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Updated: May 10, 2026
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Measurements of Local Instantaneous Convective Heat Transfer in a Pipe - Single and Two-phase Flow
Published on: April 30, 2018
Streamwise-localized solutions at the onset of turbulence in pipe flow
M Avila1, F Mellibovsky, N Roland
1Institute of Fluid Mechanics, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany. marc.avila@fau.de
Physical Review Letters
|June 18, 2013
Summary
Researchers discovered periodic solutions that organize turbulent fluid flow, similar to chaotic systems. These localized solutions explain the building blocks of complex turbulent dynamics and transients.
Area of Science:
- Fluid dynamics
- Chaos theory
- Turbulence research
Background:
- Governing equations for fluid flow are known, but analytical solutions for turbulent motion remain elusive.
- A recent hypothesis suggests turbulence is organized by unstable solutions, analogous to low-dimensional chaotic systems.
Purpose of the Study:
- To investigate the proposed organization of turbulence around unstable solutions.
- To identify and characterize periodic solutions within the governing equations of fluid flow.
Main Methods:
- Numerical or analytical investigation of fluid flow equations.
- Identification of periodic solutions exhibiting specific characteristics.
Main Results:
- Discovery of spatially localized periodic solutions.
- Demonstration that these solutions resemble intermittent turbulence.
- Evidence that turbulent transients originate from these periodic solution branches.
Conclusions:
- Periodic solutions are key building blocks for understanding complex turbulent dynamics.
- The discovered solutions provide a new framework for analyzing turbulence.
- This finding supports the analogy between turbulence and low-dimensional chaotic systems.
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