Isothermal Moisture Transfer Coefficients in <i>Pinus Radiata</i> Above the Fiber-Saturation Point, Using the Moment Method

Authors

  • M. J. Cunningham
  • R. B. Keey
  • C. Kerdemelidis

Keywords:

diffusion, Pinus radiata, moisture transport, water potential, transport coefficients, wood, construction moisture, fiber-saturation, capillarity, moment method

Abstract

The "moment method" was used to measure the transfer coefficients for moisture movement above fiber-saturation in Pinus radiata under isothermal conditions using moisture concentration as the driving force. Measurements were made at 5 C, 17 C and 30 C, and in the longitudinal, radial and tangential directions. Results obtained lie between 1.6 x 10-10 m2/s and 1.24 x 10-7 m2/s. Despite scatter in the results, certain important trends are detectable, viz: (1) there is roughly an order of magnitude difference between the longitudinal results, and the results in the radial and tangential directions at 30 C; (2) there is an apparent increase in transfer rate as the temperature rises; (3) the transfer coefficient tends to increase with moisture content for most results.

References

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Published

2007-06-22

Issue

Number 2 / April 1989

Section

Research Contributions

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