EFFECTIVENESS OF COMPOSITE COPPER GRAPHITE FLUORIDE PLATINGS FOR PROMOTING DROPWISE CONDENSATION OF STEAM - A PRELIMINARY-STUDY

Composite platings of copper and graphite fluoride codeposited on soli d copper substrates were tested as potential promoters of dropwise con densation of steam. It was confirmed that steam condenses dropwise on the platings. Despite their exceptionally strong ''water repellency'' in an ordinary sense, however, we found no reduction, using the compos ite platings in place of conventional promoters, in the critical depar ture size of condensate drops, which disappointed us in the idea of us ing such platings to produce a more enhanced condensation heat transfe r. A hypothetical explanation is made on the apparent inconsistency be tween the manner of water-to-plating contact in the air and that in a condensing steam.