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arXiv · 0806.4582

Velocity oscillations in confined channel flows of concentrated colloidal suspensions

Lucio Isa·Rut Besseling·Alexander N. Morozov·Wilson C. K. Poon
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Abstract

We study the pressure-driven flow of concentrated colloids confined in glass micro-channels at the single particle level using fast confocal microscopy. For channel to particle size ratios $a/\bar{D} \lesssim 30$, the flow rate of the suspended particles shows fluctuations. These turn into regular oscillations for higher confinements ($a/\bar{D} \simeq 20$). We present evidence to link these oscillations with the relative flow of solvent and particles (permeation) and the effect of confinement on shear thickening.

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Lucio Isa, Rut Besseling, Alexander N. Morozov, Wilson C. K. Poon. 2008-06-27. Velocity oscillations in confined channel flows of concentrated colloidal suspensions. https://doi.org/10.1103/physrevlett.102.058302

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