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Updated: Jul 7, 2026
11:03
An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Thermodynamically guided nonequilibrium Monte Carlo method for generating realistic shear flows in polymeric systems
1Department of Chemical Engineering, University of Patras and FORTH-ICE/HT, Patras, GR 26504, Greece.
Physical Review Letters
|February 1, 2008
Summary
This study introduces a new atomistic Monte Carlo method to simulate materials under flow. The novel approach accurately models non-equilibrium systems, matching results from nonequilibrium molecular dynamics simulations.
Area of Science:
- Computational chemistry
- Materials science
- Statistical mechanics
Background:
- Simulating materials under flow requires methods that go beyond equilibrium conditions.
- Traditional methods struggle to accurately capture the structural dynamics of systems subjected to external forces like shear.
Purpose of the Study:
- To develop a thermodynamically guided atomistic Monte Carlo methodology for simulating non-equilibrium systems.
- To incorporate a tensorial variable into the statistical ensemble to represent system structure under flow.
Main Methods:
- Expanded the statistical ensemble in Monte Carlo simulations to include a tensorial variable for system structure.
- Iteratively determined the conjugate field for a given shear rate using independent nonequilibrium molecular dynamics simulations.
Main Results:
- Successfully simulated the effect of flow on the conformation of a C50H102 polyethylene liquid.
- Demonstrated that the expanded Monte Carlo method yields results identical to nonequilibrium molecular dynamics.
Conclusions:
- The developed thermodynamically guided Monte Carlo method is a viable approach for simulating non-equilibrium systems under flow.
- This method provides an accurate alternative to nonequilibrium molecular dynamics for studying fluid behavior.
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