Numerical model of freeze drying of random solids at two-region conductive-radiative heating

A novel one-dimensional two-region plane moving boundary problem (PLMBP) in vacuum freeze-drying for combination of different boundary conditions on fixed dried and frozen regions boundaries, was formulated. The internal resistance of mass transfer in dried region which causes unknown a priori temperature of sublimation T-s(t) and mass concentration of water vapour C-s(t) at moving ice front was taken into account. Numerical model equations in the plane geometry were solved with the MacCormack predictor-corrector method which is finite differences method of second order accuracy. Simulation of the proposed model enables determination of optimal control characteristics of the vacuum freeze drying of random solids at intensive two-region contact-radiative heating.