中文摘要：

采用3种扩散偏微分方程求解方法研究了落叶松干燥结合水扩散系数；分析不同干燥介质条件下，10mm、20mm厚落叶松板材的一维径向非稳态扩散试验数据，确定干燥动力学曲线；对不同求解方法的水分扩散系数进行比较分析，研究干燥介质温度、湿度、试件厚度、含水率阶段等因素对水分扩散系数的影响机制。结果表明：在特定的环境湿度条件下，扩散系数随温度升高而增大，在3种分析求解方法中，Crank方法的扩散系数与温度间具有的线性关系最为显著；在温度为80℃的干燥试验中，随平衡含水率（EMC）降低，3种方法的扩散系数均呈现出显著增大趋势；相同干燥介质条件下，厚度为20mm试件的扩散系数均明显高于10mm试件扩散系数，这种趋势随温度的升高而愈显突出；纤维饱和点以下，木材结合水扩散系数随含水率降低呈指数规律降低。

英文摘要：

In order to explore moisture transfer law during larch timber drying process, three major diffusion PDE solution methods were used to analyze bound water transfer. One dimensional redial unsteady diffusion experiments for larch timber specimens with thickness of 10 mm and 20 mm were conducted. The parameters for drying kinetics curves were determined. Three kinds of analytical solutions for diffusion differential equation were obtained. The diffusion coefficients data of different solution procedures were compared. The influence mechanism of technique factors and material characters on moisture diffusion were determined. The results showed that under 50%-55% relative humidity, conditions, diffusion coefficients increased with temperature increasing. Among the three solution procedures, the linear function relationships between diffusion coefficients and experimental temperatures of Stamm ＇ s method is the most notable one. In drying experiments with temperature of 80℃ , when the equilibrium moisture content （EMC） decreased, the diffusion coefficients increased greatly for all three solution methods. Under the same drying conditions, diffusion coefficients of 20 mm specimens are all bigger than those of the 10 mm specimens＇ for three solution methods. This change trend became even more remarkable with the temperature increasing. Below FSP, drying diffusion coefficients decreased exponentially with wood initial moisture content decreasing. It was coincided with basic descriptions of the wood bound water activation energy theory.