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Updated: Jul 5, 2026
06:42
Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
On the linear stability of Stokes layers.
P J Blennerhassett1, Andrew P Bassom
1School of Mathematics and Statistics, University of New South Wales, Sydney, NSW 2052, Australia. p.blennerhassett@unsw.edu.au
Summary
This study theoretically confirms the instability of oscillatory fluid flows, like the Stokes layer, at high Reynolds numbers. Discrepancies with experimental data highlight areas for future research in fluid dynamics.
Area of Science:
- Fluid dynamics
- Hydrodynamics
- Nonlinear dynamics
Background:
- Oscillatory flows are prevalent in nature and engineering.
- Understanding the transition to turbulence in time-periodic flows is crucial.
- The linear stability of the classical flat Stokes layer has been a long-standing problem.
Purpose of the Study:
- To theoretically investigate the stability of time-periodic fluid motions.
- To extend stability analysis to various geometries including channels, pipes, and oscillating cylinders.
- To reconcile theoretical predictions with experimental observations of flow instability.
Main Methods:
- Linear stability analysis of the flat Stokes layer.
- Numerical calculations for planar and confined oscillatory flows.
- Comparison of theoretical predictions with experimental data.
Main Results:
- Rigorous theoretical confirmation of the instability of the planar Stokes layer at high Reynolds numbers.
- Extension of analysis to channel, pipe, and torsionally oscillating cylinder flows.
- Identification of significant discrepancies between theoretical predictions and experimental results for instability onset in these geometries.
Conclusions:
- Theoretical models confirm the instability of certain oscillatory flows.
- Current theoretical frameworks may not fully capture the complex dynamics leading to turbulence in these systems.
- Further experimental and theoretical work is needed to resolve discrepancies and advance understanding of flow stability.
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