2013 Volume 19 Issue 5 Pages 765-771
This research was conducted to study heat transfer in Japanese pears based on their exact geometry as measured by a 3D laser scanner. Some of the thermal properties of three cultivars of Japanese pear (Pyrus pyrifolia) were measured, boundary conditions were defined and heat transfer modeling was conducted using COMSOL Multiphysics 4.2a software based on the finite element method. The thermal conductivity of each examined cultivar was estimated from the model and found to be 0.66 ± 0.01, 0.56 ± 0.09 and 0.58 ± 0.06 W/m·K for Kosui, Niitaka and Oushu, respectively, which are acceptable comparing to other fruits. The thermal diffusivity of the cultivars was also calculated and was in the range of 1.37 × 10−7 to 1.76 × 10−7 m2/s. Low RMSE values of the model results compared to experimental data were observed. The model was validated with data obtained from a thermal camera and the results showed that the model is successful in predicting the temperature profile inside the fruit at any time.