Skip to Main content Skip to Navigation
Journal articles

Shear force measurement of the hydrodynamic wall position in molecular dynamics

Abstract : Flows in nanofluidic systems are strongly affected by liquid-solid slip, which is quantified by the slip length and by the position where the slip boundary condition applies. Here, we show that the viscosity, slip length, and hydrodynamic wall position (HWP) can be accurately determined from a single molecular dynamics (MD) simulation of a Poiseuille flow, after identifying a relation between the HWP and the wall shear stress in that configuration. From this relation, we deduce that in gravity-driven flows, the HWP identifies with the Gibbs dividing plane of the liquid-vacuum density profile. Simulations of a generic Lennard-Jones liquid confined between parallel frozen walls show that the HWP for a pressure-driven flow is also close to the Gibbs dividing plane (measured at equilibrium), which therefore provides an inexpensive estimate of the HWP, going beyond the common practice of assuming a given position for the hydrodynamic wall. For instance, we show that the HWP depends on the wettability of the surface, an effect usually neglected in MD studies of liquid-solid slip. Overall, the method introduced in this article is simple, fast, and accurate and could be applied to a large variety of systems of interest for nanofluidic applications.
Document type :
Journal articles
Complete list of metadata
Contributor : Armelle VIDAL Connect in order to contact the contributor
Submitted on : Thursday, December 10, 2020 - 9:23:36 AM
Last modification on : Sunday, June 26, 2022 - 3:00:32 AM
Long-term archiving on: : Thursday, March 11, 2021 - 6:43:09 PM


Publisher files allowed on an open archive




Cecilia Herrero, Takeshi Omori, yasutaka yamaguchi, Laurent Joly. Shear force measurement of the hydrodynamic wall position in molecular dynamics. Journal of Chemical Physics, American Institute of Physics, 2019, 151 (4), pp.041103. ⟨10.1063/1.5111966⟩. ⟨hal-02367716⟩



Record views


Files downloads