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arXiv · 2007.03958

Dispersed fibers change the classical energy budget of turbulence via nonlocal transfer

S. Olivieri·L. Brandt·M. E. Rosti·A. Mazzino
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Abstract

The back-reaction of dispersed rigid fibers to turbulence is analyzed by means of a state-of-the-art fully-coupled immersed boundary method. The following universal scenario is identified: turbulence at large scales looses a consistent part of its kinetic energy (via a Darcy friction term), which partially re-appears at small scales where a new range of energy-containing scales does emerge. Large-scale mixing is thus depleted in favor of a new mixing mechanism arising at the smallest scales. Anchored fibers cause the same back-reaction to turbulence as moving fibers of large inertia. Our results thus provide a link between two apparently separated realms: the one of porous media and the one of suspension dynamics.

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S. Olivieri, L. Brandt, M. E. Rosti, A. Mazzino. 2020-07-08. Dispersed fibers change the classical energy budget of turbulence via nonlocal transfer. https://doi.org/10.1103/physrevlett.125.114501

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