基于容积密度计算的X射线法测定木材含水率分布

doi:10.11707/j.1001-7488.20140119

Abstract

Abstract:

A new algorithm for calculating moisture content (MC) by X-ray scanning was deduced and studied in this paper. Firstly, the principle of the X-ray measuring wood density was presented. Secondly, the volume density of wood components(cell wall material and water)under volume change were quantitatively analyzed based on the concept of volume density in the porous materials. And then the formulas for calculating the MC were deduced with the fiber saturation point (FSP) as demarcation line. Finally, taking Chinese fir(Cunninghamia lanceolata)as the experimental material, the density variation with drying time was measured by X-ray scanning during wood drying process. Based on these data, the MC distribution was calculated by Cai method and volume density method, at the same time, taking slicing method as control group, the results from this three method were compared. The results showed that there were no significant differences between volume density method and slicing method in the entire range of MC. When MC was above FSP, the MC distribution based on Cai method was significantly different with the slicing method, when MC was lower than FSP, there were no significant differences between these two methods. It was suggested that the volume density method was reasonable, which could provide an accurate method for calculating MC distribution during wood drying via X-ray scanning method.

Key words: volume density, X-ray scanning method, Cai method, slicing method, moisture content distribution

CLC Number:

S781

Hao Xiaofeng, Lü Jianxiong, Yu Changming, Jiang Jiali, Jiang Jinghui. Moisture Content Distribution of Wood via X-Ray Method Based on the Volume Density[J]. Scientia Silvae Sinicae, 2014, 50(1): 125-132.

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Moisture Content Distribution of Wood via X-Ray Method Based on the Volume Density

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