Heating Concentrations of Microwaves in Spherical and Cylindrical Foods

A comprehensive quantification for microwave heating of dielectric spherical and cylindrical materials is presented in this paper based on extensive numerical simulations of cavity heating. The distributions of power density along the radius are studied for various foods for a radius range from 0.5 to 5.5 cm and wavelength from 1.38 to 5.4 cm. The results from numerical modeling agree with the theoretical analysis and are also verified by the thermographs and published experimental data. Moreover, both experiments and numerical predictions verify the rules that relate radii and dielectric properties to focusing, as developed in the previous paper. A heating concentration (HC) index is proposed to quantify the focusing effect of microwaves.At 2.45 GHz frequency, some foods, such aswater rich vegetables, are inherently found to be much more likely to focus energy with high HC index, while some other foods, such as salty hams, are not likely to have significant focusing at any radius.