Effective thermal conductivity model of aerogel thermal insulation composite

The thermal conductivity model of thermal insulation composites filled with aerogel particles was proposed in this paper. In accordance with the dispersion degree of aerogel particles, the microstructure of thermal insulation composite is divided into three stages, namely, clusters, network chains, and pores. The thermal conductivity of the polymer is related to the dispersion degree of aerogel particles in the composites. Moreover, gaps and holes may be produced in the composite with high-volume fraction. Then, the corresponding models are established and the thermal conductivity equations based on the analysis of the heat transfer in the composite are derived in this paper. In addition, the accuracy of thermal conductivity model raised in this paper is verified by the experiment through preparing a matrix phase filled with aerogel particles. The result is compared with the experimental data. The error at less than 5% between the calculated value and the experimental data implies that the selected value is applicable to the model with clusters.