Solidification and adhesion characteristics of water droplets on smooth slippery liquid-infused surfaces

Slippery liquid-infused porous surfaces (SLIPS) demonstrate significant potential for anti‑icing applications in fields such as marine vessels, aircraft, and power transmission systems. However, the mechanisms by which the physical properties of the lubricant film influence droplet freezing remain unclear. In this study, the icing characteristics of water droplets on smooth slippery liquid‑infused surfaces (SSLIS) are investigated experimentally. The results indicate that both the thickness and viscosity of the oil film considerably affect the freezing behavior of water droplets. As the oil film thickness increases from 0 mm to 0.045 mm, the average height of frozen droplets decreases by approximately 8%, the total freezing time shortens by 20.3%, the recalescence time decreases by 35.9%, and the ice adhesion force drops by 89.8%. When the viscosity rises from 10 mPa·s to 30,000 mPa·s, the total freezing time increases by 34.5%, and the ice adhesion force grows by a factor of five. These trends are attributed to changes in the oil film viscosity and thickness, which alter the contact state of water droplets on SSLIS and lead to different nucleation temperatures on different SSLIS surfaces. Furthermore, the research has found that the surfaces of SSLIS with lower viscosity and thicker oil film have lower ice adhesion. SSLIS with higher viscosity and greater thickness demonstrate better ice removal durability. Finally, a thermodynamic theoretical model for water droplet freezing on SSLIS is established. By integrating theoretical and experimental results, a scaling relation between freezing time and freezing temperature is proposed.