Identifying the multifractal set on which energy dissipates in a turbulent Navier-Stokes fluid

John D. Gibbon

doi:10.1016/j.physd.2023.133654

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arXiv · 2212.10860

Identifying the multifractal set on which energy dissipates in a turbulent Navier-Stokes fluid

John D. Gibbon

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Abstract

The rich multifractal properties of fluid turbulence illustrated by the work of Parisi and Frisch are related explicitly to Leray's weak solutions of the three-dimensional Navier-Stokes equations. Directly from this correspondence it is found that the set on which energy dissipates, $\mathbb{F}_{m}$, has a range of dimensions $\Dim=3/m$ ($1 \leq m \leq \infty$), and a corresponding range of sub-Kolmogorov dissipation inverse length scales $L\eta_{m}^{-1} \leq Re^{3/(1+\Dim)}$ spanning $Re^{3/4}$ to $Re^{3}$. Correspondingly, the multifractal model scaling parameter $h$, must obey $h \geq h_{min}$ with $-\twothirds \leq h_{min} \leq \third$.

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John D. Gibbon. 2022-12-21. Identifying the multifractal set on which energy dissipates in a turbulent Navier-Stokes fluid. https://doi.org/10.1016/j.physd.2023.133654

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