Paper presented to the 10th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Florida, 14-16 July 2014.
Bubbles condensing in subcooled water were
experimentally studied in the aim of characterizing the
nucleation behavior dependence on the water pool subcooled
temperature. A single artificial cavity was created on a brass
plate and heated by a laser beam in a water pool and high speed
camera was used to capture bubble growth dynamics. Postprocessing
allows the measurement of important parameters
such as bubble volume, rising velocity, departure diameter,
detachment frequency, volume variation versus time and
temperature and dry spot diameter. Three growth regimes were
identified according to the bulk temperature and the heat flux
supplied: an equilibrium regime, a standard nucleate boiling
regime and a boiling crisis regime in which we observed the
formation of a large dry spot on the solid surface. The absence
of rewetting of the cavity is a key feature of this regime. The
obtained results are compared with the few experimental
correlations available in the literature.
