Effect of Steam Flow Rate and Storage Period of Superhydrophobic-Coated Surfaces on Condensation Heat Flux and Wettability

The jumping-droplet phenomenon occurring on superhydrophobic (SHPhob) surfaces under special conditions may be beneficial for numerous systems using condensation, due to the reported increased heat transfer coefficients. One technique create a SHPhob surface is coating, which can applied larger areas of existing elements. However, challenges are associated with coating stability and realization continuous dropwise condensation. This research examined condensation steam at different flow rates (2, 4 6 g/min) its influence flux water contact angles spray-coated aluminum samples. Special emphasis impact time was addressed through series one five-hour experiments samples storage periods (coated either year ago or shortly before testing). Over experimental higher rate (6 g/min), decreased by 20% old-coated transferred from (147°) hydrophobic (125°) region. attributed joint effects partial washout adsorption condensed within porous structures during new-coated could sustain more than fifty hours keeping same fluxes characteristics.