EFFECTS OF THREE-DIMENSIONAL HEAT AND MOISTURE TRANSFER ON DEFORMATION AND STRESS BEHAVIORS OF MOLDED CERAMICS DURING DRYING
The objective of this study is to contribute to an optimum drying process and a precise design of mold in a ceramic production. The transient three-dimensional analysis on the viscoelastic strain-stress as well as the heat conduction and the moisture diffusion in a slab ceramics during drying by hot air were carried out simultaneously by the finit element method. The effects of drying parameters on the behaviors were discussed. The stress and the gradient of moisture content were influenced significantly by the Biot or Lewis number. When the moisture diffusion is enhanced or the drying is controlled properly so as to form a gentle gradient of moisture content in the slab, the maximum tensile stress could be reduced. The ununiform drying caused the deformation of warp and the enlargement of the maximum tensile stress.