Abstract

The optimum condition for the sublimation process taking place in a porous half space are determined in this paper. The vapor mass concentration at the surface of the porous medium and the initial frozen mass concentration in the frozen region are predetermined. The optimum condition is found by determining the vapor mass concentration at the sublimation front between the vapor and frozen phases, that yields the maximum flux of the vapor mass at the sublimation front. Exact solutions of the temperature and vapor mass concentration as well as the location of the moving sublimation front are obtained. The surface temperature used as the thermal controller is also determined to match the optimum sublimation condition.

Issue Section:
Porous Media
Keywords:
porous materials, mass transfer, heat transfer, sublimation, temperature, Heat Transfer, Moving Boundaries, Phase Change, Porous Media
Topics:
Porous materials, Temperature, Vapors, Heat transfer
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Copyright © 2002
 by ASME
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