Drying of clay slabs: Experimental determination and prediction by two-dimensional diffusion models

Experiments on convective drying of clay slabs with an initial moisture content of 0.11 (dry basis, db) were performed at 50 and 90 °C. A two-dimensional numerical solution of the diffusion equation with a boundary condition of the third kind was proposed to describe the process using a constant (model 1) and variable (model 2) effective mass diffusivity value. The solution was coupled with an optimizer to determine the process parameters at each temperature using experimental datasets. The analyses of the results indicated good agreement for model 2 between each experimental dataset and the corresponding simulation.