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Published on: July 19, 2016
Coherent structure analysis of spatiotemporal chaos
Jung1, Wang, Wackerbauer
1Department of Physics and Astronomy, Ohio University, Athens, Ohio 45701, USA.
Summary
We developed a new method to measure spatiotemporal turbulence in complex systems. This technique reveals power-law scaling in spiral turbulence and quantifies the transition to chaotic behavior using an entropy measure.
Area of Science:
- Complex systems analysis
- Nonlinear dynamics
- Statistical physics
Background:
- Spatiotemporal turbulence is a complex phenomenon observed in various extended systems.
- Quantifying and characterizing turbulence transitions remains a challenge in nonlinear dynamics.
Purpose of the Study:
- To introduce a novel measure for quantifying spatiotemporal turbulence.
- To analyze the statistical properties of coherent structures in turbulent systems.
- To define an entropy measure for detecting turbulence transitions.
Main Methods:
- Coherent structure decomposition of evolving systems.
- Statistical analysis of decomposed structures.
- Application to cellular excitable media and CO oxidation on Pt(100).
Main Results:
- Identified power-law scaling in the size distribution of coherent space-time structures during spiral turbulence.
- Demonstrated the effectiveness of the measure in characterizing turbulence.
- Observed a sharp increase in the defined entropy measure at the transition to turbulence.
Conclusions:
- The developed measure accurately quantifies spatiotemporal turbulence.
- Coherent structure decomposition provides insights into turbulence dynamics.
- The entropy measure serves as a sensitive indicator for turbulence onset.
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