A Model to Explain "Anomalous" Moisture Sorption in Wood Under Step Function Driving Forces
Keywords:Diffusion, water vapor, cell walls, adsorption, non-Fickian behavior
AbstractIt has been hypothesized that "anomalous" transient moisture sorption in wood at high relative humidities is due to slow sorption of moisture in the cell walls. A mathematical model describing this phenomenon has been developed, which fits well the two-stage sorption (Fickian and non-Fickian) visible in experimental data and uses parameters with clear physical meaning. The values of these parameters can be derived by simple means. Thickness effects and other non-Fickian behavior are examined.
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