The impact of surface geometry, cavitation, and condensation on wetting transitions: posts and reentrant structures

Panter, J.R.; Kusumaatmaja, H.

Abstract

The fundamental impacts of surface geometry on the stability of wetting states, and the transitions between them are elucidated for square posts and reentrant structures in three dimensions. We identify three principal outcomes of particular importance for future surface design of liquid-repellent surfaces. Firstly, we demonstrate and quantify how capillary condensation and vapour cavitation affect wetting state stabilities. At high contact angles, cavitation is enhanced about wide, closely-spaced square posts, leading to the existence of suspended states without an associated collapsed state. At low contact angles, narrow reentrant pillars suppress condensation and enable the suspension of even highly wetting liquids. Secondly, two distinct collapse mechanisms are observed for 3D reentrant geometries, base contact and pillar contact, which are operative at different pillar heights. As well as morphological differences in the interface of the penetrating liquid, each mechanism is affected differently by changes in the contact angle with the solid. Finally, for highly-wetting liquids, condensates are shown to critically modify the transition pathways in both the base contact and pillar contact modes

Citation

Panter, J., & Kusumaatmaja, H. (2017). The impact of surface geometry, cavitation, and condensation on wetting transitions: posts and reentrant structures. Journal of Physics: Condensed Matter, 29(8), Article 084001. https://doi.org/10.1088/1361-648x/aa5380

• Journal Article Type: Article
• Acceptance Date: Dec 13, 2016
• Online Publication Date: Jan 16, 2017
• Publication Date: Jan 16, 2017
• Deposit Date: Mar 7, 2017
• Publicly Available Date: Jan 16, 2018
• Journal: Journal of Physics: Condensed Matter
• Print ISSN: 0953-8984
• Electronic ISSN: 1361-648X
• Publisher: IOP Publishing
• Peer Reviewed: Peer Reviewed
• Volume: 29
• Issue: 8
• Article Number: 084001
• DOI: https://doi.org/10.1088/1361-648x/aa5380
• Public URL: https://durham-repository.worktribe.com/output/1362102
• Related Public URLs: https://arxiv.org/abs/1609.00287