Development of a Numerical Model to Calculate Heat Transfer in a Cement-Based Material Incorporated with Expanded Perlite Filled with Aerogel.

To solve the problem of high cost and low strength of aerogel-based building materials, expanded perlite filled with aerogel (EPA) has been made by filling the pores in the expanded perlite with aerogel. Adding EPA to cement-based material can reduce the thermal conductivity of the cement-based material. In this study, in order to investigate the thermal conductivity of materials with different content of graded expanded perlite filled with aerogel (GEPA) and non-graded expanded perlite filled with aerogel (NEPA), the experimental and numerical studies have been carried out. The cement-based materials incorporating the EPA (CEPA) have been prepared by replacing different volumes of sand with the NEPA or GEPA, and the thermal conductivity of the CEPA has been measured using the modified transient plane source technique. Based on the law of conservation of energy and the principle of heat transfer, the thermal conductivity models of the CEPA have been developed using the Jacobi iterative method. The results show that the decreasing degree of thermal conductivity of the CEPA is positively correlated with the content of the EPA, and the performance of the GEPA is better than that of the NEPA. As the numerical and experimental results are consistent with each other, the numerical model has been proved to be reasonable and feasible for being widely used to calculate the thermal conductivity of EPA cement-based material, which can be used in sustainable buildings. [ABSTRACT FROM AUTHOR]