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Giant amplification of interfacially driven transport by hydrodynamic slip: diffusio-osmosis and beyond

Armand Ajdari·Lyderic Bocquet
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Abstract

We demonstrate that "moderate" departures from the no-slip hydrodynamic boundary condition (hydrodynamic slip lengths in the nanometer range) can result in a very large enhancement - up to two orders of magnitude- of most interfacially driven transport phenomena. We study analytically and numerically the case of neutral solute diffusio-osmosis in a slab geometry to account for non-trivial couplings between interfacial structure and hydrodynamic slip. Possible outcomes are fast transport of particles in externally applied or self-generated gradient, and flow enhancement in nano- or micro-fluidic geometries.

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Armand Ajdari, Lyderic Bocquet. 2006-05-22. Giant amplification of interfacially driven transport by hydrodynamic slip: diffusio-osmosis and beyond. https://doi.org/10.1103/physrevlett.96.186102

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