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arXiv · 1407.1213

Anomalous diffusion for inertial particles under gravity in parallel flows

Marco Martins Afonso
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Abstract

We investigate the bounds between normal or anomalous effective diffusion for inertial particles transported by parallel flows. The infrared behavior of the fluid kinetic-energy spectrum, i.e. the possible presence of long-range spatio-temporal correlations, is modeled as a power law by means of two parameters, and the problem is studied as a function of these latter. Our results, obtained in the limit of weak relative inertia, extend well-known results for tracers and apply to particles of any mass density, subject to gravity and Brownian diffusion. We consider both steady and time-dependent flows, and cases of both vanishing and finite particle sedimentation.

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Marco Martins Afonso. 2014-07-04. Anomalous diffusion for inertial particles under gravity in parallel flows. https://doi.org/10.1103/physreve.89.063021

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