Boiling Enhancement of Ethanol by Halloysite Nanotube coating

Abstract

Recently, the effect of wettability on boiling heat transfer has attracted a great amount of attention. Due to the difficulties in controlling the wettability of low-surface-tension fluids, there are few studies devoted to liquids other than water. In this research, effective wettability control of ethanol has been achieved by coating the copper boiling surface with a spot pattern of P(FA-C8-coDOPAm) modified halloysite nanotubes which leads to ethanol repellency. Saturated boiling on such a mixed wettability shows over 400% heat transfer enhancement over the uncoated surface. In addition, the maximum heat transfer gains have been to occur around the pitch-to-spot diameter ratio of 2.75.