Film transitions of receding contact lines

TL;DR

This paper investigates how the transition from a stationary contact line to a liquid film during plate withdrawal depends on the inclination angle, highlighting the role of capillary waves in this process.

Contribution

It reveals that the bifurcation diagram of the coating transition shifts from discontinuous to continuous as the plate's inclination angle decreases, emphasizing the influence of capillary waves.

Findings

Transition type changes with inclination angle

Capillary waves influence maximum dewetting speed

Flow dynamics affect contact line behavior

Abstract

When a solid plate is withdrawn from a liquid bath, a receding contact line is formed where solid, liquid, and gas meet. Above a critical speed $U_{cr}$, a stationary contact line can no longer exist and the solid will eventually be covered completely by a liquid film. Here we show that the bifurcation diagram of this coating transition changes qualitatively, from discontinuous to continuous, when decreasing the inclination angle of the plate. We show that this effect is governed by the presence of capillary waves, illustrating that the large scale flow strongly effects the maximum speed of dewetting.