Thresholds in Breaking Capillary Bridges

Fluid droplets can be driven by the geometry of the underlying solid substrate. The modulation of liquid bridges impacts processes such as wet adhesion in insects and feeding mechanisms in shorebirds. Investigating the geometric parameters involved in the breakup of capillary bridges, we observe the existence of thresholds across which drastic changes in behavior occur. Notably, in the case of liquid bridges between angled supports, a critical angle emerges, resulting in a significant transition in post-breakup volumes. To understand this complex hydrodynamic process, we build simple theoretical models and find that the seeds of the critical phenomena exist in the static liquid bridges. This understanding could provide fine-tuned fluid control and the potential for employing metamaterials in droplet manipulation.