Freeze-drying modeling via multi-phase porous media transport model

A multi-phase porous media transport model is built using distributed sublimation front approach and fixed grid meshing in order to simulate the freeze drying process. The model is tested numerically in multi-dimensions using 1D, 2D and 3D models. Models are solved for different aspect ratios with different heating methods like surface radiation, surface conduction and volumetric (microwave) heating. The involved critical parameters are discussed comprehensively in the results such as the maximum operating temperature, the maximum sublimation pressure, the total drying time and the overall power consumption. The results show that at low aspect ratios in surface heating technique, the 3D model is mandatory due to the large deviation in the drying time, maximum temperature and maximum pressure with both 2D and 1D models. Comparison between the present model and previous experimental and numerical works has been executed and good agreement has been observed.