INTENSIFICATION OF HEAT TRANSFER IN A DOWNWARD LIQUID-FILM FLOW

摘要

Heat transfer in a film flow of the FC-72 dielectric liquid down a vertical surface with an embedded 150 x 150 mm heater is experimentally examined in the range of Reynolds numbers Re = 5-375. A chart of liquid-film flow modes is constructed, and characteristic heat-transfer regions are identified. Data on the dependence of heater-wall temperature and local heat flux at the axis of symmetry of the heater on the longitudinal coordinate are obtained. Local and mean heat-transfer coefficients are calculated. It is shown that enhanced heat transfer is observed in the region where rivulets starts forming in the low-Reynolds-number liquid-film flow.