Predicting Average Moisture Content of Wood in a Changing Environment
Keywords:
<i>Picea engelmaunii</i>, <i>Tsuga heterophylla</i>, <i>Populus grandidentata</i>, <i>P. deltoides</i>, <i>Prunas serotina</i>, <i>Acer rubrum</i>, <i>Ulmus americana</i>, <i>Quercus alba</i>, <i>Q. rubra</i>, moisture gradients, diffusion coefficients, equilibrium moisture content, relative vapor pressure, vapor diffusion, vapor pressureAbstract
In the past, predicting the behavior of wood exposed to a variable temperature and humidity environment was based on experience. However, with recent advances in solving complicated heat and mass transfer problems with the digital computer, prediction of the behavior of wood exposed to a variable temperature and humidity environment has become possible.
This report examines several of the factors that influence wood's behavior and gives some simplifications necessary to formulate an adequate model of moisture movement in wood. A series of experiments was conducted to measure moisture content of wood in a changing temperature and humidity environment. These measurements were compared with the results predicted from the model using a digital computer. The model was adequate for predicting the moisture response of the samples used in these experiments.
References
Bird, R. B., W. E. Stewart, and E. N. Lightfoot. 1960. Transport phenomena. John Wiley and Sons, Inc., New York. 780 pp.nCrank, John. 1956. The mathematics of diffusion. Clarendon Press, Oxford.nDjolani, B. 1970. Hysteresis and secondary phenomena in sorption of water in wood. Dep. Exploit Util. Bois, Laval Univ. Res. Note 8. Laval University, Quebec. 35 pp.nHedlin, C. P. 1969. Relative humidities for Douglas-fir wood between 10° and 70° F. Wood Sci.2(2):125-128A.nKoehler, A. 1941. Relation of moisture content and drying rate of wood to humidity atmosphere. Monograph No. R 509. For. Prod. Lab., Madison, Wis. 11 pp.nKubler, H. 1957. Studies on the movement of moisture through wood. Holz Roh- Werkst.15(11):453-468.nMcNamara, W. S. 1969. Effects of stress on the diffusion of moisture in wood. PhD thesis. Dep. of Wood and Pap. Sci., North Carolina State Univ., Raleigh. 102 pp.nMoschler, W. W., and R. E. Martin. 1968. Diffusion equation solutions in experimental wood drying. Wood Sci.1(1):47-57.nSpalt, H. A. 1958. Fundamentals of water vapor sorption by wood. For. Prod. J.8(10):288-290.nStamm, A. J. 1962. Wood and cellulose-liquid relationships. N. C. Agric. Exp. Sta. Bull. 150. Raleigh, N.C. 56 pp.nU.S. Forest Products Laboratory. 1974. Wood Handbook: Wood as an engineering material. U.S. Dep. Agric. Handb. 72. 528 pp.nWirakusumach, S. 1962. Comparison between the experimental and theoretical drying diffusion coefficients for softwoods and hardwoods. M.S. thesis. Dep. of Wood and Pap. Sci., North Carolina State Univ., Raleigh.n
Downloads
Published
Issue
Section
License
The copyright of an article published in Wood and Fiber Science is transferred to the Society of Wood Science and Technology (for U. S. Government employees: to the extent transferable), effective if and when the article is accepted for publication. This transfer grants the Society of Wood Science and Technology permission to republish all or any part of the article in any form, e.g., reprints for sale, microfiche, proceedings, etc. However, the authors reserve the following as set forth in the Copyright Law:
1. All proprietary rights other than copyright, such as patent rights.
2. The right to grant or refuse permission to third parties to republish all or part of the article or translations thereof. In the case of whole articles, such third parties must obtain Society of Wood Science and Technology written permission as well. However, the Society may grant rights with respect to Journal issues as a whole.
3. The right to use all or part of this article in future works of their own, such as lectures, press releases, reviews, text books, or reprint books.
