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Updated: Jun 4, 2025
06:42
Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
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Competition between merging and bifurcation in the generalized Rayleigh-Taylor instability
Q Cauvet1, B Bernecker1, B Canaud1
1<a href="https://ror.org/00kn4eb29">CEA, DAM</a>, DIF- 91297 Arpajon, France and <a href="https://ror.org/03xjwb503">Université Paris-Saclay</a>, CEA, Laboratoire Matière en Conditions Extrêmes (LMCE), 91680 Bruyères-le-Châtel, France.
Physical Review. E
|December 18, 2024
Summary
The generalized Rayleigh-Taylor instability exhibits two nonlinear regimes: inertial growth (h∝t²) and collisional growth (h∝t). The collisional regime, featuring frictional forces, maintains constant structure sizes and highlights the role of bifurcation processes.
Area of Science:
- Fluid dynamics
- Plasma physics
- Astrophysical phenomena
Background:
- The Rayleigh-Taylor instability drives mixing in fluids with different densities under acceleration.
- Understanding nonlinear evolution is crucial for astrophysical jets, inertial confinement fusion, and supernovae.
Purpose of the Study:
- To investigate the nonlinear dynamics of generalized Rayleigh-Taylor instability with a frictional force.
- To analyze the distinct growth regimes and structural evolution influenced by collisional effects.
Main Methods:
- Numerical simulations of fluid interfaces.
- Extension of Alon's statistical model incorporating asymptotic bubble velocity and merging.
- Inclusion of a frictional force simulating interpenetrating fluid collisions.
Main Results:
- Identified two nonlinear regimes: inertial (h∝t²) and collisional (h∝t).
- The collisional regime, characterized by friction, leads to self-similar structures of constant size.
- Demonstrated the significance of bifurcation (bubble breakup) in the collisional regime.
Conclusions:
- Frictional forces fundamentally alter Rayleigh-Taylor instability evolution, creating a distinct collisional regime.
- The collisional regime's self-similar structures and the importance of bifurcation offer new insights into fluid mixing processes.
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