The effect of drying intensity and moisture content on longitudinal permeability of poplar tension and normal wood (populus nigra )

The longitudinal gas permeability of tension wood and normal wood of Populus nigra dried by two different drying conditions was measured. Board specimens were dried under mild conditions (50ºC, and ٪63 relative humidity) to reach ٪11.8 MC, and under severe conditions (62ºC, and ٪35 RH) to reach ٪7 MC. After drying, dowel specimens of 14 mm in diameter and 40 mm length were prepared. Epoxy resin was applied all around each specimen to prevent fluid passing through lateral direction. Results showed that under both moisture conditions, longitudinal gas permeability values in normal wood were greater than those in tension wood. Furthermore, the permeability of both tension and normal wood decreased by increasing of drying intensity and decreasing of final moisture content