Schematic models for dynamic yielding of sheared colloidal glasses

Matthias Fuchs; Michael E. Cates

doi:10.1039/b205629a

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arXiv · cond-mat/0207530

Schematic models for dynamic yielding of sheared colloidal glasses

Matthias Fuchs·Michael E. Cates

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Abstract

The nonlinear rheological properties of dense suspensions are discussed within simplified models, suggested by a recent first principles approach to the model of Brownian particles in a constant-velocity-gradient solvent flow. Shear thinning of colloidal fluids and dynamical yielding of colloidal glasses arise from a competition between a slowing down of structural relaxation, because of particle interactions, and enhanced decorrelation of fluctuations, caused by the shear advection of density fluctuations. A mode coupling approach is developed to explore the shear-induced suppression of particle caging and the resulting speed-up of the structural relaxation.

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Matthias Fuchs, Michael E. Cates. 2002-09-04. Schematic models for dynamic yielding of sheared colloidal glasses. https://doi.org/10.1039/b205629a

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