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04:35
Preparation of Free-Surface Hyperbolic Water Vortices
Published on: July 28, 2023
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Vortex gas modeling of turbulent circulation statistics
G B Apolinário1, L Moriconi1, R M Pereira2
1Instituto de Física, Universidade Federal do Rio de Janeiro, Caixa Postal 68528, CEP: 21945-970, Rio de Janeiro, RJ, Brazil.
Physical Review. E
|November 20, 2020
Summary
This study models turbulent flows as vortex gases to analyze circulation statistics. The findings align with empirical data, explaining key features of turbulent cascades.
Area of Science:
- Fluid Dynamics
- Turbulence Theory
- Statistical Mechanics
Background:
- Turbulent cascades exhibit complex multiscale structures.
- Understanding circulation statistics is key to characterizing turbulence.
- Reynolds numbers and length scales influence circulation moments and probability distributions.
Purpose of the Study:
- Investigate circulation statistics in 3D turbulent flows.
- Address theoretical challenges regarding Reynolds number and scale dependence.
- Explain heavy-tailed probability distribution functions of circulation.
Main Methods:
- Developed a model combining structural turbulence theory (vortex gases) with Obukhov-Kolmogorov intermittency framework.
- Analyzed statistical properties of circulation for planar cuts of 3D flows.
- Compared model results with empirical data from direct numerical simulations.
Main Results:
- Successfully reproduced key statistical features of circulation.
- Demonstrated agreement between model predictions and empirical observations.
- Provided insights into the dependence of circulation moments and distribution shapes on flow parameters.
Conclusions:
- The vortex gas model effectively captures essential circulation statistics in turbulent flows.
- The study reconciles theoretical challenges in turbulence research.
- Findings support the phenomenological framework for small-scale intermittency in turbulence.
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