Description of moisture dependence of diffusion coefficient by moisture diffusion equation considering Coulomb friction

摘要

The diffusion model based on Fick's second law has been sued to predict the moisture movement in nonsteady state However, the diffusion coefficient generally is not a constant. The Diffusion equation origins from well-known heat transfer theory. In the case of moisture movement, moisture below fiber Saturation point should be considered to have some interaction With wood substances. Therefore some additional friction seems To be added to the diffusion process.