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Avalanche Mixing of Granular Solids

S. N. Dorogovtsev
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Abstract

Mixing of two fractions of a granular material in a slowly rotating two-dimensional drum is considered. The rotation is around the axis of the upright drum. The drum is filled partially, and mixing occurs only at a free surface of the material. We propose a simple theory of the mixing process which describes a real experiment surprisingly well. A geometrical approach without appealing to ideas of self-organized criticality is used. The dependence of the mixing time on the drum filling is calculated. The mixing time is infinite in the case of the half-filled drum. We describe singular behaviour of the mixing near this critical point.

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S. N. Dorogovtsev. 1997-11-21. Avalanche Mixing of Granular Solids. https://doi.org/10.1209/epl%2Fi1998-00106-9

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