Numerical Analysis of the Microwave Heating of Compacted Copper Powders in Single-Mode Cavity

Recently, microwave single-mode cavities have been used to isolate and study the effects of electric and magnetic field components on the temperature and microstructure of samples. This paper discusses the conditions affecting the heating of metal powders in this kind of experiments. In addition, it studies general trends in the interaction of microwaves with powders of different sizes and densities. As an example, it numerically analyses the microwave heating of copper powders in single-mode WR284 TE(102) cavity. The optical and thermal parameters of metal powders are estimated by means of Bruggeman's effective medium approximation combined with Mie theory. Analysis shows the strong influence of the device on the temperature of samples located in the electric field maximum. In addition, the study demonstrates the existence of standing waves inside samples. In this case, high temperature is attained easily when samples are placed in the magnetic field maximum. (C) 2011 The Japan Society of Applied Physics