Transfer function model and frequency domain validation of moisture sorption in air-conditioned buildings

Moisture transfer in building components and furnishings has significant effect on indoor air humidity and latent cooling load. Many mathematical models and calculation methods have been proposed to evaluate this effect. Simple but accurate models are what the users expect. Investigation shows that the one-dimensional linear moisture transfer model, which uses the vapor pressure as the unique driving potential, is both very simple and well match the real moisture transfer characteristics of most air-conditioned buildings. Frequency analysis shows completely consistent characteristics between the transfer function model of moisture sorption by interior surface materials and the one-dimensional linear moisture transfer model through the entire wall within the frequency range that should be concerned. It also shows that the moisture penetration across the wall is neglectable. The transfer function model of moisture sorption by interior surface materials is not only very simple but also has satisfactory accuracy to evaluate the moisture transfer effect of buildings on indoor air humidity and latent cooling load.