A new article has been published in Physical Review Fluids, entitled: Introducing nonlocal solid-fluid interactions into the Navier-Stokes-Korteweg model
Nanoscale fluid morphologies, including adsorbed layers and thin liquid films, are strongly influenced by intermolecular forces. In the article, we present a continuum model for nanoscale wetting that incorporates a nonlocal, Lennard-Jones-like solid-fluid interaction potential into the Navier-Stokes-Korteweg framework. This approach enables the study of nanoscale fluid phenomena such as vapor adsorption and thin film dynamics with a continuum description. Our results indicate that the added potential compresses fluid near the solid substrate, forming adsorbed layers in the vapor regime and modifying the density within liquid films. In thin liquid films, purely attractive interactions initially compress the film, leading to transient rearrangements in density gradients before stabilizing with a higher near-wall density. Under thermally driven phase change, the solid-fluid potential modulates liquid-vapor phase change by altering local equilibrium conditions. Near-wall compression inhibits late-time evaporation, stabilizing the film at a finite thickness. In condensation, the film thickens similarly to the no-potential case initially, but then gradually stabilizes as the near-wall region approaches equilibrium. Our analyses show that solid-fluid interaction forces control nanoscale phase change and liquid-vapor coexistence, providing a continuum description that complements molecular and classical continuum methods. Our key contribution is to treat the wall-fluid interaction as a nonlocal bulk potential within the NSK-DGT free energy, which reorganizes near-wall density and modulates interfacial mass transfer while preserving thermodynamic consistency.
The main man behind the article is Dr. Vitor Cunha, who is now a postdoc in the group.
