Re-spreading behavior of droplet impact on superhydrophobic surfaces at low Weber numbers

Despite extensive research on droplet impact behavior superhydrophobic surfaces at high Weber numbers, there remains limited understanding of their dynamics low particularly during the retraction stage. In this study, we investigate dynamic characteristics and reveal a unique re-spreading stage smaller numbers. A critical number to trigger is identified as 4.9. dimensionless analysis force, characterized by pressure, shows that phenomenon result competition between inward motion driven inertial effect outward expansion caused capillary oscillations contact line, which occurs only Such study offers insights into numbers implications for related applications, such trickle bed reactors defrosting/deicing.