A drying model for three-dimensional shrinking bodies

摘要

A mathematical model to predict the drying kinetics of shrinking bodies was proposed, assuming unidirectional drying and three- dimensional shrinkage. The differential equation for mass transfer in a finite slab was solved, using boundary conditions of the first kind. The model was numerically solved by finite differences, taking into account a convective term in the mass balance equation, which appears as a consequence of non-unidirectional shrinkage. This additional term significantly changed the value of the pre- dicted diffusion coefficient. Differences when compared with previous solutions are significant for drying of solids with high initial moisture content.