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arXiv · 1503.00988

Mean-field microrheology of a very soft colloidal suspension: inertia induces shear-thickening

Vincent Démery
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Abstract

Colloidal suspensions have a rich rheology and can exhibit shear-thinning as well as shear-thickening. Numerical simulations recently suggested that shear-thickening may be attributed to the inertia of the colloids, besides the hydrodynamic interactions between them. Here, we consider the ideal limit of a dense bath of soft colloids following an underdamped Langevin dynamics. We use a mean-field equation for the colloidal density to get an analytical expression of the drag force felt by a probe pulled at constant velocity through the suspension. Our results show that inertia can indeed induce shear-thickening by allowing density waves to propagate through the suspension.

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Vincent Démery. 2015-03-03. Mean-field microrheology of a very soft colloidal suspension: inertia induces shear-thickening. https://doi.org/10.1103/physreve.91.062301

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