System Dynamics of the Water Droplet Impacting Flexible Cantilever Beams

In this work, a water droplet impacting superhydrophobic flexible cantilever beams is systematically studied via experimental methods, aimed at recognizing the significance of the system dynamics that arises from the interplay between substrate oscillation and droplet impact. Influences of the substrate stiffness and the impact Weber number on the substrate oscillation and droplet impact dynamic are the focus particularly. For substrate oscillations, the beam deflection increases with the Weber number but decreases with the beam stiffness, while the oscillation period of the beam is not affected by the impact dynamic. For the droplet impact dynamic, the spreading dynamic is independent of beam oscillation, while the retraction dynamic is closely related to the surface elasticity. The effect of the cantilever beams on the droplet (i.e., promoting or inhibiting the rebound behavior) is dependent on the coupling movement of the water drop and the cantilever beam, which is varied by changing the stiffness of the cantilever beam. The findings of this work will provide a theoretical reference for the application of flexible substrates in the fields of anti-icing and self-cleaning.