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An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
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Dynamic density functional theory with inertia and background flow
R D Mills-Williams1, B D Goddard2, A J Archer3
1Edinburgh Designs Ltd., 27 Ratcliffe Terrace, Edinburgh EH9 1SX, United Kingdom.
The Journal of Chemical Physics
|May 15, 2024
Summary
We developed a new dynamic density functional theory (DDFT) to model colloidal systems driven by complex fluid flows. Our approach accurately captures non-equilibrium dynamics and matches existing theories in standard limits.
Area of Science:
- Statistical Mechanics
- Soft Matter Physics
- Fluid Dynamics
Background:
- Colloidal systems are crucial in soft matter.
- Understanding non-equilibrium dynamics is key.
- Existing theories often simplify background flow effects.
Purpose of the Study:
- To develop a dynamic density functional theory (DDFT) for colloidal systems under general background flows.
- To incorporate inertia and time-dependent flows into DDFT.
- To model externally driven passive colloidal systems out of equilibrium.
Main Methods:
- Derived nonlinear, nonlocal partial differential equations from nonequilibrium Langevin dynamics.
- Incorporated local liquid bath velocity and inertia.
- Used numerical solutions for hard sphere systems.
Main Results:
- Developed a DDFT framework for inhomogeneous, time-dependent flows.
- Demonstrated agreement with existing DDFTs in the overdamped limit.
- Provided numerical solutions for colloidal flow in various domains.
Conclusions:
- The new DDFT accurately describes colloidal dynamics under complex flows.
- The framework extends DDFT to include inertia and time-dependent effects.
- Numerical simulations validate the model against prior theories.
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