Abstract
The numerical study of coupled heat and mass transfer during the evaporation of flowing liquid film has been analysed. The film falls down on one plate of a vertical channel under free convection. The wetted plate is covered with a thin porous layer and externally subjected to a uniform heated flux while the second one is dry and isothermal. The liquid consists of pure water film while the gas mixture has two components: dry air and water vapour. The results concern the influence of porosity and porous layer thickness of the porous media on the coupled heat and mass transfer performance and on the film evaporation. The results show that, in the free convection, the presence of the porous layer enhances the heat and mass transfer performance at the liquid-gas interface during the liquid film evaporation.