Coupled electromagnetic, heat and mass transport ODE model for microwave drying process

Modelling of microwave drying can not only understand the relationship between microwave and water-containing media, but also facilitate the controller design for developing production efficiency. However, there are few mathematical models, which can explicitly reveal the spatiotemporal evolution of multi-physical parameters due to the complex coupled mechanism. Motivated by this obstruction, this paper proposes an ordinary differential equation (ODE) model, which can approximately describe the dynamical characteristics on the electromagnetic propagation, heat transport and mass transport. First, the schematic illustration and assumptions are given to simplify modelling difficulties and develop computation efficiency. Then, the microwave drying model is simplified as the three submodels with the analytical expression. By applying the spatial difference method, the ODE model is proposed to approximately describe the global distribution of temperature and moisture content. Finally, the effectiveness of proposed model is demonstrated by giving a comparison simulation on microwave drying germinated brown rice.