Model development of a new single room ventilation enthalpy exchanger under wet conditions

The present paper deals with the model development of an enthalpy exchanger under wet conditions in the frame of single room ventilation. Numerous models take into account simultaneous heat and vapour transfer, but not liquid transfer. This new model takes into account condensation on stale air side, liquid transfer through porous membrane and finally water evaporation on the fresh air side. The involved phenomena depend on each other as the evaporation cools down the membrane, intensifying condensation. A coupling is then necessary, leading to spatial discretization of the exchanger and numerical considerations. An experimental set-up has been used to validate the membrane mass transfer model. The enthalpy exchanger model is then used to simulate performances under different outdoor conditions.