3D Multiphysics simulation of microwave heating of bulk metals with parametric variations

Microwave processing of metal base material is a novel and energy-efficient technique. Microwave heating of bulk metal is an emerging method with cost, time, and energy savings over conventional heating methods. This numerical study uses the finite element method-based COMSOL Multiphysics tool to analyse the microwave heating properties of a bulk metal sample. Further in this study, the effects of tooling design assembly and microwave power parameters have been analysed for temperature profile and electric field distribution. The outcome of parametric variations has been analysed in terms of electric field distribution, heating uniformity, temperature gradient, and energy requirement. Experimental results coincided with simulated results in terms of time-temperature characteristics within ±5% error. The heating uniformity of bulk metal can be achieved at low power with small-size component whereas high power creates thermal heterogeneity with high energy consumption. The cylindrical casket geometry shows uniform field distribution with rapid heating of the specimen compared to prismatic geometry. Susceptor's dielectric properties have a significant effect on the homogeneity of the process, and the heating efficiency of the irradiated specimen. The present simulation model can be used to control the heating rate of bulk metal considering various dynamic parametric properties for a complex microwave hybrid heating process.