plane problem of heat conduction

In the presented study, the mathematical model for drying the porous timber beam of a circular cross-section under the action of a convective-heat nonstationary flow of the drying agent is constructed.  When solving the problem, a capillary-porous structure of the beam is described in terms of a quasi-homogeneous medium with effective coefficients, which are chosen so that the solution in a homogeneous medium coincides with the solution in the porous medium.  The influence of the porous structure is taken into account by introducing into the Stefan–Maxwell equation the effective binary inte