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Diffusion in pores and its dependence on boundary conditions

Anthony Saugey·Laurent Joly·Christophe Ybert·Jean-Louis Barrat·Lyderic Bocquet
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Abstract

We study the influence of the boundary conditions at the solid liquid interface on diffusion in a confined fluid. Using an hydrodynamic approach, we compute numerical estimates for the diffusion of a particle confined between two planes. Partial slip is shown to significantly influence the diffusion coefficient near a wall. Analytical expressions are derived in the low and high confinement limits, and are in good agreement with numerical results. These calculations indicate that diffusion of tagged particles could be used as a sensitive probe of the solid-liquid boundary conditions.

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Anthony Saugey, Laurent Joly, Christophe Ybert, Jean-Louis Barrat, Lyderic Bocquet. 2005-06-27. Diffusion in pores and its dependence on boundary conditions. https://doi.org/10.1088/0953-8984%2F17%2F49%2F005

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