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The Raspberry model for hydrodynamic interactions revisited. II. The effect of confinement
Joost de Graaf1, Toni Peter1, Lukas P Fischer1
1Institute for Computational Physics (ICP), University of Stuttgart, Allmandring 3, 70569 Stuttgart, Germany.
The Journal of Chemical Physics
|September 3, 2015
Summary
The raspberry model accurately simulates colloidal particle dynamics. Adding internal coupling points corrects discrepancies in confined geometries, improving hydrodynamic interaction simulations.
Area of Science:
- Computational physics and chemistry
- Fluid dynamics
- Colloidal science
Background:
- The raspberry model combines lattice-Boltzmann (LB) and Langevin molecular dynamics for simulating colloidal suspensions.
- Previous work evaluated its effectiveness for simple-cubic crystals in the Stokes regime.
Purpose of the Study:
- To assess the raspberry model's accuracy in reproducing hydrodynamic interactions for particles confined between parallel plates.
- To investigate discrepancies in translational and rotational mobilities and propose corrections.
Main Methods:
- Utilized LB simulations to model particle dynamics in confining geometries.
- Compared simulation results with theoretical expressions and finite-element calculations.
- Investigated the impact of surface and internal coupling points on model accuracy.
Main Results:
- A discrepancy in translational and rotational mobilities was observed with only surface coupling points.
- Adding internal coupling points successfully corrected these discrepancies in confined geometries.
- The raspberry model accurately captures hydrodynamic interactions with planar walls up to one LB lattice spacing.
Conclusions:
- The raspberry model, particularly with internal coupling points, is effective for simulating hydrodynamics in confined colloidal systems.
- The study validates and refines the application of the raspberry model for complex geometries.
- Accurate simulation of colloidal suspensions in confined environments is crucial for understanding various physical phenomena.
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