Implementation of Near-Surface Disjoining Pressure Effect in Continuum Simulations

TL;DR

This paper develops and implements a disjoining pressure model in continuum simulations to accurately capture near-surface molecular interactions affecting water wicking in nanochannels, validated against experimental data.

Contribution

It introduces a novel expression for disjoining pressure based on experimental findings and integrates it into commercial CFD software for nanochannel simulations.

Findings

Simulation results match experimental data closely.

Disjoining pressure significantly influences water wicking in nanochannels.

Method enables better design of nanofluidic systems.

Abstract

An expression of disjoining pressure in a water film, as a function of distance from the surface, is developed from prior experimental findings. The expression is implemented in commercial computational fluid dynamics solver and disjoining pressure effect on water wicking in nanochannels of height varying from 59 nm to 1 micron is simulated. The simulation results are in excellent agreement with experimental data, thus demonstrating and validating that near-surface molecular interactions can be integrated in continuum numerical simulations through the disjoining pressure term. Such an implementation can be used to design and advance nanofluidics-based engineering systems.