Pool boiling heat transfer from plain and microporous finned surfaces in saturated FC-72

The present research is an experimental study of "double enhancement" behavior in pool boiling from heater surfaces simulating microelectronic devices immersed in saturated FC-72 at atmospheric pressure. The term "double enhancement" refers to the combination of two different enhancement techniques. The present study combines a large-scale area enhancement (square pin fin array) and a small-scale surface enhancement (microporous coating). Flush-mounted, machined copper surfaces with a 1 cm x 1 cm base surface were used with fin lengths varying from 0 (flat surface) to 8 mm. Effects of this double enhancement technique on critical heat flux and nucleate boiling heat transfer in the horizontal orientation (fins are vertical) are investigated. In order to qualify the present testing techniques, a 5 cm x 5 cm flat surface was also built and tested at various inclinations and under both increasing and decreasing heat flux conditions.