Droplet Dynamics on Vertical Fibers

Water scarcity is a critical challenge of our era. Nature offers us several solution paths through its diversity, whether through the elegance of a spider's thread or the interlacing scales on a lizard's back.
Inspired by these, humans developed tools such as cloud nets to tackle water scarcity on a larger scale. In this context, our research explores the dynamics of gravity-driven droplets along fiber bundles, a complex process where droplets reduce in volume and speed during descent. We used a novel method to track these changes in real time, noting a decline in droplet speed and size due to friction and capillary forces from a trailing liquid film. The use of fiber bundles, changing the substrate from smooth to grooved, increases droplet velocity but also fluid loss. This study offers valuable insights for droplet collection and instrument development, showing that altering the fiber structure can enhance cloud nets cost-effectively.