Manipulation of dynamic behavior of impacting droplets by surface patterns

This work explores the manipulation method for controlling the dynamic behavior of impacting droplets using surface patterns. By designing and implementing four radially patterned surfaces with strategically positioned obstacles, the study reveals the direct correlation between surface patterns and droplet behavior upon impact. The experimental results demonstrate that, the maximum stretching length of the droplet after impact is significantly inhibited due to the enhanced viscous dissipation of the droplet on these patterned surfaces. Furthermore, the formation of satellite droplets delays and the number of satellite droplets also significantly decreases. Through an analysis of energy distribution during the impact process, we concluded that the surface energy and kinetic energy of the droplets exhibit a linear growth relationship with We^0.25, whereas the dissipated energy We^0.5. As the number of obstacles increases, the viscosity dissipation of the droplet enhances during the impact, resulting in a decrease in the kinetic energy and surface energy. Consequently, the droplets become more resistant to breaking, resulting in a reduced formation of satellite droplets. Therefore, the special designed surface patterns can be expected to manipulate the stretching shape, stretching length of the droplet, and formation of satellite droplets after impacting. The findings provide valuable insights into the manipulation and control of droplet dynamics, offering potential applications in various fields such as surface engineering, anti-icing and liquid-based technologies.