Scaling in a Random Force-Stirred Fluid

Victor Yakhot·Diego Donzis
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Abstract

We consider transition to strong turbulence in an infinite fluid stirred by a gaussian random force. The transition is {\bf defined} as a first appearance of anomalous scaling of normalized moments of velocity derivatives (dissipation rates) emerging from the low-Reynolds-number Gaussian background. It is shown that due to multi-scaling, strongly intermittent rare events can be quantitatively described in terms of an infinite number of different "Reynolds numbers" reflecting multitude of anomalous scaling exponents. The theoretically predicted transition disappears at $R_λ\leq 3$. The developed theory, is in a quantitative agreement with the outcome of large-scale numerical simulations.

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Victor Yakhot, Diego Donzis. 2017-02-27. Emergence of Multi-Scaling in a Random Force-Stirred Fluid. https://doi.org/10.1103/physrevlett.119.044501

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