LTRANSFORMATION RELATIONS AND MATRIX IMPLEMENTATION OF MULTIPHYSICS MODEL FOR TEMPERATURE AND MOISTURE FIELDS IN WOOD

摘要

This paper deals with the numerical simulation of 3D heat and moisture transfer in wood. The appropriate mathematical model is based on a set of coupled heat and mass transfer equations.The main contributions of this paper are: first, the transformation relations between matrixes of material coefficients (diffusion and thermal conductivity coefficients) in anatomical and geometrical directions in three-dimensional case; second, the implementation of a numerical solution for the three-dimensional problem of nonisothermal moisture transfer in the anisotropic structure of wood in convective drying with transient phenomena (Soret effect, Duffour effect).The simulation is based on the unsteady-state nonisothermal nonlinear diffusion of moisture and heat with respect to the orthotropic nature of wood. It deals with a transport model which makes use of the gradient of moisture and temperature for motive power and respects the dependence of material coefficients on temperature and moisture.