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arXiv · 2007.14145

Friction-controlled entropy-stability competition in granular systems

Xulai Sun·Walter Kob·Raphael Blumenfeld·Hua Tong·Yujie Wang·Jie Zhang
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Abstract

Using cyclic shear to drive a two dimensional granular system, we determine the structural characteristics for different inter-particle friction coefficients. These characteristics are the result of a competition between mechanical stability and entropy, with the latter's effect increasing with friction. We show that a parameter-free maximum-entropy argument alone predicts an exponential cell order distribution, with excellent agreement with the experimental observation. We show that friction only tunes the mean cell order and, consequently, the exponential decay rate and the packing fraction. We further show that cells, which can be very large in such systems, are short-lived, implying that our systems are liquid-like rather than glassy.

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Xulai Sun, Walter Kob, Raphael Blumenfeld, Hua Tong, Yujie Wang, Jie Zhang. 2020-07-28. Friction-controlled entropy-stability competition in granular systems. https://doi.org/10.1103/physrevlett.125.268005

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