Avalanche mixing of granular solids in a rotating 2D drum: diffusion and fractionality

S. N. Dorogovtsev

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arXiv · cond-mat/9807386

Avalanche mixing of granular solids in a rotating 2D drum: diffusion and fractionality

S. N. Dorogovtsev

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Abstract

The dynamics of the avalanche mixing in a slowly rotated 2D upright drum is studied in the situation where the difference $δ$ between the angle of marginal stability and the angle of repose of the granular material is finite. An analytical solution of the problem is found for a half filled drum, that is the most interesting case. The mixing is described by a simple linear difference equation. We show that the mixing looks like linear diffusion of fractions under consideration with the diffusion coefficient vanishing when $δ$ is an integer part of $π$. The characteristic mixing time tends to infinity in these points. A full dependence of the mixing time on $δ$ is calculated and predictions for an experiment are made.

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S. N. Dorogovtsev. 1998-08-03. Avalanche mixing of granular solids in a rotating 2D drum: diffusion and fractionality. https://arxiv.org/abs/cond-mat/9807386

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