Experimental and numerical study of microwave drying in unsaturated porousmaterial

The drying of unsaturated porous material due to microwave drying (2.45GHz) has been investigated numerically and experimentally. Most importantly, th is work focuses on the influence of moisture content on each mechanism (vap or diffusion and capillary flow) during microwave drying process. Based on a model combining the electric field and heat-mass transport equations show that the variation of initial moisture content and particle size changes t he degree of penetration and rate of absorbed energy within the material. T he small bead size leads to much higher capillary forces resulting in a fas ter drying time. (C) 2001 Elsevier Science Ltd.