摘要
多孔泡沫是一类低密度、高比表面积、具有独特性能的新型功能材料。实际多孔泡沫材料通常是非均质的,即其孔隙结构分布是随机的。为研究非均质多孔泡沫材料的导热性能,提出用孔隙均匀度作为表征孔隙结构分布随机性的参数,以多孔石墨泡沫为例,分析孔隙均匀度对多孔泡沫有效热导率的影响。数值计算结果表明:孔隙结构分布越不均匀,多孔泡沫材料的导热性能越差。根据计算结果提出了非均质石墨泡沫相对有效热导率的预测式,并与现有文献报道的结果进行了比较,发现当前结果呈现了孔隙结构随机性对材料有效热导率的影响,与ORNL实验结果更吻合。
Porous foam is a novel functional material, which have low density, high specific surtace area ana particular performance. However, porous foam is always heterogeneous, the distribution of pore structure is random. In this study, a random parameter, pore uniformity U, is proposed to study the thermal conductivity of heterogeneous porous foam and analyze the influence of pore uniformity on its effective thermal conductivity based on graphite foam. Numerical results show that the thermal conductivity of porous foam material decreases with the increase of the randomness of pore structure. A relationship between pore uniformity, porosity and thermal conductivity of heterogeneous graphite foam is proposed and compared with those in literature. The present results are in reasonable agreement with the measured data of ORNL and reflect the influence of pore structures.
出处
《化工学报》
EI
CAS
CSCD
北大核心
2014年第3期879-883,共5页
CIESC Journal
基金
重庆市科技攻关计划项目(81826)
'211工程'三期建设项目(S-09101)
中央高校基本科研业务费资助项目(CDJXS11140014)~~
关键词
多孔介质
随机结构
孔隙均匀度
有效热导率
热传导
数值模拟
porous medium
stochastic structure
pore uniformity
effective thermal conductivity
heat conduction
numerical simulation
作者简介
张新铭（1953－），男，教授。
