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Updated: May 14, 2026
09:58
Investigating the Three-dimensional Flow Separation Induced by a Model Vocal Fold Polyp
Published on: February 3, 2014
Evolution of a barotropic shear layer into elliptical vortices
Anirban Guha1, Mona Rahmani, Gregory A Lawrence
1Department of Civil Engineering, University of British Columbia, Vancouver, Canada V6T 1Z4. aguha@mail.ubc.ca
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|February 16, 2013
Summary
A piecewise linear shear layer generates unique elliptical vortices via Kelvin-Helmholtz instability (KHI). This KHI arises from interacting counterpropagating vorticity waves, explaining vortex formation in planetary atmospheres and oceans.
Area of Science:
- Fluid dynamics
- Geophysical and astrophysical fluid dynamics
Background:
- The Kelvin-Helmholtz instability (KHI) typically forms spiral billows in barotropic shear layers.
- A piecewise linear shear layer exhibits a distinct KHI characterized by elliptical vortices and thin braids.
Purpose of the Study:
- To elucidate the mechanism behind the KHI in piecewise linear shear layers.
- To investigate the dynamics of elliptical vortices and associated braids.
Main Methods:
- Direct numerical simulation
- Contour dynamics
Main Results:
- The interaction of two counterpropagating vorticity waves is identified as the sole cause of this KHI.
- Observed phenomena include oscillations in vorticity wave amplitude, elliptical vortex rotation and nutation, and braid straining.
Conclusions:
- The study explains the formation and evolution of elliptical vortices in various geophysical and astrophysical flows.
- Findings offer insights into phenomena such as meddies, polar vortices, and Jovian/Neptunian vortices.
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