The heating of multi-layered materials by microwave heating with rectangular wave guide has been investigated numerically and experimentally. The multi-layered materials, which consist of the layer of higher dielectric material (antireflection layer) and lower dielectric material (sample), have the convergent effect of the incident microwave in sample, and it can change the heating pattern in the sample with ease. In this study, the effect of an antireflection layer thickness on the heating process is clarified in detail, considering the interference between incidents and reflected waves in the dielectric materials. Based on a model combining the Maxwell and heat transport equations, the results showed that when a layer of lower dielectric material is attached in front of sample, the microwave energy absorbed and distribution of temperature within the sample are enhanced. The predicted results are in agreement with experimental results for microwave heating of multi-layered materials using a rectangular wave guide.

Issue Section:
Technical Notes
Keywords:
microwave heating, heat transfer, multilayers, rectangular waveguides, antireflection coatings, Maxwell equations, Heat Transfer, Materials, Microwave, Modeling, Numerical Methods, Thermal
Topics:
Microwave heating, Microwaves, Temperature, Waveguides, Electric fields, Heating, Heat, Waves, Heat transfer, Dielectric materials
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