Abstract
Silica aerogels are highly porous 3D nanostructures and have exhibited excellent physio-chemical properties. Although silica aerogels have broad potential in many fields, the poor mechanical properties greatly limit further applications. In this study, we have applied the finite volume method (FVM) method to calculate the mechanical properties of silica aerogels with different geometric properties such as particle size, pore size, ligament diameter, etc. The FVM simulation results show that a power law correlation existing between relative density and mechanical properties (elastic modulus and yield stress) of silica aerogels, which are consistent with experimental and literature studies. In addition, depending on the relative densities, different strategies are proposed in order to synthesize silica aerogels with better mechanical performance by adjusting the distribution of pore size and ligament diameter of aerogels. Finally, the results suggest that it is possible to synthesize silica aerogels with ultra-low density as well as high strength and stiffness as long as the textural features are well controlled. It is believed that the FVM simulation methodology could be a valuable tool to study mechanical performance of silica aerogel based materials in the future.
Highlights
Silica aerogels have attracted considerable attention due to the high porosity, low thermal conductivity, high surface area, and good chemical stability, etc. [1,2,3,4]
Different geometric parameters of the silica aerogels are indicated with red rectangular in Figure 2a, such as pore size labeled with φ, ligament diameter labeled with s and particle size labeled with d
The finite volume method (FVM) is used to simulate and calculate the mechanical properties of silica aerogels, which are fabricated with different particle sizes, pore sizes and ligament diameters by the sol-gel method
Summary
Silica aerogels have attracted considerable attention due to the high porosity, low thermal conductivity, high surface area, and good chemical stability, etc. [1,2,3,4]. Because of these unique physio-chemical properties, silica aerogels have promising applications in many areas such as building insulation, structural materials, automotive and aerospace [5,6,7] Despite this great potential, poor mechanical performance still limits its large-scale and commercial applications. Brunauer–Emmett-Teller (BET) analysis, the geometrical properties of silica aerogel such as pore size, ligament diameter, and particle size can be obtained According to these geometric parameters, an approximate structure of silica aerogel with the density of 0.098 (ρ = 0.098) is modeled, whose mechanical properties are subsequently simulated by the finite volume method (FVM). The FVM method is used to simulate and calculate other mechanical properties of these two different models, in which the compression behavior, elastic modulus, and yield stress can be accessed. The computational data are compared with experimental results to verify the feasibility of the FVM simulation method developed in this work
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
