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.
@article{arxiv.1103.4939,
title = {Diffusion of spherical particles in microcavities},
author = {A. Imperio and J. T. Padding and W. J. Briels},
journal= {arXiv preprint arXiv:1103.4939},
year = {2015}
}