Turbulent Diffusion-Cascade Interaction

Ernesto Fuentes Noriega; John Christos Vassilicos

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arXiv · 2601.04847

Turbulent Diffusion-Cascade Interaction

Ernesto Fuentes Noriega·John Christos Vassilicos

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Abstract

In the decay region around the centreline of three qualitatively different turbulent plane wakes, the turbulence is non-homogeneous and two-point turbulent diffusion counteracts the turbulence cascade all the way down to scales smaller than the Taylor length. It is found that the sum of the inter-space transfer rate and the horizontal part of the inter-scale transfer rate of horizontal two-point turbulent kinetic energy is approximately proportional to the turbulence dissipation rate in the inertial range with a constant of proportionality between $-0.6$ and $-1$ depending on wake and location within the wake, except at the near-field edge of the decay region.

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Ernesto Fuentes Noriega, John Christos Vassilicos. 2026-01-08. Turbulent Diffusion-Cascade Interaction. https://arxiv.org/abs/2601.04847

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