Water vapor sorption is fundamental to the behavior of wood and affects nearly all its properties. The relation between equilibrium moisture content of the wood and relative humidity at a given temperature is described by the water vapor sorption isotherm. For a century this has been a central part of wood science, and for nearly as long, the scientific discussion has focused on the fundamental mechanisms governing the wood-water equilibrium state and the sorption process towards this state. Sorption isotherm models are often used to understand the interactions of water with wood. While based on idealized physical systems, these models are used to predict actual physical properties of wood. Given the complexity of the wood-water equilibrium state, we hypothesize that the most common sorption isotherm models are unable to describe water in wood, despite their popularity and widespread use to do exactly that.
Keywords: Sorption isotherm, model, Hail-wood-Horrobin, GAB, Dent, BET
Authors
Emil Engelund Thybring
University of Copenhagen, IGN, Rolighedsvej 23, DK-1958 Frederiksberg C, Denmark
Charles R. Boardman
Forest Products Laboratory, Building and Fire Sciences, 1 Gifford Pinchot Drive, Madison, WI 53726, United States
Samuel L. Zelinka
Forest Products Laboratory, Building and Fire Sciences, 1 Gifford Pinchot Drive, Madison, WI 53726, United States
Samuel V. Glass
Forest Products Laboratory, Building and Fire Sciences, 1 Gifford Pinchot Drive, Madison, WI 53726, United States
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