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Technical Report

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Heat transfer, moisture transfer, glass beads


The Irreversible Thermodynamics-based model for the description of coupled heat and moisture transfer, attributed to Cary and Taylor, was analyzed. The transport coefficients appearing in the model equations were independently determined, and the equations were numerically integrated to predict temperature and moisture content profiles for a closed system of water unsaturated glass beads. An experimental investigation of the moist glass beads medium provided measurements of steady-state profiles of local temperatures and moisture content. These data, when compared with model predictions, indicated the validity of the Irreversible Thermodynamics approach. The coupling coefficient relating thermal gradients to moisture flux was found to be strongly moisture-dependent. The coupling coefficient which relates moisture content gradient to heat flux was found to be extremely small, and the heat flux associated with the moisture content gradient proved to be negligible.


In Cooperation with Engineering Experiment Station Pub no.29

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