Abstract
A mathematical model was developed to simulate in 2D the spatio-temporal evolution of the moisture content, the temperature and the mechanical stress within a deformable and saturated product during convective drying. A comprehensive hydro-thermal model had been merged with a Maxwell model with two branches, assuming a viscoelastic material, a plane deformation and an isotropic hydric-shrinkage of the sample. A long sample of clay mixture with a square section was chosen as an application case. The transport and equilibrium properties of the product required for the modeling were determined from previous experiments which were independent of the drying trials. In order to validate the hydro-thermal part of the model, several drying tests were carried out for different values of temperature, relative humidity and air velocity in a vertical drying tunnel (designed and constructed in the LETTM laboratory). The theoretical and experimental results appeared in good agreement. The simulations of the spatio-temporal distribution of mechanical stress were performed and interpreted in terms of product potential damage. The sample shape was also predicted all aver the drying process with reasonable accuracy.