Drying-Induced Stresses during Convective and Combined Microwave and Convective Drying of Saturated Porous Media

The formation of drying-induced stresses as well as the drying characteristics are analyzed in the cases of convective and combined convective-microwave drying of a clay sample. A mathematical model describing simultaneous heat and mass transfer coupled to mechanical equilibrium equation was developed. The numerical solutions obtained for both configurations (convective, convective-microwave) show different distributions of temperature, moisture content, and drying-induced stresses within the clay sample. It is shown that microwave internal heating generates lower internal stresses than continuous convective drying.