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Published on: May 20, 2014
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Driven colloidal fluids: construction of dynamical density functional theories from exactly solvable limits.
Alberto Scacchi1, Matthias Krüger, Joseph M Brader
1Department of Physics, University of Fribourg, CH-1700 Fribourg, Switzerland.
Summary
Dynamical density functional theory (DDFT) struggles with driven systems. This study corrects DDFT by accounting for flow-induced distortions, accurately predicting shear-induced migration in colloidal dispersions.
Area of Science:
- Soft Matter Physics
- Statistical Mechanics
- Computational Physics
Background:
- Classical dynamical density functional theory (DDFT) approximates nonequilibrium systems under Brownian dynamics.
- DDFT fails for driven systems like sheared colloidal dispersions due to inadequate handling of flow-induced pair correlation distortions.
Purpose of the Study:
- To systematically correct DDFT for driven systems.
- To improve the theoretical treatment of flow-induced effects in colloidal systems.
Main Methods:
- Developing a corrected DDFT by incorporating second-order flow-rate corrections to pair correlations.
- Applying the corrected theory to analyze Poiseuille flow in colloidal dispersions.
Main Results:
- The corrected DDFT accurately predicts particle accumulation in low shear rate regions (shear-induced migration).
- Theoretical predictions show good agreement with Brownian dynamics simulations.
Conclusions:
- The developed DDFT correction method enhances the applicability of DDFT to driven colloidal systems.
- The findings provide a more robust theoretical framework for understanding shear-induced phenomena in complex fluids.
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