Universal molecular-kinetic scaling relation for slip of a simple fluid at a solid boundary

© 2019 American Physical Society. Using the observation that slip in simple fluids at low and moderate shear rates is a thermally activated process driven by the shear stress in the fluid close to the solid boundary, we develop a molecular-kinetic model for simple fluid slip at solid boundaries. The...

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Bibliographic Details
Main Authors: Wang, Gerald J, Hadjiconstantinou, Nicolas G
Other Authors: Massachusetts Institute of Technology. Department of Mechanical Engineering
Format: Article
Language:English
Published: American Physical Society (APS) 2021
Online Access:https://hdl.handle.net/1721.1/136511
Description
Summary:© 2019 American Physical Society. Using the observation that slip in simple fluids at low and moderate shear rates is a thermally activated process driven by the shear stress in the fluid close to the solid boundary, we develop a molecular-kinetic model for simple fluid slip at solid boundaries. The proposed model, which is in the form of a universal scaling relation that connects slip and shear rate, reduces to the well-known Navier slip condition under low shear conditions, providing a direct connection between molecular parameters and the slip length. Molecular-dynamics simulations are in very good agreement with the predicted dependence of slip on system parameters, including the temperature and fluid-solid interaction strength. Connections between our model and previous work, as well as simulation and experimental results, are explored and discussed.