Theoretical Modeling of the Thermal and Mechanical Structure-Property Relationships in Aerogels

Abstract

Aerogel-based materials are being currently developed at a pace faster than ever before. This has broadened their spectrum of applications to address the state-of-the-art issues of thermal and electrical energy storage and management. Given the rise in theoretical studies investigating the structure-property relationships in aerogels, a unique opportunity is being presented to reinforce experimentally driven materials development with theoretical models. To that end, the effective thermal conductivity in aerogels, resulting from contributions due to radiation and solid and gaseous conduction, has been theoretically described and the proposed models have been validated with the experimental data, and applied to develop aerogels and aerogel composites for thermal insulation. In this chapter, such models and their effect on developing aerogels for thermal energy storage and management are explored. With increasing applications, the mechanical properties play an important role, as many aerogels exhibit brittle behavior. Accordingly, an overview on the modeling of their mechanical properties is also addressed in this chapter. First, all-atom simulation models are reviewed, followed by coarse-grained ones and finally, micromechanical ones.