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arXiv · 2105.00977

Jamming of Bidisperse Frictional Spheres

Ishan Srivastava·Scott A. Roberts·Joel T. Clemmer·Leonardo E. Silbert·Jeremy B. Lechman·Gary S. Grest
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Abstract

By generalizing a geometric argument for frictionless spheres, a model is proposed for the jamming density $\phi_J$ of mechanically stable packings of bidisperse, frictional spheres. The monodisperse, $\mu_s$-dependent jamming density $\phi_J^{\mathrm{mono}}(\mu_s)$ is the only input required in the model, where $\mu_s$ is the coefficient of friction. The predictions of the model are validated by robust estimates of $\phi_J$ obtained from computer simulations of up to $10^7$ particles for a wide range of $\mu_s$, and size ratios up to 40:1. Although $\phi_J$ varies nonmonotonically with the volume fraction of small spheres $f^s$ for all $\mu_s$, its maximum value $\phi_{J,\mathrm{max}}$ at an optimal $f^{s}_{\mathrm{max}}$ are both $\mu_s$-dependent. The optimal $f^{s}_{\mathrm{max}}$ is characterized by a sharp transition in the fraction of small rattler particles.

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Ishan Srivastava, Scott A. Roberts, Joel T. Clemmer, Leonardo E. Silbert, Jeremy B. Lechman, Gary S. Grest. 2021-05-03. Jamming of Bidisperse Frictional Spheres. https://doi.org/10.1103/physrevresearch.3.l032042

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