Thermal conductivity of glass fiber-reinforced silica aerogels using molecular dynamics simulations

Abstract

Silica aerogels are low-density, low-thermal conductivity, and highly porous solids used in a wide range of applications. In the present work, the glass fibers-reinforced silica aerogels nanocomposite models were investigated for thermal conductivity using molecular dynamics (MD) simulations. Here, the glass fibers weight percentage (% wt) was varied from 2.14 to 21.20%, i. e., the density of the silica aerogel nanocomposite ranged from 252 to 307 kg m−3. The thermal conductivity increases with the % wt of glass fibers for the considered range. However, the increase was insignificant, i. e., from 0.0357 to 0.048 W m−1 K−1. Moreover, the thermal conductivity varies with the density of nanocomposite according to a power-law with an exponent of 1.90 ± 0.18. Furthermore, the obtained thermal conductivity values of silica aerogels and their nanocomposites are in good agreement with experimental and computational studies. The outcome shows that the glass fibers-reinforced silica aerogels nanocomposites can be used for low-thermal conductivity applications.