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Updated: Jul 12, 2025
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The Diffusion of Passive Tracers in Laminar Shear Flow
Published on: May 1, 2018
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Observation of Traveling Breathers and Their Scattering in a Two-Fluid System
Yifeng Mao1, Sathyanarayanan Chandramouli2, Wenqian Xu1
1Department of Applied Mathematics, University of Colorado, Boulder, Colorado 80309, USA.
Physical Review Letters
|October 20, 2023
Summary
Traveling breathers (TBs) with oscillatory tails, predicted 50 years ago, have been observed. These nonlinear waves generalize the breather concept and exhibit elastic scattering in various systems.
Area of Science:
- Nonlinear dynamics
- Fluid mechanics
- Wave phenomena
Background:
- Theoretical prediction of traveling breathers (TBs) dates back nearly 50 years.
- Breathers are a fundamental concept in nonlinear wave physics.
- Understanding nonlinear wave behavior is crucial in various scientific domains.
Purpose of the Study:
- To experimentally observe and characterize traveling breathers (TBs).
- To generalize the concept of breathers to strongly nonlinear systems.
- To investigate the interaction and scattering properties of TBs.
Main Methods:
- Generation of TBs in a core-annular flow.
- Interaction of a soliton with a nonlinear periodic (cnoidal) carrier wave.
- Observation and analysis of bright and dark TBs.
Main Results:
- Experimental realization of traveling breathers (TBs) with large-amplitude oscillatory tails.
- Creation of two strongly nonlinear TB families.
- Observed TBs move faster (bright) or slower (dark) than the carrier, imparting a phase shift.
- Agreement with theoretical model equations was achieved.
- Scattering of TBs was found to be physically elastic.
Conclusions:
- The observation of TBs confirms a long-standing theoretical prediction.
- TBs represent a generalization of the breather concept applicable to diverse systems.
- The findings have implications for both continuum and discrete nonlinear systems.
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