Effect of geometrical parameters of open microchannel surfaces on pool boiling heat transfer

This study focuses on the effect of channel depth on the heat transfer coefficient during nucleate pool boiling. Experimental studies were performed for saturated deionized water, and Novec-649 as working fluids at atmospheric pressure. Copper surfaces were modified to form microchannels with different geometrical properties. The microchannels were from 0.2 mm to 0.4 mm deep, 0.3 mm wide and spaced every 0.1 mm. The experiment was conducted for increasing heat flux up to the critical heat flux point. The surface modification provided an appreciably higher heat transfer coefficient compared to the smooth surface for all boiling liquids. The maximum heat transfer coefficient obtained exceeded 60 kW/m2K.