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Large-Scale Coherence and Law of Decay of Two-Dimensional Turbulence

Victor Yakhot·John Wanderer
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Abstract

At the short times, the enstrophy $Ω$ of a two-dimensional flow, generated by a random Gaussian initial condition decays as $Ω(t)\propto t^{-γ}$ with $γ\approx 0.7$. After that, the flow undergoes transition to a different state characterized by the magnitude of the decay exponent $γ\approx 0.4$ (Yakhot, Wanderer, Phys.Rev.Lett.{\bf 93}, 154502 \~(2004)). It is shown that the very existence of this transition and various characteristics of evolving flow crucially depend upon phase correlation between the large-scale modes containing only a few percent of total enstrophy.

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Victor Yakhot, John Wanderer. 2004-11-09. Large-Scale Coherence and Law of Decay of Two-Dimensional Turbulence. https://arxiv.org/abs/nlin/0411019

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