Abstract
An ammonia/water mixture can be used as an efficient working fluid in several industrial applications such as in heat pumps, heat transformers and separation processes. This paper presents a numerical analysis of coupled heat and mass transfer by mixed convection during water/ammonia binary liquid film evaporation inside vertical channels. The two channel walls are isothermal, but maintained at different temperatures. One wall maintained at (T-w) is covered with an extremely thin liquid film, while the other wall which is maintained at (T-p) is dry. The conducted simulations enable the analysis and the description of the evaporation process and the heat and mass transfers for a wide range of parameters including the inlet variables of each liquid and the inlet properties of the gas. The results focused on the effect of the inlet amount of water vapour and that of ammonia vapour on the evaporating rates of these two components as well as on the distribution of the concentration profiles.