Moisture-related damage is an important issue when looking at the performance of building envelopes.In order to accurately predict the moisture behaviour of building components, building designers canresort to Heat, Air and Moisture (HAM) models. In this paper a newly developed heat and mass transfermodel that is implemented in a 3D finite volume solver, Fluent®, is presented. This allows a simultaneousmodelling approach of both the convective conditions surrounding a porous material and the heat andmoisture transport in the porous material governed by diffusion. Unlike most HAM models that oftenconfine to constant convective transport coefficients it is now possible to better predict these convectiveboundary conditions. An important application of the model is the convective drying of porous buildingmaterials. Especially during the first drying stage, the drying rate is determined by the convectiveboundary conditions. The model was validated against a convective drying experiment from literature, inwhich a saturated ceramic brick sample is dried by flowing dry air over one side of the sample surface.Temperature and relative humidity measurements at different depths in the sample, moisture distributionprofiles and mass loss measurements were compared with simulation results. An overall goodagreement between the coupled model and the experiments was found, however, the model predictedthe constant drying rate period better than the falling rate period. This was improved by adjusting thematerial properties. The adjustment of the material properties was supported by neutron radiographymeasurements.
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