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arXiv · 0911.4635

Flow-induced Agitations Create a Granular Fluid

Kiri Nichol·Alexey Zanin·Renaud Bastien·Elie Wandersman·Martin van Hecke
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Abstract

We fluidize a granular medium through localized stirring and probe the mechanical response of quiescent regions far away from the main flow. In these regions the material behaves like a liquid: high-density probes sink, low-density probes float at the depth given by Archimedes' law, and drag forces on moving probes scale linearly with the velocity. The fluid-like character of the material is set by agitations generated in the stirred region, suggesting a non-local rheology: the relation between applied stress and observed strain rate in one location depends on the strain rate in another location.

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Kiri Nichol, Alexey Zanin, Renaud Bastien, Elie Wandersman, Martin van Hecke. 2009-11-24. Flow-induced Agitations Create a Granular Fluid. https://doi.org/10.1103/physrevlett.104.078302

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