Multiple droplets dynamics on cylindrical fiber

Abstract

We investigate the descent of a single droplet on a vertical fiber and its role in generating additional droplets. As the droplet slides, it deposits a non-uniform liquid film whose thickness decreases along the fiber. The thicker portion near the release point undergoes a Rayleigh-Plateau instability, leading to the formation of a new droplet. This newly formed droplet initially accelerates by accumulating fluid from the film ahead, then shifts to a decelerating phase once fluid loss at its rear dominates. Ultimately, it merges with the original droplet. This refeeding allows the droplet to travel further. Successive generations of droplets can similarly arise, governed by the evolving film thickness. We develop theoretical models that capture each phase of motion and discuss the experimental and theoretical aspects of this cascading cycle of droplet generation.