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arXiv · 1307.2133

Shear thickening in granular suspensions: inter-particle friction and dynamically correlated clusters

Claus Heussinger
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Abstract

We consider the shear rheology of concentrated suspensions of non-Brownian frictional particles. The key result of our study is the emergence of a pronounced shear-thickening regime, where frictionless particles would normally undergo shear-thinning. We clarify that shear thickening in our simulations is due to enhanced energy dissipation via frictional inter-particle forces. Moreover, we evidence the formation of dynamically correlated particle-clusters of size $ξ$, which contribute to shear thickening via an increase in \emph{viscous} dissipation. A scaling argument gives $η\sim ξ^2$, which is in very good agreement with the data.

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Claus Heussinger. 2013-11-21. Shear thickening in granular suspensions: inter-particle friction and dynamically correlated clusters. https://doi.org/10.1103/physreve.88.050201

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