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arXiv · 0910.2623

Diffusion and Velocity Auto-Correlation in Shearing Granular Media

Peter Olsson
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Abstract

We perform numerical simulations to examine particle diffusion at steady shear in a model granular material in two dimensions at the jamming density and zero temperature. We confirm findings by others that the diffusion constant depends on shear rate as $D\sim\dot\gamma^{q_D}$ with $q_D<1$, and set out to determine a relation between $q_D$ and other exponents that characterize the jamming transition. We then examine the the velocity auto-correlation function, note that it is governed by two processes with different time scales, and identify a new fundamental exponent, $\lambda$, that characterizes an algebraic decay of correlations with time.

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Peter Olsson. 2009-10-14. Diffusion and Velocity Auto-Correlation in Shearing Granular Media. https://doi.org/10.1103/physreve.81.040301

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