Spreading in narrow channels

TL;DR

This paper investigates fluid film spreading in narrow channels using a lattice model, revealing diffusive behavior with a diffusion coefficient influenced by density, supported by kinetic Monte Carlo simulations and continuum analysis.

Contribution

It introduces a lattice model for thin fluid films in narrow channels with inert walls, analyzing diffusion properties through simulations and continuum limits.

Findings

Diffusive spreading observed in the model

Diffusion coefficient depends on density

Lower bound set by free 1D diffusion

Abstract

We study a lattice model for the spreading of fluid films, which are a few molecular layers thick, in narrow channels with inert lateral walls. We focus on systems connected to two particle reservoirs at different chemical potentials, considering an attractive substrate potential at the bottom, confining side walls, and hard-core repulsive fluid-fluid interactions. Using kinetic Monte Carlo simulations we find a diffusive behavior. The corresponding diffusion coefficient depends on the density and is bounded from below by the free one-dimensional diffusion coefficient, valid for an inert bottom wall. These numerical results are rationalized within the corresponding continuum limit.