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arXiv · 1202.4645

'Flow & Jam' of frictional athermal systems under shear stress

Raffaele Pastore·Massimo Pica Ciamarra·Antonio Coniglio
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Abstract

We report recent results of molecular dynamics simulations of frictional athermal particles at constant volume fraction and constant applied shear stress, focusing on a range of control parameters where the system first flows, but then jams after a time tjam. On decreasing the volume fraction, the mean jamming time diverges, while its sample fluctuations become so large that the jamming time probability distribution P(tjam) becomes a power-law. We obtain an insight on the origin of this phenomenology focusing on the flowing regime, which is characterized by the presence of a clear correlation between the shear velocity and the mean number of contacts per particles Z, whereby small velocities occur when Z acquires higher values.

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Raffaele Pastore, Massimo Pica Ciamarra, Antonio Coniglio. 2012-02-21. 'Flow & Jam' of frictional athermal systems under shear stress. https://doi.org/10.1080/14786435.2010.540457

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