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Updated: Feb 24, 2026
11:03
An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
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Dynamical density functional theory with hydrodynamic interactions in confined geometries.
B D Goddard1, A Nold2, S Kalliadasis2
1School of Mathematics and Maxwell Institute for Mathematical Sciences, University of Edinburgh, Edinburgh EH9 3FD, United Kingdom.
The Journal of Chemical Physics
|August 12, 2017
Summary
We developed a dynamical density functional theory (DDFT) to study colloidal fluid dynamics, including hydrodynamic interactions (HI). Our method accurately models confined systems, revealing the significant impact of HI.
Area of Science:
- Colloidal science
- Soft matter physics
- Fluid dynamics
Background:
- Colloidal fluids exhibit complex dynamics influenced by inter-particle forces and fluid environment.
- Hydrodynamic interactions (HI), mediated by the surrounding fluid, play a crucial role in confined systems.
- Existing theories may not fully capture the interplay of confinement and HI in colloidal dynamics.
Purpose of the Study:
- To derive a robust dynamical density functional theory (DDFT) incorporating hydrodynamic interactions (HI).
- To validate the DDFT against established methods for colloidal systems.
- To investigate the specific influence of HI on colloidal fluid behavior in confined geometries.
Main Methods:
- Derivation of a DDFT framework from minimal assumptions, including HI.
- Development of an efficient numerical scheme using pseudospectral methods for integro-differential equations.
- Comparison of DDFT predictions with full Langevin equation simulations for hard disk systems.
Main Results:
- The derived DDFT shows excellent agreement with Langevin dynamics simulations.
- The study quantifies the significant effects of HI in partially confined colloidal systems.
- The DDFT provides a computationally efficient tool for studying complex colloidal dynamics.
Conclusions:
- The developed DDFT offers a powerful and accurate approach to model colloidal fluid dynamics with HI.
- Hydrodynamic interactions are critical for understanding colloidal behavior in confined environments.
- This work provides a foundation for further theoretical and computational studies in soft matter physics.
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