2009/01/01 by Halim Kusumaatmaja, H. Kusumaatmaja, Julia M. Yeomans +1
Engineering · Materials Science · Physics and Astronomy · #Adhesion, Friction, and Surface Interactions #Fluid Dynamics and Heat Transfer #Surface Modification and Superhydrophobicity #cond-mat.mtrl-sci #cond-mat.soft #physics.bio-ph #physics.flu-dyn
paper · pdf · doi:10.1039/b904807c
published as Soft Matter 5, 2704 - 2707 (2009) · 4 pages, 4 figures
openalex publication_date 2009/01/01 · arxiv created 2009/04/26 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
We consider the equilibrium behaviour and dynamics of liquid drops on a superhydrophobic surface patterned with sawtooth ridges or posts. Due to the anisotropic geometry of the surface patterning, the contact line can preferentially depin from one side of the ratchets, leading to a novel, partially suspended, superhydrophobic state. In both this configuration, and the collapsed state, the drops show strong directional contact angle hysteresis as they are pushed across the surface. The easy direction is, however, different for the two states. This observation allows us to interpret recent experiments describing the motion of water drops on butterfly wings.