Linear and nonlinear hydromagnetic stability in laminar and turbulent flows
نویسندگان
چکیده
We consider the evolution of arbitrarily large perturbations a prescribed pure hydrodynamical flow an electrically conducting fluid. study whether as well generated magnetic fields decay or grow with time and constitute dynamo process. For that purpose we derive generalized Reynolds-Orr equation for sum kinetic energy hydrodynamic perturbation energy. The is confined in finite volume so normal component velocity at boundary zero. tangential left arbitrary contrast previous works. field mostly employ classical conditions where extends whole space. establish critical values Reynolds numbers below which initial decay. This involves generalization Rayleigh-Faber-Krahn inequality smallest eigenvalue elliptic operator. high number turbulence provide estimate fluctuations
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ژورنال
عنوان ژورنال: Physical review
سال: 2021
ISSN: ['0556-2813', '1538-4497', '1089-490X']
DOI: https://doi.org/10.1103/physreve.103.043104