Simulation of three-dimensional heat and mass transfer phenomena during convectional drying of carrot

The aim of this study was a three-dimensional simulation of the heat and moisture transfer process in food drying operations. A three-dimensional geometric model of carrot slices was used for simulation. The domain was discretized into 1017 tetrahedral elements, with a freedom degree of 30550. Governing differential equations of heat transfer and moisture transfer during the carrot drying process were solved under different drying air temperatures based on the finite element method using the Comsol Multiphysics 3.5 software. The equation was solved by considering the variable engineering properties of carrots. The temperature and moisture profiles were predicted at different drying conditions. In addition, some experiments were performed to obtain the engineering properties of carrot slices, such as bulk and true density and the effective moisture diffusion coefficient during hot air drying at different thicknesses of slices and air temperatures. The predicted data were compared with the experimental data. Results showed that the model can accurately predict the moisture and temperature variation of the sample during the drying process. Prediction accuracy was 99.87 to 99.98 %, and the error was 3.5 to 19 %. Therefore, the developed simulator can be highly accurate for other agricultural products with similar engineering properties