Heat and Mass Diffusion in Porous Building Elements

Abstract

In the field of building physics, diffusion phenomena started to be extensively modeled in the 70s (because of the oil crisis) to develop building-performance-simulation programs for the adoption of rational policies of energy conservation. However, existing tools might still present inconsistent scenarios of the actual occurrences in buildings, especially in the heat and mass transfer domain. The mathematical description for predicting building hygrothermal dynamics is complex because of the nonlinearities, s three-dimensionality of transport phenomena, and interdependence of several variables. The parametric uncertainties in modeling, simulation time steps, external climate, building schedules, hygrothermal properties, ground temperature and moisture storage, and transport also contribute to the increase in this complexity.