Soft Wetting Ridge Rotation in Sessile Droplets and Capillary Bridges.

ABSTRACT: We investigate the deformation of soft solid layers in the presence of sessile droplets or capillary bridges. Unlike models that assume Young's law governs the contact angle, we incorporate the surface tension balance at the contact line to analyze the rotation of the wetting ridge and the corresponding change in the contact angle. Our findings reveal that the rotation direction of the wetting ridge aligns with the sign of the Laplace pressure. Interestingly, although a softer solid layer typically decreases the contact angle for sessile droplets, a negative Laplace pressure in a hydrophilic capillary bridge pulls the solid-liquid interface, leading to an increased contact angle. A hydrophilic capillary bridge would be expected to move from thicker regions of a soft layer to thinner areas,

SUBMITTER: Zheng BX 

PROVIDER: S-EPMC11841037 | biostudies-literature | 2025 Feb

REPOSITORIES: biostudies-literature