摘要
以二氧化硅气凝胶粉体为研究对象,基于其微观结构研究了内部纳米骨架及纳米孔洞的气固耦合热导率。在考虑二氧化硅气凝胶颗粒堆积的情况下,建立了微米孔径分布的气固耦合传热模型。结合单个二氧化硅气凝胶颗粒的热导率,并考虑了辐射传热对二氧化硅气凝胶粉体热导率的影响,推导出了计算二氧化硅气凝胶粉体纳米孔与微米孔并存的双孔径分布情况的等效热导率表达式。把模型计算结果与实验数据进行了比较,分析了粒径和环境压力对二氧化硅气凝胶粉体热导率的影响,结果显示,实验测量结果和模型计算结果有着相同的趋势,但模型计算值要略低于实验测量值。
The gas-solid coupling thermal conductivity of internal nano-skeleton and nano-voids was studied based on the microstructure of silica aerogel powder.Considering the accumulation of aerogel particles,agas-solid coupled heat transfer model with micron pore size distribution was established.The thermal conductivity of single silica aerogel particle and the radiative thermal conductivity of silica aerogel powder were considered,as well as an equivalent thermal conductivity expression for calculating the dual pore size distribution of silica aerogel powder was derived.The calculated values of the model were compared with the experimental data,and the influence of particle size and ambient pressure on the thermal conductivity of the silica aerogel powder was analyzed.The experimental results show that the experimental results are similar to the results of the model calculation,but the calculated values of the model are slightly lower than the experimental values.
作者
陈光楠
冯梦梦
肖欢
史燕娟
石贵滨
何松
CHEN Guang-nan;FENG Meng-meng;XIAO Huan;SHI Yan-juan;SHI Gui-bin;HE Song(School of Safety Science and Emergency Management,Wuhan University of Technology,Wuhan 430070,China)
出处
《武汉理工大学学报》
CAS
北大核心
2019年第7期21-26,共6页
Journal of Wuhan University of Technology
基金
国家自然科学基金(51706165)
关键词
二氧化硅气凝胶粉体
热导率
双孔径分布
传热模型
silica aerogel powder
thermal conductivity
dual pore size distribution
heat transfer model
作者简介
陈光楠(1994-),男,硕士生.E-mail:996650490@qq.com;通讯作者:何松(1987-),男,博士,讲师.E-mail:hsong@whut.edu.cn
