Bubble frequencies and departure volumes at subatmospheric pressures

Abstract Bubble frequencies and departure volumes in nucleate pool boiling have been obtained for a variety of liquids at pressures ranging from 50 to 760 mm. Hg. The bubble dynamic data conclusively show the volumetric vapor flow rate to be a strong function of the Jakob number in qualitative agreement with the heat transfer measurements of Nickelson and Preckshot. The data also indicate the volumetric vapor flow rate per cross section to be independent of the Jakob number, in agreement with existing equations.