Numerical modeling of sublimation heat and mass transfer with convective interface and temperature-dependent thermal properties

The sublimation process, which directly transforms solid materials into gaseous water vapor, is typically utilized with items of great value, particularly in the food and pharmaceutical industries, where it is feasible to have both significant investment in capital and operating expenses. In light of this, modeling of convection within the sublimated region as well as at the interface is carried out. The model accounts for temperature-dependent heat conductivity and mass diffusivity. In addition, a linear profile of the volumetric internal heat is assumed to improve the operating time with least energy consumption. The condition for limitation of sublimation is derived for full nonlinear model. It is shown that sublimation can only take place in the region under the sublimation limit curve. The current model is solved by Legendre wavelet collocation technique. The correctness of the obtained results is verified with the results of finite-difference technique in the case of full nonlinear problem and found good acceptance. Moreover, results obtained from the current numerical approach show excellent acceptance with the analytical results of the linear model. It is found that temperature-dependent mass diffusivity enhances the concentration profile more than fixed mass diffusivity. With temperature-dependent heat conductivity, materials sublimate faster than usual.