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 degrees C) than the models with simple box geometry (1.73 to 6.33 degrees C) and manually measured geometry (1.48 to 4.66 degrees 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.