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α effect in three-dimensional vortex of conducting rotating liquid
L L Ogorodnikov1, S S Vergeles1
1<a href="https://ror.org/00z65ng94">Landau Institute for Theoretical Physics</a>, Russian Academy of Sciences, 1-A Akademika Semenova av., 142432 Chernogolovka, Russia and <a href="https://ror.org/055f7t516">National Research University Higher School of Economics</a>, Faculty of Physics, Myasnitskaya 20, 101000 Moscow, Russia.
Physical Review. E
|December 18, 2024
Summary
This study analyzes helical turbulent flow statistics in rotating fluids. We found the alpha-effect
Area of Science:
- Fluid dynamics
- Magnetohydrodynamics
- Turbulence theory
Background:
- Investigating helical turbulent pulsations within a rotating fluid's large-scale vortex.
- Considering helical flow generated by a statistically axially symmetric random force with broken mirror symmetry.
Purpose of the Study:
- To analytically calculate velocity-vorticity mean, magnitude, and anisotropy.
- To examine the alpha-effect in electrically conducting liquids.
- To determine the influence of Rossby (Ro) and magnetic Prandtl (Pr_m) numbers on the alpha-effect.
Main Methods:
- Analytical calculation of one-point statistics for helical turbulent pulsations.
- Analysis of the alpha-effect in a rotating fluid system.
- Investigating the dependence of alpha-matrix elements on Ro and Pr_m numbers.
Main Results:
- The velocity-vorticity mean, its magnitude, and anisotropy were analytically calculated.
- The alpha-effect in electrically conducting liquids was examined.
- Alpha-matrix elements show strong dependence on the relation between Rossby and magnetic Prandtl numbers (Ro << 1, Pr_m << 1).
Conclusions:
- A criterion was established for when the alpha-effect induces instability in large-scale magnetic fields.
- The findings are crucial for understanding turbulence and magnetic field generation in rotating systems.
- The study highlights the critical role of fluid properties and rotation in magnetohydrodynamic phenomena.
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