Visualization Study of Droplet Impact Phenomena on Micro-, Micro/Nano-Textured Surfaces and Lubricant Infused Surfaces
In this study, visualization of droplet impact on hydrophobic micro-, micro/nano-textured surfaces and lubricant infused surfaces was performed. Experimental specimens were fabricated using MEMS (micro- electromechanical systems) techniques and droplet impact with pure water was visualized at various Weber number range (2 < We < 200) using a high speed camera at 8000 frames per second. Through this study it was confirmed that, various droplet impact behaviors were appeared as the Weber number was increased and the Weber number at which droplet impact behavior changes was affected by surface characteristics. Particularly, on the lubricant infused surface (LIS) after droplet impact retraction velocity is reduced by the lubricant viscosity effect during contraction process of droplet to improve the droplet deposition behavior on the surface. It was confirmed that droplet break up phenomena caused interfacial instability was slightly delayed on LIS due to the viscous dissipation effect during droplet impact process.