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arXiv · 1607.07289

Angular dynamics of small crystals in viscous flow

J. Fries·J. Einarsson·B. Mehlig
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Abstract

The angular dynamics of a very small ellipsoidal particle in a viscous flow decouples from its translational dynamics, and the particle angular velocity is given by Jeffery's theory. It is known that cuboid particles share these properties. In the literature a special case is most frequently discussed, namely that of axisymmetric particles with a continuous rotation symmetry. Here we compute the angular dynamics of crystals that possess a discrete rotation symmetry and certain mirror symmetries, but that do not have a continuous rotation symmetry. We give examples of such particles that nevertheless obey Jeffery's theory. But there are other examples where the angular dynamics is determined by a more general equation of motion.

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J. Fries, J. Einarsson, B. Mehlig. 2016-07-25. Angular dynamics of small crystals in viscous flow. https://doi.org/10.1103/physrevfluids.2.014302

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