Kungang Zhang, Fangjie Liu, Adam J. Williams, Xiaopeng Qu, James J. Feng & Chuan-Hua Chen
Phys. Rev. Lett. 115, 074502 (2015)
Abstract - Fiber-based coalescers are widely used to accumulate droplets from aerosols and emulsions, where the accumulated droplets are typically removed by gravity or shear. This Letter reports self-propelled removal of drops from a hydrophobic fiber, where the surface energy released upon drop coalescence overcomes the drop-fiber adhesion, producing spontaneous departure that would not occur on a flat substrate of the same contact angle. The self-removal takes place above a threshold drop-to-fiber radius ratio, and the departure speed is close to the capillary-inertial velocity at large radius ratios.