Sensitivity analysis of intermittent microwave convective drying based on multiphase porous media models

摘要

In this study fundamental models were used by considering heat and mass multiphase transport in a porous medium which was coupled with the intermittent microwave convective combination drying process. The models were validated by experimental data sourced from references, and independent analysis was conducted to select a suitable mesh and time step. Sensitivity analysis was performed using different empirical formula-type input parameters. The water activity and the thermal conductivity mainly influenced on the temperature of the sample, and had no effect on the simulation outputs of moisture content; relative permeability of gas and the capillary diffusivity mainly had an impact on the moisture content of the sample; the specific heat, the binary diffusion coefficient and the dielectric loss factor affected both temperature and moisture content at the same time; the relative permeability of water and the dielectric constant both had no effect on the simulation results. In addition, a sample with a lower thermal conductivity, a higher capillary diffusivity or a higher binary diffusion coefficient tended to form a drier interior as well as a moister surface; a sample with a higher thermal conductivity or a higher specific heat tended to form a more uniform temperature; a sample with a higher capillary diffusivity tended to form a more uniform moisture content.