Droplet splashing dynamics on cryogenic surfaces

The droplet splashing is a prevalent phenomenon observed in various contexts, ranging from natural rainfall to industrial processes, such as inkjet printing and spray cooling. Although extensively studied at ambient temperatures and moderately low temperatures, its behavior under extreme supercooling—specifically cryogenic conditions below −150 °C—remains largely unexplored, despite its importance for cryogenic fluid management, low-temperature manufacturing, and space exploration. Here, we investigate the splashing behavior of multiple liquid droplets interacting with smooth cryogenic solid surfaces using a cryogenic experimental platform. Our results reveal that splashing is not significantly suppressed by freezing even under deep supercooling, as solidification occurs over timescales orders of magnitude longer than those of splashing initiation. However, splashing is progressively inhibited with reduced droplet size and is further modulated by liquid properties, including viscosity, surface tension, and density. By integrating a wavelength model with a lift force model, we establish a predictive theoretical framework that quantitatively correlates the splashing threshold with droplet characteristics and ambient gas properties. These findings advance the understanding of interfacial fluid dynamics in cryogenic environments and offer practical insights for the development of cryogenic technologies.