Determination of the Effective Thermal Conductivity of Aerogel-Based Coating Mortars Using Numerical Simulations—Random Packing

Abstract

Aerogel-based coating mortars have declared thermal conductivities of 0.03–0.05 W/(m · K), similar to those of conventional thermal insulation materials. Due to the high porosity and fragility of aerogel granules, the material obtains a reduced mechanical strength compared to conventional mortars. Recently, there has been a large research effort on developing new mixtures with improved thermal and mechanical properties. This paper presents and evaluates two-dimensional numerical simulations, based on the random packing technique, as an alternative method to laboratory measurements in predicting the effective thermal conductivity of these mortars. Experimental data from the literature, on thermal conductivity of aerogel-based coating mortars containing 50–90 vol% aerogels were used to validate the simulation results. In this preliminary validation study, a relative error of 6–10% was observed. Future work can focus on improving the accuracy and including the prediction of mechanical properties in the suggested model.