Measuring Dependence of Diffusion Coefficient of Wood on Moisture Concentration by Adsorption Experiments


  • William T. Simpson


<i>Populus sp.</i>, seasoning, prediction, finite difference technique


The dependence of the diffusion coefficient on moisture concentration of aspen wood at 110 F was determined by using an experimental method that requires a series of adsorption experiments and by applying a numerical method that includes using a finite difference technique to solve the diffusion equation with a diffusion coefficient that is dependent on concentration. The analysis showed that the diffusion coefficient increases with mosture content. Between 2.5 and 18.0% moisture content, the diffusion coefficient increases by a factor of 8.


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