H123 Subcooled Boiling on the Water-Repellent Coating Surface with Spotted Patterns

Abstract

Boiling feature on a copper surface with hydrophobic coating of spotted pattern has been studied. Nucleate boiling begins at hydrophobic region at low superheating and an overshoot of superheating in boiling incipience is not observed. Heat transfer on the surface of spotted pattern is better than mirror surface. At low heat flux, generated bubble size depends on the spotted size and heat transfer is enhanced by subcooling effect. The hydrophobic coat region is effective to avoid overshoot in the low superheat region.