3-D scanned oven geometry improves the modeling accuracy of the solid-state microwave heating process

Solid-state-based microwave ovens are promising to mitigate the non-uniformity issue for their precise controlled microwave parameters. Multiphysics modeling is a useful tool for understanding complicated microwave heating processes. However, previous models using simple or manually measured oven geometry had challenges in accurately predicting the heating patterns. This study developed a 3-D scanning approach to characterize the accurate geometric details of the cavity and incorporate it in the multiphysics modeling of solid-state microwave heating. The effect of oven geometric details on modeling accuracy was evaluated for models using the simple box, manually measured, and 3-D scanned geometries at multiple microwave frequencies and port locations. A quantitative approach was also developed to replace the previously often-used qualitative approach to compare the spatial temperature profiles between the simulation and experiments. The Multiphysics-based models using 3-D scanned geometry showed significantly or considerably smaller RMSE values (1.57 to 4.11 °C) than the models with simple box geometry (1.73 to 6.33 °C) and manually measured geometry (1.48 to 4.66 °C) at most heating scenarios. The 3-D scanned approach can accurately incorporate the irregular geometric details of the oven cavity and can improve the prediction accuracy of microwave heating models for future food products and oven development.