EVAPORATION OF A HEATED FALLING LIQUID-FILM INTO A LAMINAR GAS-STREAM

Abstract

Heat and mass transfer characteristics for a falling liquid film evaporating into a gas stream were investigated. The liquid water film falls along a vertical plate subjected to a uniform heat flux. In the numerical analysis the respective governing equations for the liquid film and gas stream were solved together. An experimental system was also set up to measure the heat transfer coefficient along the wetted wall for various thermal and flow conditions. The measured data are in good agreement with the numerical predictions. It is observed that the latent heat transport connected with the vaporization of the liquid film plays an important role in the transfer processes. A correlation of the Nusselt number for heat transfer from the wetted wall to the liquid film is proposed.