Wood Sorption Fractality in the Hygroscopic Range. Part II. New Model Development and Validation

Authors

  • Bingye Hao
  • Stavros Avramidis

Keywords:

Water, sorption, isotherm, fractal dimension, internal surface

Abstract

The sorption isotherms of mature sapwood and heartwood from two softwood species were obtained experimentally. The data were used for the determination of how their fractal values change with an increase in moisture content using the Hao-Avramidis model developed in the past, and for the substantiation of a new fractal polynomial sorption equation based mainly on the fractal parameter D, assuming D being the dominant control parameter of sorption at higher sorption regions. The new sorption theory considered both the molecular layering stage at low humidities and the non-layering or fractal sorption stages at high humidities. Its good curve-fitting behavior justified the assumption that the state dynamics of the sorbed water were stepwise or locative instead of smooth, and three or four steps were identified.

References

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Published

2007-06-05

Issue

Number 4 / October 2003

Section

Research Contributions

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