硬木中流体移动的双尺度多孔机理的依据(Ⅱ)描述实验结果的双尺度计算模型

编号 zgly0000342540

文献类型 期刊论文

文献题名 硬木中流体移动的双尺度多孔机理的依据(Ⅱ)描述实验结果的双尺度计算模型

学科分类 220.5550;木材加工与人造板工艺学

作者 PatrickPERRE 

作者单位 LERMAB-UMRINRA/ENGREF/UHP1093  ENGREF-INRA-14  rueGirardet54042NancyCedex  France 

母体文献 Chinese Journal of Chemical Engineering;中国化学工程学报: 英文版 

年卷期 2004,12(6)

页码 783-791

年份 2004 

分类号 TS652 

关键词 木材加工  硬木  流体移动  双尺度多孔机理  双尺度计算模型  实验研究 

文摘内容 The second part of this paper is devoted to the computational modelling of transient water migration in hardwood. During re-saturation, the moisture content, measured during the process by using X-ray attenuation (see part 1 of this paper), increases quickly very close to the cavity, but requires a very long time for the remaining part of the sample to absorb the moisture in wetting. For this configuration and this material, the macroscopic approach fails. Consequently, a dual-porosity approach is proposed. The computational domain uses a 2-D axisymmetric configuration for which the axial coordinate represents the macroscopic longitudinal direction of the sample whereas the radial coordinate allows the slow migration from each active vessel towards the fibre zone to be considered. The latter is a microscopic space variable. The moisture content field evolution depicts clearly the dual scale mechanisms:a very fast longitudinal migration in the vessel followed by a slow migration from the vessel towards the fibre zone.The macroscopic moisture content field resulting from this dual scale mechanism is in quite good agreement with the experimental data。