Sustainable thin-film condensation with free surface flow through water film network

Abstract

In various energy industries, sustainable and efficient condensation is crucial for minimizing energy system size and cost. This study developed a water drainage system (i.e., a water film network), which mimicked the fast water transport through the water film on Sarracenia trichomes, for sustainably enhanced condensation even on a hydrophilic surface. The water film network absorbed and drained the surrounding microscale condensates because of the Laplace pressure difference, resulting in the continuous shedding or the thin-film condensation (< few micrometers thick). The water film network enhanced the dew harvesting efficiency by up to 577.8%, and thin-film condensation was sustained even under harsh conditions that oxidized the surface. Our findings suggest a way to sustainably enhance condensation performance without hydrophobic functionalization, and provide insights that the free surface flow through the water film channel can significantly improve the performance of thermal management systems through the minimization of the viscous pressure drop.