Using the inverse method to estimate the solar absorptivity and emissivity of wood exposed to the outdoor environment

This study used the inverse method to investigate the solar absorptivity and emissivity of wood. The solar absorptivity and emissivity estimates were 0.396 (0.308-0.570) and 0.526 (0.307-0.772), respectively. They were highly dependent on the boundary conditions of convective heat transfer coefficients. Emissivity was much lower than that seen in most previous studies. Absorptivity was closely related to the L*a*b* color system, mainly to whiteness. It increased with increasing density because lightness or whiteness has the highest correlation with density. There was a weak positive correlation between absorptivity and emissivity overall with R²=0.223.