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Updated: Jul 17, 2026
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Methods for Measuring the Orientation and Rotation Rate of 3D-printed Particles in Turbulence
Published on: June 24, 2016
Dynamic correlations in stochastic rotation dynamics.
1School of Physics and Astronomy, University of Minnesota, 116 Church Street SE, Minneapolis, MN 55455, USA.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|February 7, 2007
Summary
This study measures dynamic correlation functions in stochastic rotation dynamics (SRD) to determine transport coefficients. It confirms zero bulk viscosity for SRD and analyzes corrections to self-diffusion and shear viscosity.
Area of Science:
- Computational physics
- Fluid dynamics
- Statistical mechanics
Background:
- Stochastic Rotation Dynamics (SRD) is a particle-based algorithm for simulating fluctuating hydrodynamics.
- Accurate determination of transport coefficients is crucial for understanding fluid behavior.
Purpose of the Study:
- To measure dynamic correlation functions for SRD, specifically the dynamic structure factor, vorticity, and entropy density.
- To obtain unbiased longitudinal transport coefficients, including thermal diffusivity and bulk viscosity.
- To analyze corrections to self-diffusion and shear viscosity at small mean free paths.
Main Methods:
- Measurement of dynamic structure factor, vorticity, and entropy density dynamic correlation functions.
- Analysis of corrections to transport coefficients arising from the breakdown of molecular chaos approximation.
- Analytical derivation of collision partner probabilities for small mean free paths.
Main Results:
- Unbiased values for thermal diffusivity and bulk viscosity were obtained.
- For the first time, it is demonstrated that the bulk viscosity for the SRD algorithm is zero.
- Leading order correlation corrections to self-diffusion and shear viscosity were derived.
- Analytical expressions for transport coefficients accurately describe the SRD fluid.
Conclusions:
- The study provides a comprehensive understanding of the SRD algorithm at the kinetic level.
- SRD is validated as an accurate method for simulating fluctuating hydrodynamics.
- Analytic expressions for transport coefficients are confirmed to be highly accurate for SRD simulations.
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