Velocity-vorticity correlation and turbulent diffusivity in buoyancy driven fluid dynamics

A. Bershadskii

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arXiv · 1902.04479

Velocity-vorticity correlation and turbulent diffusivity in buoyancy driven fluid dynamics

A. Bershadskii

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Abstract

The velocity-vorticity correlation integral (Chkhetiani invariant) is an invariant of a viscous Karman-Howarth equation. In the tree-dimensional space this invariant can naturally determine a turbulent diffusivity (viscosity). It is shown, using results of direct numerical simulations, that distributed chaos dominated by this integral can provide an adequate description of the turbulent Rayleigh-B\'{e}nard convection, stably stratified turbulence and Rayleigh-Taylor mixing at Prandtl number $Pr \sim 1$.

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A. Bershadskii. 2019-02-12. Velocity-vorticity correlation and turbulent diffusivity in buoyancy driven fluid dynamics. https://arxiv.org/abs/1902.04479

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