2018/01/04 by Kartik Regulagadda, Regulagadda, Kartik, Shamit Bakshi +4
Engineering · Materials Science · Physics and Astronomy · #FOS: Physical sciences #Fluid Dynamics (physics.flu-dyn) #Fluid Dynamics Simulations and Interactions #Fluid Dynamics and Heat Transfer #Soft Condensed Matter (cond-mat.soft) #Surface Modification and Superhydrophobicity #cond-mat.soft #physics.flu-dyn
paper · pdf · doi:10.48550/arxiv.1801.01247
8 pages, 4 figures
arxiv created 2018/01/04 · openalex publication_date 2018/01/04 · arxiv updated 2018/01/08 · openalex created_date 2018/01/12 · openalex updated_date 2026/07/28
Water drop impacting a superhydrophobic surface (SHS) rebounds completely with remarkable elasticity. For such an impact, the balance between the inertial and capillary forces ascertain the contact time. This is found to be fairly constant for any macroscopically flat SHS and for a given drop volume. Recently, various studies have shown that breaking the radial symmetry during the drop impact can significantly reduce the contact time below that of a flat SHS. One such study has been performed on a cylindrical SHS with a curvature comparable to the drop. The reduction in contact time has been attributed to the radially anisotropic flow imparted by the tangential component of momentum and the elliptical footprint of the drop during the crash. Here, we perform drop impact experiments on bathtub-like SHS and show that the radial anisotropy can be triggered even in the absence of both the criteria mentioned above. This is shown to be a consequence of the lamella deflection during the spreading of the drop. The reduction in contact time is quite clearly evident in this experimental regime.