Pool boiling heat transfer on small heaters: effect of gravity and subcooling

Measurements of space and time resolved subcooled pool boiling of FC-72 in low, earth, and high gravity environments were made using a microscale heater array. Data from each heater in the array were synchronized with highspeed digital video. The boiling behavior was dominated by the formation of a large primary bubble on the surface which acted as a "sink" for many smaller bubbles surrounding it, Dryout of the heater occurred under the primary bubble. For a given superheat, this primary bubble was observed to increase in size with bulk fluid temperature. Boiling curves at various subcoolings and gravity levels are presented. (C) 2002 Published by Elsevier Science Ltd.