FINITE DIFFERENCE TIME DOMAIN (FDTD) CHARACTERIZATION OF A SINGLE MODE APPLICATOR

摘要

Microwave heating plays an important role in the processing & heating of foods in the food industry and at home, but the applicator design is frequently an arduous task. The finite-difference time-domain (FDTD) method can be used to model complex geometries and guide the design of different types of applicators. In the reported research, the FDTD approach has been employed to characterize the electric field distribution of a rectangular waveguide applicator, carrying TE_(10)-mode aperture field distribution, terminated in an oversize rectangular waveguide/ cavity and operating at 915 MHz. A comprehensive study was carried out to evaluate the mode/field distribution in the empty cavity box as a function of its geometrical dimensions. Power deposition profile throughout the volume of a packaged food, and scattering parameters as a function of food properties and surrounding environment were computed, by using a realistic food-engineering model. Good agreements between modeling and experimental results were obtained. The results demonstrated the usefulness of numerical simulation in predicting and characterizing the electromagnetic (EM) field distributions in microwave applicators used in food processing.