TRANSIENT DROPLET GROWTH DURING DROPWISE CONDENSATION.

The study investigated the possibility of determining high heat-transfer rates during dropwise condensation by analyzing single condensate droplets growing on a convectively-cooled surface. A mathematical model included both the droplet and a portion of the condensing surface. Experiment utilized condensate droplets, growing on a thin copper surface, to verify the analysis. Experimental results agreed closely with predicted results--indicating high heat-transfer rates at droplet perimeters. Both experiment and analysis showed that no single vapor-to-condensing-surface temperature difference may be expected during dropwise condensation. Limitations on the calculation procedure pertaining to the region around the droplet perimeter restricted the accuracy of heat-transfer rate predictions a separate study of droplet perimeter is suggested. Author