Bekhta Pavlo, Ozarkiv Igor, Alavi Saman, Hiziroglu Salim
Department of Wood Composite Material Technology, Ukrainian State University of Forestry and Wood Technology, Lviv.
Bioresour Technol. 2006 Sep;97(13):1572-7. doi: 10.1016/j.biortech.2005.06.005. Epub 2005 Aug 8.
An analytical expression for the drying time of thin lumber is derived, based on a method presented in this study. The laws of moisture content change in wood as function of mass transfer are used for the theoretical approach. The diffusion equation for moisture content is set up for a three-dimensional block of lumber based on the assumption of uniform initial distribution of moisture throughout the specimen. The boundary condition stipulates that the moisture gradient at the boundary is proportional to the deviation of the moisture content of the slab from the equilibrium value at that temperature. These conditions are used to derive an analytical expression for the time required to get from an initial moisture distribution to a desired final moisture content of thin lumber. For a sample calculation, the result of drying time agrees within 10% with the prediction of previously published analytical formulas for the drying curve.
基于本研究提出的一种方法，推导出了薄木材干燥时间的解析表达式。在理论分析中采用了木材中水分含量随传质变化的规律。基于整个试件水分均匀初始分布的假设，建立了一个三维木材块的水分扩散方程。边界条件规定，边界处的水分梯度与板材在该温度下的水分含量与平衡值的偏差成正比。利用这些条件推导出了薄木材从初始水分分布达到所需最终水分含量所需时间的解析表达式。对于一个示例计算，干燥时间的结果与先前发表的干燥曲线解析公式的预测结果在10%以内相符。
