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arXiv · 2109.08761

Thermal Fluctuations in the Dissipation Range of Homogeneous Isotropic Turbulence

John B. Bell·Andrew Nonaka·Alejandro L. Garcia·Gregory Eyink
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Abstract

Using fluctuating hydrodynamics we investigate the effect of thermal fluctuations in the dissipation range of homogeneous, isotropic turbulence. Simulations confirm theoretical predictions that the energy spectrum is dominated by these fluctuations at length scales comparable to the Kolmogorov length. We also find that the extreme intermittency in the far-dissipation range predicted by Kraichnan is replaced by Gaussian thermal equipartition.

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John B. Bell, Andrew Nonaka, Alejandro L. Garcia, Gregory Eyink. 2021-09-17. Thermal Fluctuations in the Dissipation Range of Homogeneous Isotropic Turbulence. https://doi.org/10.1017/jfm.2022.188

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