摘要
作为真空绝热板的芯材,多孔介质微尺度空间形貌结构及物性参数对其绝热性能影响较大。为研究多孔介质真空下的导热性能,选择颗粒状、纤维状和泡沫状3种典型多孔介质材料,并基于Lattice-Boltzmann(LBM)提出了一种随机构造多孔介质物理模型的方法。模型中重要参数结合多孔介质电镜扫描图像处理获取。采用D3Q15LBM模型进行数值模拟,并分析了真空度及颗粒/纤维/泡孔等效直径对导热系数的影响规律。模拟与实验的对比结果揭示了多孔介质真空下的导热系数随真空度及多孔介质物性参数的变化规律。
As the core material of the vacuum insulation panel, micro structure and physical properties of porous materials have great influence on the thermal insulation performance. To study the thermal conductivity of porous material under vacuum condition, three typical porous materials, that is, granular, fibrous and foamy materials are involved in this paper, and a physical model based on the Lattice-Boltzmann method （LBM） is proposed. The key parameters of the model are obtained by scanning electron microscope image from real porous materials. Numerical simulation and analysis are made to study the influence of the vacuum degree and the equivalent diameter of the particles/fiber/cell hole versus thermal conductivity by D3Q15 model based on LBM. Comparison of simulation and experimental results explores the principles of the thermal conductivity variation versus physical properties and vacuum degree. The work is significant to optimize the structure of core materials and to improve the accuracy of effective thermal conductivity prediction.
作者
阚安康
吴亦农
徐志峰
张安阔
王为
KAN Ankang WU Yinong XU Zhifeng ZHANG Ankuo WANG Wei(Shanghai Institute of Technical Physics, Chinese Academy of Science, Shanghai, 200083, China Merchant Marine College, Shanghai Maritime University, Shanghai, 201306, China)
出处
《南京航空航天大学学报》
EI
CAS
CSCD
北大核心
2017年第1期17-23,共7页
Journal of Nanjing University of Aeronautics & Astronautics
基金
中国博士后科学基金(2016M590385)资助项目
上海市自然科学基金(15ZR1419900)资助项目
