Computation of Temperature Conductivity of Frozen Wood during its defrosting

An approach for the computation of the temperature conductivity of frozen wood during its defrosting has been suggested. The approach takes into account the physics of the processes of melting of both the frozen bound and free water in the wood in respective temperature ranges. It refl ects for the fi rst time also the infl uence of the fi ber saturation point and of the volume shrinkage of each wood species on its temperature conductivity coeffi cient in frozen state. In the present paper, the suggested approach for the computation of the temperature conductivity of poplar, spruce, beech, oak, walnut and acacia in the temperature range between -60 C and -1 C is used. It is determined that the temperature conductivity of wood, during melting of frozen bound water in it, is up to some tens of times larger than the temperature conductivity of wood during melting of frozen free water in it. The obtained results can be used both for technological and other engineering calculations and analysis of processes of thermal and hydrothermal treatment of wood materials, as well as in software of systems for model based automatic control of such treatment.