文档介绍：中国工程热物理学会传热传质学
学术会议论文编号:123116
水分含量对颗粒型含湿多孔介质导热系数的影响及机理
陈汉翠1,胡爱娟1,2,田猛山1,郭庆亮1,于明志1,2
(,山东济南 250101;,山东济南 250101)
(Tel: **********; Email: chcdd19881217@)
摘要:本文用玻璃珠模拟堆积型多孔介质,用Hotdisk热常数分析仪对不同含湿率下玻璃珠堆积颗粒的导热系数进行测量,D结合体式显微镜观察不同含湿率下试样孔隙内的水分形态及颗粒聚集状态,研究分析水分含量、水分形态,颗粒聚集状态对堆积型多孔介质导热系数的影响及机理。实验结果表明:试样的导热系数随含湿率的增大呈非单调递增趋势。不同含湿率下堆积型多孔介质孔隙内水分形态不同,其对颗粒的作用不同,颗粒间出现聚集,从而导致颗粒间距离发生变化,进而表观体积变化。水分含量、水分形态、颗粒间间距的变化均会影响介质的导热系数大小,介质导热系数的变化趋势是由这些影响因素综合决定的。
关键词:多孔介质;含湿率;颗粒聚集;导热系数
The influence mechanism of moisture content on thermal conductivity of unsaturated wet porous medium
Chen Hancui1,Hu Aijuan1,2,Tian Mengshan1,Guo Qingliang1,Yu Mingzhi1,2
( of Thermal Engineering, Shandong Jianzhu University, Jinan 250101,China;2 Key Laboratory of Renewable Energy Utilization Technology in Building , Ministry of Education, Jinan 250101, China)
Abstract:A hotdisk thermal constant analyzer is used to measure thermal conductivity of porous media, unconsolidated glass beads, and bined with a stereo microscope to observe the water morphology and particle aggregation state in sample with different moisture contents. The experimental results show that: the thermal conductivity of sample non-monotonically increases with moisture content increasing. Different water morphologies exist in pores of unconsolidated porous medium with different moisture contents