Main content area

Development and experimental validation of a multiphysics model for 915 MHz microwave tempering of frozen food rotating on a turntable

Miran, Welat, Palazoğlu, T. Koray
Biosystems engineering 2019
cameras, dielectric properties, frozen foods, mathematical models, surface temperature, systems engineering, temperature profiles, tempering
The objective of this study was to develop and experimentally validate a numerical model for microwave tempering of frozen food rotating on a turntable. Tempering in the cylindrical cavity of a 915 MHz microwave system (maximum power 5 kW) was modelled using COMSOL Multiphysics and the RF module. Shrimp was used as the model food since its dielectric properties at 915 MHz and thermophysical properties within the temperature range studied were available in the literature. Microwave tempering was simulated at two different power levels (500 W and 1 kW). Rotational movement was incorporated into the model by rotating the microwave system around the stationary food instead of rotating the food. Experimental validation was carried out by comparing the simulated temperature profiles to experimental ones at four different internal locations (centre, midway to the edge, edge, and corner). Root mean square error (RMSE) values were calculated for comparison. Surface temperature distributions predicted by the model and measured by a thermal camera were also compared. Acceptable agreement was found between the model and the experimental results. The developed model proved to be useful in optimising system design and processing conditions.