Exact solution of coupled heat and mass transfer with double moving interfaces in a porous half-space. Part 1: Mass transfer controlled by the fick law

Coupled heat and mass transfer with double moving interfaces, taking place in a porous half-space, is defined, and exact solutions for the temperature and moisture distributions as well as the positions of the two moving fronts are obtained. The effects of the ratio of the thermal diffusivity in the sublimated region to that in the frozen region, the ratio of the steady heat flux in the frozen region to that in the sublimated region with the same heat conduction distance, the ratio of the steady heat flux in the desorbed region to that in the sublimated region, and the volume fractions of the free water and absorbed water in the pore of the porous body on the sublimation and desorption are analysed. Conclusions are drawn on the basis of the results.