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Liquid dynamics in a crowded environment: Bond percolation vs site percolation
Piotr Polanowski1, Andrzej Sikorski2
1Department of Molecular Physics, Łódź University of Technology, Żeromskiego 116, 90-543 Łódź, Poland.
Chaos (Woodbury, N.Y.)
|July 1, 2025
Summary
Liquid diffusion with obstacles is complex, not reducible to simple percolation. Site percolation models show more mobile liquid molecules than bond percolation, highlighting morphology
Area of Science:
- Computational physics
- Materials science
- Statistical mechanics
Background:
- Understanding liquid diffusion in porous media is crucial for various applications.
- Existing models often simplify diffusion problems into site or bond percolation, which may not capture real-world complexity.
- Real media diffusion is a complex interplay between site and bond percolation phenomena.
Purpose of the Study:
- To compare site and bond percolation models for liquid diffusion in the presence of obstacles.
- To investigate the influence of obstacle morphology on liquid molecule mobility.
- To utilize the dynamic lattice liquid algorithm for correlated motion analysis.
Main Methods:
- Extensive computer simulations on a dense, athermal, 2D liquid model on a triangular lattice.
- Comparison of liquid molecule mobility under site versus bond percolation scenarios.
- Analysis using the dynamic lattice liquid algorithm to model correlated element motion.
Main Results:
- Liquid molecules exhibit significantly higher mobility in the site percolation model compared to the bond percolation model at equivalent obstacle concentrations.
- Increased obstacle concentration or blocking probability further enhances mobility differences between site and bond models.
- System dynamics are strongly correlated with system morphology, not just obstacle quantity.
Conclusions:
- Liquid diffusion in systems with obstacles cannot be simplified to purely site or bond percolation.
- The morphology of obstacles and available channels critically influences system dynamics.
- Site percolation models provide a more accurate representation of enhanced liquid mobility in certain complex media.
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