Characterization of micro/nanoscale condensation

Dropwise condensation heat transfer has the potential for a high heat transfer coefficient, making it useful in power plants, HVAC systems, thermal management, desalination, and water harvesting. Dropwise condensation involves a repeated cycle of nucleation, growth, coalescence, and sweeping, with the initial stage of condensation occurring on a scale smaller than 1 um. To enhance the performance of heat transfer, efforts are made to accelerate the condensation cycle; however, the nucleation and growth stages are challenging to measure even with conventional microscopes. Therefore, we aim to utilize an atomic force microscope (AFM) capable of measuring at the nanoscale to observe the early stages of condensation. Specifically, we intend to measure the nucleation sites on hydrophobic coatings, the nucleation density of nanoscale droplets, and the condensation mechanism on nanostructures.