Confined boiling of FC72 and FC87 on a downward facing heating copper disk

This paper presents results for FC72 and FC87 saturated and subcooled nucleate pool boiling, at atmospheric pressure, on a downward facing surface and in confined spaces between a heated copper disk (diameter 12 mm and thickness 2 mm) and an unheated surface, for distances varying between 0.2 and 13 mm. At saturated boiling and low heat flux (⩽45 kW/m2) a decrease in the distance between the plates causes an enhancement of the boiling. At subcooled boiling the results show that the heat transfer coefficient decreases with a reduction in the distance between the plates. A visualization of the subcooled boiling shows the effect of confinement and heat flux on the liquid–vapor configuration.