Gas Transport in Porous Media: Simulations and Experiments on Partially Densified Aerogels

TL;DR

This paper presents a computer model that accurately simulates gas permeability and pore surface characteristics in partially densified silica aerogels, integrating experimental data with structural and transport modeling.

Contribution

The study introduces a novel computer simulation that links aerogel structure with gas transport properties, validated against experimental permeability and adsorption data.

Findings

Model accurately predicts gas permeability dependence on density.

Model accounts for pore surface area variations with density.

Simulation aligns with experimental nitrogen adsorption measurements.

Abstract

The experimental density dependence of gas (argon and nitrogen) permeability of partially densified silica aerogels in the Knudsen regime is quantitatively accounted for by a computer model. The model simulates both the structure of the sintered material and the random ballistic motion of a point particle inside its voids. The same model is also able to account for the densit y dependence of the specific pore surface as measured from nitrogen adsorption experiments.