Numerical modeling and simulation of microwave heating process

Abstract

The use of induction heating and RF drying in the processing and curing of materials has been in commercial use for over 20 years. New high-conductivity ceramics are being developed which require delicate drying and sintering processes. The authors use the finite-difference time-domain method (FDTD) to examine the feasibility of using induction heating in same delicate high-conductivity ceramic drying processes in which uniformity of the electromagnetic power deposition pattern in the sample is critical. Furthermore, FDTD was used to simulate the RF drying process in which a ceramic ware is placed on a conveyor belt moving between two capacitor electrodes. The finite-difference time-domain method, using the Yee cell, provides an effective way to analyze the effects of material properties, ware shape and dimensions, and the frequency of operation on the microwave drying processes. The FDTD method displays both the dynamic behavior and the steady-state behavior of the microwave heating process. FDTD results of the induction and RF drying processes are shown and guidelines to help optimize the performance of both drying processes are presented. Specifically, coil pitch, coil diameter, and frequency of operation are investigated, while for the RF drying process, the electrode spacing and sample shape, dimensions, and orientation are evaluated. >