The vicinity of an equilibrium three-phase contact line using density-functional theory: density profiles normal to the fluid interface

ABSTRACT

The paper by Nold et al. [Phys. Fluids 26 (7), 072001 (2014)] examined density profiles and the micro-scale structure of an equilibrium three-phase (liquid–vapour–solid) contact line in the immediate vicinity of the wall using elements from the statistical mechanics of classical fluids, namely density-functional theory. The present research note, building on the above work, further contributes to our understanding of the nanoscale structure of a contact line by quantifying the strong dependence of the liquid–vapour density profile on the normal distance to the interface, when compared to the dependence on the vertical distance to the substrate. A recent study by Benet et al. [J. Phys. Chem. C 118 (38), 22079 (2014)] has shown that this could explain the emergence of a film-height-dependent surface tension close to the wall, with implications for the Frumkin–Derjaguin theory.

GRAPHICAL ABSTRACT

KEYWORDS:

• Micro/nanoscale phenomena
• non-continuum effects
• density-functional theory
• contact lines
• film-height-dependent surface tension

Acknowledgements

LGM would like to thank A. Archer and D.N. Sibley for an enjoyable stay at Loughborough University.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

LGM acknowledges funding from the 'Programa Estatal de Promoción del Talento y su Empleabilidaden I+D+i' by the Spanish Ministerio de Educación, Cultura y Deporte (Plan Estatal de Investigación Científica y Técnica y de Innovación 2013–2016). AN, DNS, BDG and SK acknowledge financial support from Imperial College (IC) through a DTG International Studentship, from the Engineering and Physical Sciences Research Council (EPSRC) of the UK through Grant Nos. EP/L027186, EP/L025159 and EP/L020564 and from the FP7 Ideas: European Research Council (ERC) through Advanced Grant No. 247031.