Heater size and gravity effects on pool boiling heat transfer

Pool boiling heat transfer measurements from heaters of various sizes were obtained in low gravity aboard the KC-135. Visual observations indicate boiling in earth and high gravity can be dominated by surface tension effects exhibiting behavior similar to microgravity boiling. Surface tension dominated boiling occurred in earth and high gravity when the bubble departure diameter was greater than the heater length. The Bond number at bubble departure was not constant across gravity levels and heater length scales, and was found to depend additionally on the wall superheat and the bulk fluid subcooling.