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Visually Based Characterization of the Incipient Particle Motion in Regular Substrates: From Laminar to Turbulent Conditions
Published on: February 22, 2018
Boltzmann kinetic equation for filtered fluid turbulence
1Aerospace Engineering Department, Texas A&M University, College Station, Texas 77843, USA.
Physical Review Letters
|August 7, 2007
Summary
We developed a kinetic Boltzmann equation to describe fluid turbulence, unifying kinetic and continuum models. This advances numerical methods for diverse flow physics.
Area of Science:
- Fluid dynamics
- Statistical mechanics
- Computational physics
Background:
- Turbulence modeling faces challenges in reconciling kinetic and continuum descriptions.
- Existing models struggle to capture both continuum and noncontinuum effects accurately.
- Closure modeling issues persist in kinetic Boltzmann and Navier-Stokes equations.
Purpose of the Study:
- To develop a unified kinetic Boltzmann equation for filtered fluid turbulence.
- To elucidate the impact of unresolved turbulent motion on the resolved distribution function.
- To reconcile closure modeling discrepancies between kinetic and continuum approaches.
Main Methods:
- Formulation of a kinetic Boltzmann equation applicable to filtered fluid turbulence.
- Analysis of the effect of sub-grid scale turbulence on the resolved distribution function.
- Reconciliation of closure models for kinetic and continuum descriptions.
Main Results:
- A novel kinetic Boltzmann equation for filtered fluid turbulence is established.
- The influence of unresolved turbulent motions on the resolved distribution function is clarified.
- Closure modeling issues are addressed, bridging kinetic and continuum theories.
Conclusions:
- The developed kinetic Boltzmann equation offers a unified approach to turbulence modeling.
- This work facilitates the development of numerical methods valid across a wide range of flow regimes.
- The findings pave the way for integrating kinetic and continuum turbulence modeling.
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