Controlling the residence time of a bouncing drop with asymmetric shaping

Abstract

The bouncing of a drop on non-wetted surfaces has received substantial attention because of the minimum residence time of a drop on a surface. Drop dynamics is classically limited to circular symmetry and a theoretical residence time. Thus, altering the time has been a challenging task. In this study, we investigate the bouncing dynamics of egg-shaped footprint drops to prove the concept of controlling the residence time with asymmetric shaping in an electrohydrodynamic device. The asymmetry and ellipticity of the shape provide an efficient pathway for reducing the residence time by nearly 28% below a spherical shape. The exceptional impact dynamics and the reduced contact time are characterized in terms of the geometric parameters of the shape model, which is rationalized by quantitative momentum analysis in the simulation. The distinct bounce features of the asymmetric drop can offer potential for diverse applications, such as maintaining dryness, anti-icing, and self-cleaning.