纳米多孔结构气凝胶传热模型及绝热机理研究

Research on Heat Transfer Model and Thermal Insulation Mechanism of Nanoporous Aerogels

气凝胶是一种具有纳米多孔结构的超级绝热材料,可广泛应用于航空航天、热能传输、节能建筑等领域。在结构单元的气固耦合传热基础上,建立了纳米多孔结构气凝胶的传热模型,推导了有效热导率表达式,并将该传热模型的计算结果与实验结果进行对比研究,进一步验证了该模型的准确合理性。计算分析了不同含量、不同纤维增强的SiO2复合气凝胶的绝热系数,为进一步优化设计多孔结构材料垫定了良好的理论基础。

Aerogel is a super thermal insulation materials with nanoporous structure.It can be widely used in aerospace,thermal energy transmission,energy-saving construction and other fields.Based on the gas-solid coupling heat transfer of structural units,the heat transfer model of aerogels is established,and the expression of effective thermal conductivity is deduced.Finally,the calculation results of the heat transfer model are compared with the experimental results to verify the accuracy of the model.On this basis,the adiabatic constant of different content and fiber reinforced aerogels composite is calculated and analyzed,which lays a good theoretical foundation for further optimizing the design of porous structure materials.