Acoustical properties of granular aerogel agglomerates

Abstract

Granular aerogel agglomerates obtain their unique mechanical and functional properties from their underlying mesoporous structure and intergranular interactions. In this presentation, we focus on the acoustical properties of granular aerogel layers and present experimental results characterizing the absorption behavior of granular silica aerogels with average particle sizes ranging from 5 μm to 2 mm. Our results show that the absorption behavior of granular aerogels strongly depends on the average particle size. To better understand this particle size dependence, we model the granular agglomerates using Biot’s limp and poro-elastic formulation. Finally, we use the developed model to design layered aerogel granular stacks with wideband sound absorption properties.