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arXiv · 0712.3592

Tunable-slip boundaries for coarse-grained simulations of fluid flow

Jens Smiatek·Michael P. Allen·Friederike Schmid
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Abstract

On the micro- and nanoscale, classical hydrodynamic boundary conditions such as the no-slip condition no longer apply. Instead, the flow profiles exhibit ``slip`` at the surface, which is characterized by a finite slip length (partial slip). We present a new, systematic way of implementing partial-slip boundary conditions with arbitrary slip length in coarse-grained computer simulations. The main idea is to represent the complex microscopic interface structure by a spatially varying effective viscous force. An analytical equation for the resulting slip length can be derived for planar and for curved surfaces. The comparison with computer simulations of a DPD (dissipative particle dynamics) fluid shows that this expression is valid from full-slip to no-slip.

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Jens Smiatek, Michael P. Allen, Friederike Schmid. 2008-03-20. Tunable-slip boundaries for coarse-grained simulations of fluid flow. https://doi.org/10.1140/epje%2Fi2007-10311-4

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