Rebound dynamics of multiple droplets symmetrically/asymmetrically impacting macrotextured superhydrophobic surfaces

The rebound dynamics of multiple impinging droplets is investigated and compared under the symmetrical and asymmetrical impact conditions. The result shows that at various relative velocities, when multiple droplets symmetrically impinge macrotextured superhydrophobic surfaces, the rebound modes consist of the left–right non-simultaneous rebound (LRNSR), the coalescence-split simultaneous rebound (CSSR) and the right-left non-simultaneous rebound (RLNSR). With the transition of rebound modes, the contact time is first reduced under the LRNSR mode and then constant under the CSSR and RLNSR modes as the relative velocity is increased. Whereas when multiple droplets asymmetrically impinge macrotextured superhydrophobic surfaces, the rebound modes consist of the left-ridge-right rebound (LRIRR), the left–right-ridge rebound (LRRIR) and LRNSR. When the relative velocity is increased, the contact time is first reduced under the LRIRR mode and then constant under the LRRIR mode. But under the LRNSR mode, the first reduced and then constant contact time appears with increased relative-velocities. © 2024 Elsevier Ltd.