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Rate-dependent slip boundary conditions for simple fluids

Nikolai V. Priezjev
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Abstract

The dynamic behavior of the slip length in a fluid flow confined between atomically smooth surfaces is investigated using molecular dynamics simulations. At weak wall-fluid interactions, the slip length increases nonlinearly with the shear rate provided that the liquid/solid interface forms incommensurable structures. A gradual transition to the linear rate-dependence is observed upon increasing the wall-fluid interaction. We found that the slip length can be well described by a function of a single variable that in turn depends on the in-plane structure factor, contact density and temperature of the first fluid layer near the solid wall. Extensive simulations show that this formula is valid in a wide range of shear rates and wall-fluid interactions.

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Nikolai V. Priezjev. 2007-02-20. Rate-dependent slip boundary conditions for simple fluids. https://doi.org/10.1103/physreve.75.051605

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