On modelling drying of porous materials: analytical solutions to coupled partial differential equations governing heat and moisture transfer

Abstract

Luikov theory of heat and mass transfer provides a framework to model drying of porous materials. The coupled partial differential equations governing the moisture and heat transfer can be solved using numerical techniques, and in this paper, we solve them analytically in a setting suitable for industrial drying situations. We discuss the nature of the solutions using the property values of pine wood. It is shown that the temperature gradients playa significant role in deciding the moisture profiles within the material when thickness is large, and the models based only on moisture potential gradients may not be sufficient to explain the drying phenomena in moist porous materials.