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Journal of Wood Science

Official Journal of the Japan Wood Research Society

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Liquid water diffusivity of wood from the capillary pressure-moisture relation

Journal of Wood Science volume 55, pages 91–99 (2009)Cite this article

Abstract

This study focuses on liquid water transport in wood above the fiber saturation point in the nonhygroscopic region. The liquid water transport of hygroscopic porous materials including wood is usually described by Darcy’s law. It requires knowledge of capillarity and intrinsic and relative permeabilities. In this study, the capillary pressure-water relation and relative permeability were investigated using experimental data for wood available in the literature. The performance of three models (Brooks-Corey model, van Genuchten model, and Durner’s bimodal pore-size distribution model) was investigated for the capillary pressure-water relation. These models have advantages in that each shape parameter has qualitative physical meaning for the pore-size distribution. Most species had unimodal pore distributions except for aspen, which had a bimodal pore distribution. The van Genuchten model represented the capillary pressure-water relation better than the Brooks-Corey model. Durner’s bimodal model was found to be the most appropriate for the capillary pressure-moisture relation of aspen. The relative permeability was calculated by using Mualem’s model, which was compared with the value from the Couture model. From the results, the liquid water diffusivity divided by intrinsic permeability of wood was estimated. This approach may be promising for adopting the liquid water diffusivity for the numerical simulation of drying and sorption, although there might be considerable variation within and between trees.

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Authors and Affiliations

  1. Department of Wood Science and Engineering, Division of Forest Resources and Landscape Architecture, Chonnam National University, Gwangju, 500-757, Republic of Korea

    Wook Kang & Woo Yang Chung

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  1. Wook Kang
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  2. Woo Yang Chung
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Correspondence to Wook Kang.

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Kang, W., Chung, W.Y. Liquid water diffusivity of wood from the capillary pressure-moisture relation. J Wood Sci 55, 91–99 (2009). https://doi.org/10.1007/s10086-008-1009-x

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