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Updated: Apr 27, 2026
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Three-dimensional Particle Tracking Velocimetry for Turbulence Applications: Case of a Jet Flow
Published on: February 27, 2016
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The deterministic chaos and random noise in turbulent jet
Tian-Liang Yao1, Hai-Feng Liu1, Jian-Liang Xu1
1Key Laboratory of Coal Gasification and Energy Chemical Engineering of Ministry of Education, East China University of Science and Technology, P.O. Box 272, Shanghai 200237, China.
Chaos (Woodbury, N.Y.)
|July 3, 2014
Summary
This study analyzes turbulent flow using chaotic time series analysis. Findings reveal a direct relationship between Lyapunov exponents and turbulence time scales, suggesting chaotic motion in coherent structures.
Area of Science:
- Fluid Dynamics
- Chaos Theory
- Turbulence Research
Background:
- Turbulent flow is often modeled as a combination of coherent structures and incoherent turbulence.
- Previous work established a method for chaotic time series analysis.
Purpose of the Study:
- To estimate the largest Lyapunov exponent and random noise in round and plane jets.
- To investigate the relationship between turbulence characteristics and chaotic dynamics.
Main Methods:
- Utilized a previously proposed chaotic time series analysis method.
- Applied the method to analyze the near-field dynamics of round and plane jets.
Main Results:
- Largest Lyapunov exponents are inversely proportional to the integral time scale of turbulence for both jet types.
- Random noise exhibits a linear relationship with the Kolmogorov velocity scale in both round and plane jets.
- Proportionality coefficients for Lyapunov exponents and time scales were found to be equal.
Conclusions:
- Random noise likely originates from incoherent turbulence disturbances.
- Coherent structures within turbulence may adhere to the principles of chaotic motion.
- The findings support a unified understanding of turbulent flow dynamics.
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