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Metastability of a granular surface in a spinning bucket

Chuck Yeung
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Abstract

The surface shape of a spinning bucket of granular material is studied using a continuum model of surface flow developed by Bouchaud et al. and Mehta et al. An experimentally observed central subcritical region is reproduced by the model. The subcritical region occurs when a metastable surface becomes unstable via a nonlinear instability mechanism. The nonlinear instability mechanism destabilizes the surface in large systems while a linear instability mechanism is relevant for smaller systems. The range of angles in which the granular surface is metastable vanishes with increasing system size.

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Chuck Yeung. 1998-03-10. Metastability of a granular surface in a spinning bucket. https://doi.org/10.1103/physreve.57.4528

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