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arXiv · 1105.2594

Flow-induced shear instabilities of cohesive granulates

Ilenia Battiato·Jürgen Vollmer
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Abstract

In this work we use a multi-scale framework to calculate the fluidization threshold of three-dimensional cohesive granulates under shear forces exerted by a creeping flow. A continuum model of flow through porous media provides an analytical expression for the average drag force on a single grain. The balance equation for the forces and a force propagation model are then used to investigate the effects of porosity and packing structure on the stability of the pile. We obtain a closed-form expression for the instability threshold of a regular packing of mono-disperse frictionless cohesive spherical grains in a planar fracture. Our result quantifies the compound effect of structural (packing orientation and porosity) and dynamical properties of the system on its stability.

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Ilenia Battiato, Jürgen Vollmer. 2013-07-26. Flow-induced shear instabilities of cohesive granulates. https://doi.org/10.1103/physreve.86.031301

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