A multiscale MD-FE model of diffusion in composite media with internal surface interaction based on numerical...

Area of Science:

• Materials Science
• Chemical Engineering
• Computational Modeling

Background:

• Mass transport in composite materials is influenced by microstructural geometry and chemical interactions.
• Existing methods lack the ability to connect microstructural properties with macroscale diffusion characteristics.

Purpose of the Study:

• To develop a hierarchical multiscale model for diffusion in composite materials.
• To couple microstructural geometry and particle-matrix interactions for continuum diffusion modeling.

Main Methods:

• A novel hierarchical multiscale model bridging molecular dynamics (MD) and finite element (FE) methods.
• Numerical homogenization procedure to evaluate constitutive material parameters for continuum models.
• Implementation for glucose diffusion in silica nanosphere and fibrous structures, and rhodamine 6G in agarose gel.

Main Results:

• The model successfully predicts diffusion coefficients and surface interaction effects.
• Validated against experimental results for glucose and rhodamine 6G diffusion.
• Demonstrated applicability to diverse microstructures like nanospheres and fibrous networks.

Conclusions:

• The developed microstructural, homogenization, and continuum models provide a new platform for predicting mass diffusion.
• This approach is valuable for complex biological environments and composite materials in applications such as drug delivery and nanoporous catalysts.