Influence of coalescence-induced droplet jumping by W-shaped groove structures on superhydrophobic surfaces

The coalescence-induced droplet jumping phenomenon on superhydrophobic surfaces has been demonstrated to have significant potential in chip-related applications, including efficient heat dissipation, enhanced corrosion resistance, and effective anti-icing performance. The current research landscape on superhydrophobic surfaces predominantly focuses on single-groove or convex configurations for droplet jumping behavior, which exhibit limited efficacy in enhancing energy conversion efficiency. In this study, a W-shaped groove structure comprising dual V-grooves was designed on superhydrophobic surfaces, with optimal parameters determined through experimental optimization. This configuration achieved a maximum droplet jumping velocity of V* j = 0.65 and an energy conversion efficiency of η = 35.04%, representing an 8.76-fold improvement over conventional flat superhydrophobic surfaces. Numerical simulations revealed that the dual-groove geometry and central convexity of the W-shaped structure reduced droplet coalescence time and amplified energy conversion efficiency. Additionally, the influence of W-shaped grooves on asymmetric droplet coalescence-induced jumping was systematically investigated. These results provide a theoretical framework for advancing surface engineering in condensation heat transfer, defrosting, and corrosion prevention applications.