A numerical approach for the direct computation of flows including fluid-solid interaction: modeling contact angle, film rupture, and dewetting

TL;DR

This paper introduces an efficient numerical method for simulating fluid-solid interactions in fluid flows, enabling accurate modeling of contact angles, film rupture, and dewetting phenomena with improved computational performance.

Contribution

The authors develop a new computational approach that enhances efficiency and accuracy in simulating fluid-solid interactions, surpassing previous methods in performance.

Findings

Accurate computation of droplet contact angles at equilibrium.

Analysis of film instability and rupture influenced by fluid-solid interactions.

Observation of nonlinear effects leading to larger characteristic length scales.

Abstract

In this paper, we present a computationally efficient method for including fluid-solid interactions into direct numerical simulations of the Navier-Stokes equations. This method is found to be as powerful as our earlier formulation [J. Comp. Phys., vol. 249: 243 (2015)], while outperforming the earlier method in terms of computational efficiency. The performance and efficacy of the presented method are demonstrated by computing contact angles of droplets at equilibrium. Furthermore, we study the instability of films due to destabilizing fluid-solid interactions, and discuss the influence of contact angle and inertial effects on film breakup. In particular, direct simulation results show an increase in the final characteristic length scales when compared to the predictions of a linear stability analysis, suggesting significant influence of nonlinear effects. Our results also show that emerging length scales differ, depending on a number of physical dimensions considered.