Moisture migration and condensation within porous material

Abstract This paper is concerned with the analytical study of moisture diffusion, convection and condensation within porous material. Applying the concentration and energy balance principles, we describe the one‐dimensional steady‐state moisture migration through the porous material from one side exposed to a humid environment, and film condensation on the other side of the cold plate. The temperature at the condensation interface is calculated iteratively to yield the concentration and temperature profiles in the moist‐air region, and the film thickness and condensation rate in the condensate zone. Results are examined and discussed for typical porous insulation material and indoor conditions. Dependency on the critical relative humidity, above which condensation outside the liquid film region will occur, on the ambient temperature is presented in a psychrometric chart.