Numerical analysis of evaporation from a falling film in a vertical parallel plate channel

A detailed numerical analysis is performed of evaporation from a laminar falling liquid film with a co-current laminar gas-vapour mixture flow in a vertical parallel plate channel. A finite volume method is used to obtain a fully coupled implicit solution of a complete set of parabolic two-phase two-dimensional governing equations. Comparisons with the previous numerical and experimental studies are made to demonstrate the accuracy and capability of the present numerical model. Water-air and ethanol-air mixtures are used to examine the effects of buoyancy forces on the flow and the thermal characteristics of the evaporation process. The effects on the heat and mass transfer of the system of the wall heat flux, the relative humidity, and the inlet pressure are investigated.