Nucleate pool boiling in microgravity environment

An experimental investigation of sub-cooled nucleate pool boiling with R113 in microgravity is reported. A ballistic trajectory during a rocket flight is used to achieve a microgravity level of a/g = 0.0001 for 350 sec. Within this test time, three heat flux levels were used. A platinum wire was employed as the heating surface and, by means of resistance measurements, its mean temperature is measured simultaneously. In the region of pure heat conduction, comparison is made to a numerical solution. Results of heat flux versus Delta T under normal and microgravity are presented. It is demonstrated that a simple evaporation/condensation model for the heat transport mechanism produces agreement with the measurements.