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Stress tensors of multiparticle collision dynamics fluids
Roland G Winkler1, Chien-Cheng Huang
1Institut für Festkörperforschung, Forschungszentrum Jülich, D-52425 Jülich, Germany. r.winkler@fz-juelich.de
The Journal of Chemical Physics
|February 26, 2009
Summary
This study derives stress tensors for multiparticle collision dynamics, a fluid simulation method. Analytical expressions for shear viscosity show good agreement with simulations.
Area of Science:
- Computational physics
- Fluid dynamics
- Mesoscale simulation
Background:
- Multiparticle collision dynamics (MPCD) is a particle-based mesoscale simulation method for fluctuating fluids.
- Existing methods lack detailed stress tensor derivations applicable to various boundary conditions.
Purpose of the Study:
- To derive stress tensors for MPCD, enabling accurate fluid property calculations.
- To provide analytical expressions for shear viscosity based on these stress tensors.
Main Methods:
- Derivation of internal and external stress tensors for MPCD systems.
- Consideration of systems with periodic boundary conditions and confined fluids.
- Determination of stress tensors for systems with embedded particles.
Main Results:
- Two equivalent expressions for stress tensors were derived: internal and external.
- Analytical expressions for shear viscosity were obtained from the derived stress tensors.
- Simulations confirmed good agreement between numerical results and analytical viscosity expressions.
Conclusions:
- The derived stress tensors accurately represent fluid behavior in MPCD simulations.
- The study provides a robust method for calculating shear viscosity in mesoscale fluid simulations.
- MPCD is validated as a reliable method for simulating complex fluid systems.
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