EVAPORATIVE COOLING OF LIQUID-FILM THROUGH INTERFACIAL HEAT AND MASS-TRANSFER IN A VERTICAL CHANNEL .1. EXPERIMENTAL-STUDY

An experimental study is performed to study the evaporative cooling of the falling liquid film through interfacial heat and mass transfer in a vertical channel. The measured wall temperature, heat and mass transfer rates are specifically presented for the systems with water film evaporation and ethanol film evaporation over wide ranges of liquid mass flow rate, channel width and liquid inlet temperature. The results show that the influences of the evaporative latent heat transfer on the cooling of the liquid film depend largely on the inlet liquid film temperature and liquid mass rate. Effective evaporative cooling results for a higher inlet liquid film temperature and a smaller liquid mass flow rate.