Abstract: Freeze drying is an effective method to protect unearthed water-logged archaeological wooden artifacts after they are impregnated in polyethylene glycol solution.In this paper，the freeze drying experiments of simulated wooden artifact were carried out on a self-made apparatus.The diffusion coefficient of water vapor in the drying part was fitted according to the experimental data.For a slow cooling velocity of 0.4℃·min^-1，the diffusion coefficient was 1.13×10^-4m²·s^-1；for a quick velocity of 2.0℃·min^-1，the diffusion coefficient was 5.53×10^-5m²·s^-1.The result would offer help for the time prediction and control optimization of the freeze drying of archaeological wooden artifacts.

Key words: freeze drying, archaeological wooden artifacts, diffusion coefficient, water vapor

摘要： 采用聚乙二醇(PEG)溶液进行预处理，然后加以冷冻干燥，是保护出土饱水木质文物的有效方法。在自制的冷冻干燥装置上进行了仿木质文物的冻干实验，根据实验数据拟合得到了干燥区的水蒸气扩散系数。该数据将为文物冻干过程的时间预测和控制优化提供帮助。

关键词: 冷冻干燥, 木质文物, 扩散系数, 水蒸气