SilicaGelSim: Prediction of thermal and mechanical properties of Silica Aerogel using atomic scale simulationsAxes: Simulation & Modeling, Materials & Structure DesignLeaders: Takashi Tokumasu (IFS, TU) & Patrice Chantrenne (MATEIS, INSA-Lyon)Participants: Geneviève Foray (MATEIS/MATeB, INSA-Lyon)Development of new material for insulation is of great importance for building renewing and insulation application that require a high ratio between performance and volume. As an example, in France, a significant part of the buildings should be renovated in order to decrease their energy consumption without decrease the usable space in the houses.Silica aerogel are good candidate for such applications. Their highly porous (more than 90% porosity) nanostructure is responsible for the low thermal conductivity (lower than air thermal conductivity), however, this is at the expense of the mechanical properties.Understanding the link between the nanostructure and the thermal and mechanical properties is fundamental since it would allow optimizing the material processing. Previous studies where devoted to the prediction of thermal and mechanical properties of pure silica aerogel using atomic scale simulations. However, during the elaboration, the material surface is functionalized. As the surface to volume ratio is huge, these simulations might not be realistic although they gave interesting results.This aim of this project is to study the influence of the chemical treatment that is used during the material processing (hydrophobic treatment) on the thermal and mechanical properties. It is then important to adapt the simulation methodology (inter atomic potential, coarse grain technique). The collaboration between IFS and MATEIS is necessary in order to gather the abilities in ab initio simulation and molecular dynamics simulation to get realistic simulations.