Apple Convective Drying - Part I: Finite Elements Parametric Study for Appraising the Operating Conditions Effects

Abstract

Drying of biomaterials such as agro-food products includes mass, momentum and energy transport coupled with shrinkage of the porous material which have important impacts on the final quality and energy consumption. These materials present non-linearity when going through deformations that affect the transport process in critical way. Therefore, it's important to realize a finite element modeling and simulation of this phenomenon. In this paper apple convective drying process is investigated. The hydro-thermo-viscoelastic behavior of this phenomenon is modeled and simulated using COMSOL Multiphysics. The grid independency test is checked and the validation of the model is performed by comparing the present results with former predictions and measurements for temperature and water content time evolution under conditions: T = 50-70 °C, V = 1.5 m/s and HR = 20%. The present results show good agreement with reference predictions and measurements. The aim of the study is to analyze the influence of some of the most important operating factors, namely humidity, temperature and velocity of the drying air on the performance of drying process of an apple slice.