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Diffusion as mixing mechanism in granular materials

C. Henrique·G. Batrouni·D. Bideau
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Abstract

We present several numerical results on granular mixtures. In particular, we examine the efficiency of diffusion as a mixing mechanism in these systems. The collisions are inelastic and to compensate the energy loss, we thermalize the grains by adding a random force. Starting with a segregated system, we show that uniform agitation (heating) leads to a uniform mixture of grains of different sizes. We define a characteristic mixing time, $τ_{mix}$, and study theoretically and numerically its dependence on other parameters like the density. We examine a model for bidisperse systems for which we can calculate some physical quantities. We also examine the effect of a temperature gradient and demonstrate the appearance of an expected segregation.

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C. Henrique, G. Batrouni, D. Bideau. 2000-03-22. Diffusion as mixing mechanism in granular materials. https://doi.org/10.1103/physreve.63.011304

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