Journal of Food Engineering, Vol.116, No.1, 109-117, 2013
Coupled 3D heat and mass transfer model for numerical analysis of drying process in papaya slices
An experimental and numerical study for the drying process of a solid food, Chilean papaya slices, was carried out in a range of air temperatures from 40 to 80 degrees C. The unsteady temperature and moisture distributions results inside the sample were predicted by using an unsteady tri-dimensional coupled heat conduction and mass diffusion mathematical model. The validation procedure includes a comparison with experimental and numerical temperature and moisture content results obtained from experimental data. The samples thermophysical properties as density, specific heat, and thermal conductivity are assumed to vary non-linearly with temperature. The convective heat and mass transfer coefficients were found by the analytical model. The water effective diffusion coefficient, the drying curves and the center temperature were measured by physical experiments. It was found from the experimental results that slices of papaya present an isotropic behavior with an uncertainty between 6.0% and 9.0%. According to statistical test results (RE%), the finite volume method based calculations gave a very good fit quality. (C) 2012 Elsevier Ltd. All rights reserved.