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Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
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Turbulence generation through an iterative cascade of the elliptical instability
Ryan McKeown1, Rodolfo Ostilla-Mónico2, Alain Pumir3
1School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA.
Science Advances
|March 12, 2020
Summary
The elliptical instability, driven by vortex interactions, generates turbulence by creating smaller filaments. This process, observed in experiments and simulations, offers a new mechanistic framework for understanding the turbulent cascade.
Area of Science:
- Fluid dynamics
- Turbulence research
- Vortex dynamics
Background:
- Turbulent flow involves energy transfer across scales via eddies.
- A mechanistic framework explaining vortex interactions in the turbulent cascade is lacking.
Purpose of the Study:
- To investigate the role of elliptical instability in the emergence of turbulence.
- To elucidate the mechanism by which vortex interactions drive the turbulent cascade.
Main Methods:
- Theoretical analysis of elliptical instability.
- Numerical simulations of fluid flow.
- Experimental validation of theoretical predictions.
Main Results:
- Elliptical instability iterations drive the cascade of turbulence.
- Nonlinear development generates ordered secondary and tertiary filaments.
- Observed two (experiments) and three (simulations) cascade iterations.
Conclusions:
- Elliptical instability is a fundamental mechanism in turbulent cascade development.
- This finding provides a new mechanistic framework for turbulence research.
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