A Theoretical Model for Unsteady Coupled Heat and Mass Transfer Phenomena in Industrial Dryers

An analytical method is proposed to investigate the combined heat and mass transfer phenomena taking place in industrial dryers. The unsteady heat and mass transfer equations are solved analytically to obtain the distributions of the fluid and solid temperatures and the solid humidity. At the fluid and solid interface, due to the temperature and concentration gradients in the fluid and in the solid, the governing equations are coupled. One of the principal aims of the current research is to propose an analytical method for estimation of the required time for drying of a solid material. For the case of e = 0.03 and delta = 0.09, the results show that the solid is dried in approximately 25 min while for the case of e = 0.5 and delta = 1.5, the required time of drying is almost 600 min.