A THEORETICAL AND EXPERIMENTAL INVESTIGATION OF THE CONVECTIVE DRYINGOF AUSTRALIAN PINUS-RADIATA TIMBER

A series of experiments on the convective drying of Pinus radiata has been undertaken at the CSIRO Division of Forest Products in Australia. This paper uses the experimental results to compare predictions from both a comprehensive mathematical model, which includes wood temperatu re, moisture content and pressure distributions, and a simplified mode l (two versions) which assumes constant total pressure. From the simul ations, it is seen that both models adequately predict the overall kin etics of the wood drying process. For a complete understanding of the heat and mass transfer phenomena that occur in wood during drying the comprehensive model is necessary. However, it is computationally long and expensive, and as such, does not suit the practical drying needs o f the timber industry in Australia. Consequently, the simplified model , which has acceptable computation time and sufficient accuracy for en gineering purposes, enables the wood drying process to be optimised fr om both performance and economic perspectives.