From Equilibrium to Steady State: The Transient Dynamics of Colloidal Liquids under Shear

Abstract

We investigate stresses and particle motion during the start up of flow in a colloidal dispersion close to arrest into a glassy state. A combination of molecular dynamics simulation, mode coupling theory and confocal microscopy experiment is used to investigate the origins of the widely observed stress overshoot and (previously not reported) super-diffusive motion in the transient dynamics. A link between the macro-rheological stress versus strain curves and the microscopic particle motion is established. Negative correlations in the transient auto-correlation function of the potential stresses are found responsible for both phenomena, and arise even for homogeneous flows and almost Gaussian particle displacements.

24 pages, 14 figures, J. Phys.: Condens. Matter, in press

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Cited by in corpus (6)

• Glass Rheology: From mode-coupling theory to a dynamical yield criterion
• A mode coupling theory for Brownian particles in homogeneous steady shear flow
• Nonlinear rheology of colloidal dispersions
• Overshoots in stress strain curves: Colloid experiments and schematic mode coupling theory
• Fluctuation dissipation relations in stationary states of interacting Brownian particles under shear
• Schematic Mode Coupling Theory of Glass Rheology: Single and Double Step Strains