Effect of wetwood and blue stain (Ceratocystis spp.) on the drying rate and fluid transport coefficients of poplar (P. nigra)

In this research، the effect of wetwood and blue stain on the drying rate and fluid transport coefficients of poplar (P. nigra) was evaluated. For this purpose، five boards with dimensions of 150 × 35 × 45 mm were cut from wet wood، normal wood and stained -wood areas of freshly cut lumbers in Taleghan region and then dried to the final moisture content of 8 percent inside a laboratory dryer at temperature of 50 °C، relative humidity of 60% and air velocity of 1 m/s. Overall، drying time was 120 h. After drying، the transverse permeability and diffusion coefficients were measured. The results showed that the wetwood had no decreasing effect on the drying rate of poplar wood; however، it reached to the final moisture content slower due to higher initial moisture content. Also، the wetwood had no significant effect on the transverse permeability but reduced the diffusion coefficient. In contrast to the wetwood effects، the drying rate، permeability and diffusion coefficients were increased due to the blue stain.