2013/07/29 by Antonin Eddi, Eddi, A., Koen G. Winkels +3
Engineering · Materials Science · #Electrohydrodynamics and Fluid Dynamics #FOS: Physical sciences #Fluid Dynamics (physics.flu-dyn) #Fluid Dynamics and Heat Transfer #Surface Modification and Superhydrophobicity
paper · pdf · doi:10.48550/arxiv.1307.7475
openalex publication_date 2013/07/29 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The coalescence of water drops on a substrate is studied experimentally. We focus on the rapid growth of the bridge connecting the two drops, which very quickly after contact ensues from a balance of surface tension and liquid inertia. For drops with contact angles below 90^∘, we find that the bridge grows with a self-similar dynamics that is characterized by a height h∼ t2/3. By contrast, the geometry of coalescence changes dramatically for contact angles at 90^∘, for which we observe h∼ t1/2, just as for freely suspended spherical drops in the inertial regime. We present a geometric model that quantitatively captures the transition from 2/3 to 1/2 exponent, and unifies the inertial coalescence of sessile drops and freely suspended drops.