Temperature Effect on Diffusion Coeficient in Drying Wood
Keywords:
Wood drying, drying temperature, moisture diffusion, activation energy, simulationAbstract
The effect of drying temperature on unsteady-state moisture diffusion was studied by drying small, nearly green. 25-mm-thick specimens of yellow-poplar (Liriodendron tulipifera L.) and red oak (Quercus sp.) at four temperatures (32.2, 43.3, 54.4, and 65.6°) and at two successive equilibrium moisture contents (10 and 5% EMC). That the moisture diffusion through wood is an activated process was indicated by the fact that the plots of the logarithm of diffusion coefficient versus the reciprocal of absolute temperarature were largely linear. However, the calculated activation energies (4195 cal/mol for yellow-poplar, 6166 cal/mol for red oak when dried to 10% EMC) differed greatly, were of low magnitude, and were possibly related to the specific gravity of the wood.References
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