Abstract:Established simulation model of membrane humidification to research humidifier characteristics in the process of heat and mass transfer. And an analysis was made of the effect of structural parameter and gas parameter in this process. The main conclusions are as follows: Increased pressure in wetside will lead an increase of water vapor molecules osmotic amount. The dryside pressure increases, while the amount of water molecule penetration would reduce. And in another aspects, effects of gas humidity on water vapor molecules osmotic amount is similar to that of pressure. The heat and mass transfer performance of counter flow layout is better than that of downstream layout, so which the former is preferred on flow channel layout choice.