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arXiv · cond-mat/0409114

Shear Excitation of Confined Colloidal Suspensions

Itai Cohen·Thomas G. Mason·David A. Weitz
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Abstract

We show that geometric confinement dramatically affects the shear-induced configurations of dense mono-disperse colloidal suspensions; a new structure emerges, where layers of particles buckle to stack in a more efficient packing. The volume fraction in the shear zone is controlled by a balance between the viscous stresses and the osmotic pressure of a contacting reservoir of unsheared particles. We present a model that accounts for our observations and helps elucidate the complex interplay between particle packing and shear stress for confined suspensions.

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Itai Cohen, Thomas G. Mason, David A. Weitz. 2004-09-06. Shear Excitation of Confined Colloidal Suspensions. https://doi.org/10.1103/physrevlett.93.046001

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