Droplet impact on a rapidly spinning superhydrophobic surface: Shortened contact time and reduced collision force

Abstract

Despite extensive research on the impact of motionless superhydrophobic surfaces, the understanding of droplet impact behavior on spinning superhydrophobic surfaces had been limited and not adequately explored. Here, we used the template method to create a low-cost, low-adhesion, and highly water-repellent layered superhydrophobic surface. By employing a combination of experimental observations and simulation techniques, we successfully determined the contact time and collision force. Building upon these findings, our study further delved into the dynamics of droplet impact on both the center and eccentric of a spinning superhydrophobic surface. In the case where the droplet impacted at a distance of 5 mm from the center of rotation, we observed a significant reduction in contact time by 36.4 % and a decrease in the maximum collision force by 22.5 %. This could be attributed to the spinning motion of the superhydrophobic surface, which exerted frictional force on the droplet. Our findings provided a strong theoretical foundation for achieving better water repellency by combining spinning solids with superhydrophobic surfaces.