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arXiv · 1302.3788

Suppression and emergence of granular segregation under cyclic shear

Matt Harrington·Joost H. Weijs·Wolfgang Losert
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Abstract

While convective flows are implicated in many granular segregation processes, the associated particle-scale rearrangements are not well understood. A three-dimensional bidisperse mixture segregates under steady shear, but the cyclically driven system either remains mixed or segregates slowly. Individual grain motion shows no signs of particle-scale segregation dynamics that precede bulk segregation. Instead, we find that the transition from non-segregating to segregating flow is accompanied by significantly less reversible particle trajectories, and the emergence of a convective flow field.

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Matt Harrington, Joost H. Weijs, Wolfgang Losert. 2013-02-15. Suppression and emergence of granular segregation under cyclic shear. https://doi.org/10.1103/physrevlett.111.078001

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