Investigation of Evaporation of Droplet on Patterned Substrate

Using drop shape analysis, evaporation of water droplet on patterned substrate were investigated. The results show that evolutions of contact angle and contact diameter depend crucially on the solid fraction in contact with the liquid. With decreasing this fraction, static contact angle of this system increased linearly while a jump in the contact diameter, which was caused by the transition from Cassie state to Wenzel state, appeared and became more and more remarkably. The results will not only help to understand the basic physical mechanism of evaporation, but also serve as important starting point of considering Cassie, Wenzel state and transition between them.