Mathematical and Numerical Modeling of Drying Tunisian Loquat Slices (Eriobotrya japonica L.) Fruits

Abstract

This study aimed to examine a three-dimensional mathematical model for heat and mass transfer during hot-air convective drying of Eriobotrya japonica slices. The thermophysical, transport, and shrinkage properties of the slices were treated as variables, and an estimate of the effective moisture diffusivity (D_eff) was made, considering the Arrhenius-type relationship with temperature. Therefore, the obtained data showed that the modified Page was the best model that described the drying kinetic characteristics of Tunisian E. japonica fruits. Also, the simulated model was solved using the finite-element method, which was programmed by COMSOL Multiphysics. The selected model was validated by comparing it with experimental data, focusing on an air velocity of 1 m/s and temperatures of 50°C, 60°C, and 70°C, using the correlation coefficient (R²) and RMSE for analysis. In addition, the obtained results revealed that the moisture diffusivity (D_eff) ranged from 9.63 × 10⁻⁹ to 1.65 × 10⁻⁸ m²/s, which is dependent on the moisture ratio and dehydration temperature. The chosen model, which yielded concordance coefficients > 0.99 for the moisture ratio and temperature, accurately predicted the experimental data. The model accurately described the heat and mass transfer processes during convective hot air drying, making it suitable for food drying applications.