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arXiv · 1702.07516

Statistical model for the orientation of non-spherical particles settling in turbulence

K. Gustavsson·J. Jucha·A. Naso·E. Lévêque·A. Pumir·B. Mehlig
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Abstract

The orientation of small anisotropic particles settling in a turbulent fluid determines some essential properties of the suspension. We show that the orientation distribution of small heavy spheroids settling through turbulence can be accurately predicted by a simple Gaussian statistical model that takes into account particle inertia and provides a quantitative understanding of the orientation distribution on the problem parameters when fluid inertia is negligible. Our results open the way to a parameterisation of the distribution of ice-crystals in clouds, and potentially leads to an improved understanding of radiation reflection, or particle aggregation through collisions in clouds.

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K. Gustavsson, J. Jucha, A. Naso, E. Lévêque, A. Pumir, B. Mehlig. 2017-07-27. Statistical model for the orientation of non-spherical particles settling in turbulence. https://doi.org/10.1103/physrevlett.119.254501

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