文献类型：期刊文献

英文题名：Thermal conductivity of nanoporous phenolic matrices: Measurements and predictions

作者：Zhou, Xiaoyi[1];Zhang, Tao[1];Fang, Fang[2];Zhang, Yupeng[2];Quan, Dongliang[2];Pan, Helin[1];Zhang, Yayun[1,3];Niu, Bo[1,3];Long, Donghui[1,3]

机构：[1]East China Univ Sci & Technol, State Key Lab Chem Engn, Shanghai 200237, Peoples R China;[2]HIWING Technol Acad, Innovat & Res Inst, Beijing 100074, Peoples R China;[3]East China Univ Sci & Technol, Key Lab Specially Funct Mat & Related Technol, Shanghai 200237, Peoples R China

年份：2024

卷号：197

外文期刊名：INTERNATIONAL JOURNAL OF THERMAL SCIENCES

收录：;EI(收录号：20240215351500);WOS:【SCI-EXPANDED(收录号:WOS:001114424700001)】；

基金：This work was supported by the National Natural Science Foundation of China (Nos. 22078100, 52102098 and 22008073) and China Post- doctoral Science Foundation (2022M711140) .

语种：英文

外文关键词：Nanoporous phenolic matrix; Thermal conductivity; Molecular dynamics; Lattice Boltzmann method

摘要：Nanoporous phenolic-based composites are widely used as lightweight ablative thermal protection materials, but an accurate prediction of the effective thermal conductivity (aeff) associated with the nanoporous phenolic matrix (NPM) remains a significant challenge. Herein, a series of NPMs with different porosities are prepared, and their thermal conductivities measured experimentally. Precise nanostructure models for NPM are established by measuring the porous structural characteristics. These models have facilitated an accurate predication of aeff by combining the non-equilibrium molecular dynamics with the Lattice Boltzmann method, with an associated maximum deviation less than 5 %. Furthermore, the effects on aeff of intrinsic structure such as porosity, particle overlapping, pore and particle size, in addition to environmental factors are investigated. The results demonstrate that changes in aeff due to porosity are primarily confined to porosity values lower than 50 %. When the degree of particle overlapping is below 0.6, any increase in particle overlapping results in a marked increase in aeff. In addition, aeff exhibits a linear relationship with respect to temperature (below 673 K), and a response to changes in pressure is primarily observed within the range 104-107 Pa. This research provides significant insight into the thermal insulation characteristics and mechanisms of NPM, and can serve as a useful guide for the structural optimization of lightweight thermal protection materials.