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Transport coefficients for electrolytes in arbitrarily shaped nano and micro-fluidic channels

N. A. Mortensen·L. H. Olesen·H. Bruus
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Abstract

We consider laminar flow of incompressible electrolytes in long, straight channels driven by pressure and electro-osmosis. We use a Hilbert space eigenfunction expansion to address the general problem of an arbitrary cross section and obtain general results in linear-response theory for the hydraulic and electrical transport coefficients which satisfy Onsager relations. In the limit of non-overlapping Debye layers the transport coefficients are simply expressed in terms of parameters of the electrolyte as well as the geometrical correction factor for the Hagen-Poiseuille part of the problem. In particular, we consider the limits of thin non-overlapping as well as strongly overlapping Debye layers, respectively, and calculate the corrections to the hydraulic resistance due to electro-hydrodynamic interactions.

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N. A. Mortensen, L. H. Olesen, H. Bruus. 2006-02-20. Transport coefficients for electrolytes in arbitrarily shaped nano and micro-fluidic channels. https://doi.org/10.1088/1367-2630%2F8%2F3%2F037

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