Hybrid atomistic simulation of fluid uptake in a deformable solid

Area of Science:

• Materials Science
• Physics
• Computational Chemistry

Background:

• Fluid diffusion into solids can induce stresses, affecting further fluid absorption.
• Understanding this interplay is crucial for predicting material behavior under fluid exposure.

Purpose of the Study:

• To investigate the coupled effects of diffusional and elastic fields during fluid imbibition in deformable solids.
• To model and analyze fluid permeation dynamics and their impact on solid structure.

Main Methods:

• Utilized a hybrid Monte Carlo-molecular dynamics simulation scheme.
• Coupled a fluid reservoir to a deformable solid model.
• Monitored structural and dimensional changes during fluid uptake.

Main Results:

• Quantified compositional strain resulting from fluid imbibition.
• Determined the diffusion coefficient within the Fickian regime.
• Observed and identified potential mechanisms for a non-Fickian diffusion regime with large, mobile fluid atoms.

Conclusions:

• The study successfully modeled the complex interplay between fluid diffusion and solid deformation.
• Highlights the existence of distinct Fickian and non-Fickian diffusion behaviors.
• Provides insights into the mechanisms governing fluid-solid interactions.