2018/09/30 by Alexander T. Bradley, Finn Box, Ian Hewitt +2 · 49 citations
Engineering · Materials Science · Physics and Astronomy · #Composite material #Electrohydrodynamics and Fluid Dynamics #Electrowetting and Microfluidic Technologies #Materials science #Nanotechnology #Surface Modification and Superhydrophobicity #Wetting #cond-mat.soft #physics.flu-dyn
paper · pdf · doi:10.1103/physrevlett.122.074503
published in Physical Review Letters 122(7), 074503 (American Physical Society) · 5 pages, 4 figures. Supplementary Information available on request
openalex created_date 2018/10/05 · openalex publication_date 2019/02/22 · arxiv created 2019/03/09 · arxiv updated 2019/03/12 · openalex updated_date 2026/08/05
We demonstrate "bendotaxis," a novel mechanism for droplet self-transport at small scales. A combination of bending and capillarity in a thin channel causes a pressure gradient that, in turn, results in the spontaneous movement of a liquid droplet. Surprisingly, the direction of this motion is always the same, regardless of the wettability of the channel. We use a combination of experiments at a macroscopic scale and a simple mathematical model to study this motion, focusing in particular on the timescale associated with the motion. We suggest that bendotaxis may be a useful means of transporting droplets in technological applications, e.g., in developing self-cleaning surfaces, and discuss the implications of our results for such applications.