多孔介质浸湿过程水分迁移的微CT分析  

Analysis of water migration in porous material using micro-CT during wetting

作　　者：吴迪[1] 彭晓峰[1] 

机构地区：[1]清华大学相变与界面传递现象实验室,北京100084

出　　处：《热科学与技术》2006年第2期122-126,共5页Journal of Thermal Science and Technology

基　　金：国家自然科学基金重点项目支持(50136020)

摘　　要：以木材为对象,针对浸泡水的过程,利用CT成像、结构重构及灰度值分析技术进行孔隙内水分动态迁移过程的实验观察与分析。水分浸入可分为三个阶段:第一阶段,浸入孔密区,且在一定量的浸水范围内,水分会保持在孔密区不会浸入孔疏区;第二阶段,突破孔密区,到达孔疏区,很快在孔疏区的水分聚集超过孔密区,孔密区内形成一条非饱和带;第三阶段,更多水分浸入时,孔疏区先达到饱和状态,水分不断向孔密区施压,最终浸湿非饱和带。Experiments were conducted to observe water migration in a wood during wetting using a micro CT （scanning analysis technology）. Water transport in a wood immersed in water can be divided in three stages. At the beginning, the dense region of the wood is wetted and contains a little amount of water which is unable to transfer into the sparse region, as a result of the larger capillary force of the dense region. Secondly, as much water got into the wood, water diffuses to sparse region from the dense region, and soon the water in the sparse region is much more than that in the dense region. Thirdly the sparse region first reaches the saturation with water, and then water is put into the unsaturated dense region by the pressure of the water in sparse regions surrounding it.

关 键 词：CT 多孔介质 浸湿 水分迁移 

分 类 号：TK124[动力工程及工程热物理—工程热物理]