Pool boiling enhancement with surface treatments

Abstract

Pool boiling heat transfer characteristics on treated surfaces were investigated experimentally. Surface treatments were performed with sandpapers, building micro structures by etching, and micro-porous coating. Copper blocks of 20 mm x 20 mm were used as test sections and PF5060 was used as a working fluid. The effect of wall superheat (0-35 K), surface orientation (0 degrees, 45 degrees, 90 degrees), and subcooling (0, 5, 10 K) on treated surfaces were also investigated. Heat transfer performance on inclined surface was better than that of horizontal surface in all test sections. Because bubble generation was suppressed by subcooling, higher wall superheat was needed to initiate boiling in all surfaces. Micro-porous coated surface showed the highest heat transfer enhancement among tested surfaces.