The increased heat transfer achieved through dropwise condensation, as compared to filmwise condensation, has the potential to substantially impact a variety of applications including high-heat flux thermal management systems, integrated electronics cooling, and various industrial and chemical processes. Here, we report stable dropwise condensation onto biotemplated nanostructured super-hydrophobic surfaces. We have demonstrated continuous droplet coalescence and ejection at diameters of less than 20 μm and compared directly with flat hydrophobic surfaces. The self-ejection mechanism characteristic of dropwise condensation has been shown using a simple bio-nano-fabrication technique based on the self-assembly and mineralization of the Tobacco mosaic virus (TMV). This process is extendable to commercially relevant nanomanufacturing of both microscale electronics devices as well as large-scale large-area industrial equipment. This manufacturing flexibility is unique as compared to many other micro/nano-structured surfaces fabricated to demonstrate similar increases in condensation heat transfer.
Numerical simulation of dropwise condensation over hydrophobic surfaces using vapor-diffusion model