Determination of diffusion coefficients for sub-alpine fir

Abstract

Estimates of the drying rate for sub-alpine fir lumber and the effect of process variables on final moisture contents are valuable information for kiln operators. The diffusion approach offers one generalized way to estimate the drying time required and the final moisture content distribution. The diffusion coefficients of normal wood and wet wood of sub-alpine fir lumber were determined by two types of approaches in this study: the traditional method and the inverse moisture diffusion algorithm. The results from both approaches indicate that the diffusion coefficient of normal wood is greater than that of wet wood for sub-alpine fir.