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Journal of Wood Science

, Volume 52, Issue 3, pp 195–201 | Cite as

Local water vapor diffusion coefficient when drying Norway spruce sapwood

  • Jonas Danvind
  • Mats EkevadEmail author
Original Article

Abstract

In this article, a one-dimensional and a two-dimensional approach to the evaluation of local diffusion coefficients for Norway spruce sapwood from measured moisture content (MC) values are presented. A studied wood sample was dried from the initial green condition to about 15% mean MC, but here only the diffusive part of the drying process between approximately 25% and 15% mean MC was treated. Measured local MC values were based on nondestructive X-ray computed tomography data. Finite element calculations were performed with two alternative diffusion coefficients to test the appropriateness of the diffusion coefficients that were evaluated from the measured MC values. The evaluated diffusion coefficients show interesting dependence on MC and distance from the evaporation surface. The advantage of using the methods presented is that the diffusion coefficient is calculated on a local level without having to define a function for the diffusion coefficient’s dependency on other parameters.

Key words

Wood FEM Drying Diffusion coefficient Computed tomography 

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Copyright information

© The Japan Wood Research Society 2006

Authors and Affiliations

  1. 1.Division of Wood Technology, Skellefteå CampusLuleå University of TechnologySkellefteåSweden
  2. 2.SkellefteåSweden

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