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Updated: Sep 26, 2025
06:42
Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
9.7K
Destabilizing resonances of precessing inertia-gravity waves
N Benkacem1, A Salhi2,3, A Khlifi1
1Université de Tunis El Manar, Faculté des Sciences de Tunis, Laboratoire Matériaux Organisation et Propriétés, 2092 Tunis, Tunisie.
Physical Review. E
|April 16, 2022
Summary
This study investigates instabilities in stratified precessing fluids, extending previous work. It reveals that stable stratification suppresses subharmonic instability, with viscosity
Area of Science:
- Fluid dynamics
- Geophysics
- Astrophysics
Background:
- Investigates instabilities in stratified precessing fluids, building upon Mahalov's work.
- Considers stably stratified Boussinesq framework with an external Coriolis force.
Purpose of the Study:
- Analyze the stability of superimposed perturbations in a modified base flow.
- Characterize resonant instability cases and the effect of stratification and viscosity.
Main Methods:
- Exact solution of Boussinesq-Euler equations for modified velocity and buoyancy.
- Stability analysis using Fourier (Kelvin) modes in a Cartesian system.
- Asymptotic analysis for leading order in Poincaré number (ɛ) and numerical computations for higher-order resonances.
Main Results:
- Identified subharmonic instability (n=1) for 0≤N<Ω/2, with maximal growth rate dependent on stratification.
- Stable stratification (N≥0.5Ω) suppresses subharmonic instability.
- Numerical analysis of resonant cases n=2,3,4,5 and brief investigation of viscosity and unstable stratification (N²<0).
Conclusions:
- Subharmonic instability is a key feature in this fluid system, significantly influenced by stratification.
- The study provides insights into the complex dynamics of rotating stratified fluids.
- Viscosity and unstable stratification introduce further complexities to fluid instabilities.
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