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arXiv · 1103.4939

Diffusion of spherical particles in microcavities

A. Imperio·J. T. Padding·W. J. Briels
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Abstract

The diffusive motion of a colloidal particle trapped inside a small cavity filled with fluid is reduced by hydrodynamic interactions with the confining walls. In this work, we study these wall effects on a spherical particle entrapped in a closed cylinder. We calculate the diffusion coefficient along the radial, azimuthal and axial direction for different particle positions. At all locations the diffusion is smaller than in a bulk fluid and it becomes anisotropic near the container's walls. We present a simple model which reasonably well desribes the simulation results for the given dimensions of the cylinder, which are taken from recent experimental work.

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A. Imperio, J. T. Padding, W. J. Briels. 2011-03-25. Diffusion of spherical particles in microcavities. https://doi.org/10.1063/1.3578186

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