Heat and moisture transport in porous materials involving cyclic wetting and drying

Abstract

Computational modeling of coupled heat and moisture transport in porous building materials with hysteretic moisture transport and storage parameters in the conditions of difference climate is presented in the paper.A diffusion-type model is used for the description of coupled heat and moisture transport.An empirical procedure is chosen to describe the path between the transport and storage parameters corresponding to wetting and drying.In a practical example of computer simulation, a concrete wall provided with exterior thermal insulation is analyzed.Computational results reveal very significant differences in moisture and relative humidity profiles calculated using the model with hysteretic parameters and without hysteresis.As the differences are on dangerous side from the hygrothermal point of view, the application of hysteretic moisture transport and storage parameters in computational models can be considered as quite important for service life analyses of multi-layered systems of building materials.