Experimental Investigation on Transport of Self-Propelled Leidenfrost Droplet on Herringbone and Helical Ratchet Surfaces
摘要
The Leidenfrost effect where a liquid droplet levitates and moves atop a hot solid surface due to the formation of a vapor cushion, has garnered significant attention for its potential in self-propulsion and heat transfer control. The vapor layer on which the droplet levitates significantly reduces friction and increases the droplet’s lifetime due to reduced heat transfer. Vapor flow escaping below the Leidenfrost body gets rectified by the presence of asymmetric textures so that a directional thrust drives the levitating material. The present study investigates the self-propulsion of leidenfrost droplet transport on herringbone ratchet. Experimental observations reveal the presence of the ratchet grooves provides directional guidance to the droplet, inducing controlled and rectified motion. The study explores the leidenfrost droplet transport on a herringbone ratchet by varying the orientation and distance from the center portion of the ratchet. The aspect ratio of the herringbone ratchet taken is 0.1. Through a series of carefully designed experiments, the directional stability of Leidenfrost self-propulsion of droplets on herringbone ratchet surfaces is analyzed. The herringbone-shaped ratchet propels the droplets within predetermined paths. Consequently, this enhanced directional stability study significantly contributes to the control and predictability of droplet motion.