Thermal conductivity measurements on wood materials with transient plane source technique

• Mathematical derivation of the equation of the Hot-Disk for anisotropic materials.
• Hot-Disk technique for the thermal characterization of Italian tree species.
• Axial thermal conductivity resulted higher than radial thermal conductivity in wood.

The conductive heat flux can be modeled by a vector: in a real anisotropic material, the contribution of each directional components is not easy to measure. The transient plane source technique, also known as Hot-Disk, stands as a valid device for the measurement of thermal diffusivity in this kind of materials if some geometric requirements are met for the preparation of the samples. In this paper, the theoretical derivation of the equation ruling the computation of the thermal diffusivity and conductivity in anisotropic material using the Hot-Disk device is presented and used for obtaining these properties for three tree species from the Northeast of Italy: oak, spruce and larch.