Article

Comparison of 1D and 2D models predicting a packed bed drying

¹ Unité de Recherche Environnement, Catalyse et Analyse des Procédés URECAP, Ecole Nationale d’Ingénieurs de Gabès, Rue Omar Ibn-Elkhattab, 6029 Gabès, Tunisie
² Laboratoire d’Etudes et de Recherche sur le Matériau Bois LERMAB, Université de Lorraine-Faculté des Sciences et Technologies, Boulevard des Aiguillettes, 54506 Vandœuvre-lès-Nancy Cedex, France
³ Laboratoire d’Energétique et des Transferts Thermiques et Massiques, Faculté des Sciences de Tunis, Campus Universitaire, 2092 El Manar, Tunisie

^* Corresponding author: souad.messai@gmail.com

Received: 10 July 2013
Accepted: 13 November 2013

Abstract

A numerical study for the modelling of porous particles packed bed drying in one and two dimensions (1D and 2D) is presented in this work. This model is based on the averaging volume approach using two scale changes. Taking into account the non validity of the thermal equilibrium between the gas phase and the porous particle, a two temperatures model is then developed. The numerical resolution of macroscopic equations describing heat and mass transfer during the drying of a packed bed is carried out by the method of finite volume. Experimental data for spherical porous alumina particles reported in the literature were used for the validation of the model. A good agreement was found. The influence of particles thermophysical properties and operating variables is tested. A set of time-space evolution describes the progression of these variables with time, in the height and radius of the packed bed. The model results allow a better understanding of the heat and mass transfer mechanisms involved in a packed bed drying process.