An improved model for the drying of porous solids with abruptly changing permeability

Abstract

We present the simulation of the drying of porous solids with abruptly changing permeability using the Darcy-Forchheimer equations. This model arises in fluid mechanics through porous media when the flow exhibits moderate to high velocities and can be useful to predict the drying rate of the first drying period, which is usually constant. The presence of abrupt changes in permeability creates strong singularities and makes it difficult to obtain accurate predictions of the fluid flow, velocity, and pressure drop. In order to overcome these difficulties, we apply an adaptive finite element method based on a simple a posteriori error indicator, reliable and locally efficient, that allows us to refine the mesh over the singularities. We also present a semi-analytical method to obtain an accurate measurement of the apparent permeability of a porous medium. Finally, we provide some numerical experiments that illustrate the performance of the method.