title: Mean-field microrheology of a very soft colloidal suspension: Inertia induces shear thickening.
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.
authors.affiliation: Department of Physics, University of Massachusetts, Amherst, Massachusetts 01003, USA and Laboratoire de Physico-Chimie Théorique, UMR CNRS Gulliver 7083, ESPCI, Paris, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Démery