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09:58
Investigating the Three-dimensional Flow Separation Induced by a Model Vocal Fold Polyp
Published on: February 3, 2014
Defect turbulence in inclined layer convection
Karen E Daniels1, Eberhard Bodenschatz
1Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA.
Physical Review Letters
|January 22, 2002
Summary
This study investigates undulation chaos in fluid convection, finding its onset matches theoretical predictions. Experiments reveal a competition between ordered and chaotic states, with a universal defect behavior in turbulence.
Area of Science:
- Fluid dynamics
- Nonlinear dynamics
- Chaos theory
Background:
- Inclined layer convection exhibits complex spatiotemporal dynamics.
- Undulation chaos is a defect turbulent state observed in fluid systems.
- Understanding defect behavior is crucial for characterizing chaotic fluid states.
Purpose of the Study:
- To experimentally investigate the defect turbulent state of undulation chaos.
- To determine the onset conditions for undulation chaos.
- To analyze defect dynamics and derive a universal probability distribution function.
Main Methods:
- Experimental measurements of defect density and undulation wave number.
- Varying the driving force to observe transitions between states.
- Quantifying defect creation, annihilation, entering, and leaving rates.
Main Results:
- The onset of undulation chaos aligns with theoretical predictions for stable, stationary undulations.
- A bistability between ordered undulations (fixed-point attractor) and undulation chaos (spatiotemporal chaos) was observed at stronger driving.
- A universal probability distribution function for defect behavior was derived and experimentally validated.
Conclusions:
- Undulation chaos in inclined layer convection has a predictable onset.
- Fluid systems can exhibit bistability between ordered and chaotic dynamics.
- Defect dynamics in turbulent states follow a universal statistical behavior.
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