Estimation of thermo-physical properties of products with cylindrical shape during drying: The coupling between mass and heat

Abstract

This article aimed at studying drying of products with cylindrical shape, using an apparent liquid diffusion model, with coupling between mass and heat at surface of the product. Model includes variable thermo-physical properties and shrinkage. The one-dimensional diffusion equation in cylindrical coordinates, with boundary condition of the third kind (i.e., convective boundary condition), was discretized by means of the finite volume method with a fully implicit formulation. The proposed solution can be used to determine thermo-physical parameters, via optimization technique, and also to simulate water migration and heat transport. Developed software was applied to describe convective drying of whole bananas. Three experiments were carried out at average drying air temperature of 47.9, 58.6 and 66.9°C, enabling to determine the thermo-physical properties as well as to simulate the process of heat and mass transfer. The statistical indicators of the simulations made it possible to conclude that, for the three experiments, the proposed model well describes the involved processes.