A Two Dimensional Finite Difference Model for Predicting The Temperature Profiles During Microwave Heating of Foods Having Finite Cylinder Geometry

Abstract

The development of accurate mathematical models for microwave heating of foods is necessary for the prediction of the possible hot and cold zones. A numerical model was developed to compute the temperature profiles ina finite cylinder during microwave heating, and these profiles were compared with experimental temperature profile data obtained from literature. Evaporation of moisture was not taken into account. Although the level of agreement between the experimental and predicted surface temperatures was very high absolute mean error of 3 % for potato finite cylinders, the predicted temperatures for the geometric center were significantly higher than the experimental values absolute mean error of 29.7 % . Another observation to be noted was the dependency of temperature profiles on the number of nodes used in the computations. For one data set a mesh size was chosen such that the error between the finite difference predictions and experimental data was minimized. Then the same number of nodes was used for other data sets. By this means, the absolute mean errors between experimental and numerical temperatures for 2% agar gel cylinder R = 0.035 m, H = 0.07 m were 5.5 % and 7.5 % for center and near surface temperatures, respectively

Keywords

• microwave,heating,two-dimensional model

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