References(1) Cited-By(6) Freeze-drying of porous bodies (void is initially saturated with ice) by conductive heat transfer is carried out under pressures of 0.4-1.5mmHg. It is found from the experimental results that under some conditions plane sublimation becomes unstable and breaks into zone sublimation. The criterion of stability of plane sublimation is analysed and is found to depend on the physical properties of the porous bodies and on the drying conditions. By considering the instability of plane sublimation a model of freeze-drying is proposed. The numerical results by this model are in relatively good accord with experiment.
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