Transverse permeability in Eucalyptus nitens wood specimens

Permeability functionalities are noticeable in the wood drying and impregnation processes because it has an effect on the bulk flow of a fluid through the wood structure. The aim of this work was to measure the radial and tangential specific gas permeability of Eucalyptus nitens wood for 10 different provenances. Furthermore, the effect of the radial position (defined as inner-wood, middle-wood, and outer-wood) on the measurements was investigated. The specific gas permeability of E. nitens ranged in order of magnitude from 10(-20) to 10(-16) m(2). The results showed that the radial position had a statistically significant effect on the specific permeability in both flow directions and, in general, the permeability values increased from inner-wood to outer-wood. Moreover, the scanning electron microscopy images showed obstruction of vessels by tyloses which explained the lower permeability values obtained in the inner-wood of E. nitens. Differences in the magnitude of the permeability values could explain the diverse drying and impregnation behavior according to the wood zones, the low permeability values in the internal wood-zone could suggest an opportunity for improving it, through chemical modification or structural changes to introduce new functionalities of this radial wood-zone in Eucalyptus nitens.

Automated summary

Permeability functionalities play an important role in wood drying and impregnation processes. In this study, the radial and tangential specific gas permeability of Eucalyptus nitens wood from 10 different provenances were measured. The results showed that the radial position had a significant effect on permeability, with values increasing from inner-wood to outer-wood. Scanning electron microscopy images revealed vessel obstruction by tyloses in the inner-wood, explaining the lower permeability values. This study suggests an opportunity for improving the permeability of the inner-wood through chemical modification or structural changes.