72th Annual Meeting of the APS Division of Fluid Dynamics (November 23, 2019 — November 26, 2019)

V0024: Superwalking droplets

Authors

• Rahil Valani, School of Physics and Astronomy, Monash University, Victoria 3800, Australia
• Anja Slim, School of Mathematics and the School of Earth, Atmosphere and Environment , Monash University, Victoria 3800, Australia
• Tapio Simula, Centre for Quantum and Optical Science, Swinburne University of Technology, Melbourne

DOI: https://doi.org/10.1103/APS.DFD.2019.GFM.V0024

On vertically vibrating a bath of silicone oil, droplets of the same oil can be made to walk on the liquid surface. This walking droplet, also called a walker, creates a local wave each time it bounces on the fluid trampoline. The waves in turn push around the walker, giving rise to a moving wave-particle entity. By vibrating the bath at two driving frequencies, f and f/2, we have observed a new class of walking droplets which we coin superwalkers. Superwalkers may be more than double the size of the largest walkers and may travel at more than triple the speed of the fastest ones. Being bigger and faster, enable these superwalkers to overcome their wave barriers and get very close to other superwalkers, resulting in a new kind of interaction. This interaction gives rise to plethora of novel multidroplet behaviors.