Microtube Surfaces for the Simultaneous Enhancement of Efficiency and Critical Heat Flux during Pool Boiling

Boiling is an essential process in numerous applications including power plants, thermal management, water purification, and steam generation. Previous studies have shown that surfaces with microcavities or biphilic wettability can enhance the efficiency of boiling heat transfer, is, transfer coefficient (HTC). Surfaces permeable structures such as micropillar arrays, contrast, significant enhancement critical flux (CHF). In this work, we investigated microtube structures, where a cavity defined at center pillar, structural building blocks to HTC CHF simultaneously controllable manner. We demonstrated simultaneous enhancements up 62 244%, respectively, compared those smooth surface. The experimental data along high-speed images elucidate mechanism for bubble nucleation occurs cavities increased microlayer evaporation around sidewalls CHF. Furthermore, combined micropillars microtubes create further by achieving path separate nucleating bubbles rewetting liquids. This work provides guidelines systematic surface design has important implications understanding mechanisms.