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Title: Algebraic bounds on the Rayleigh–Bénard attractor
Abstract The Rayleigh–Bénard system with stress-free boundary conditions is shown to have a global attractor in each affine space where velocity has fixed spatial average. The physical problem is shown to be equivalent to one with periodic boundary conditions and certain symmetries. This enables a Gronwall estimate on enstrophy. That estimate is then used to bound the L 2 norm of the temperature gradient on the global attractor, which, in turn, is used to find a bounding region for the attractor in the enstrophy–palinstrophy plane. All final bounds are algebraic in the viscosity and thermal diffusivity, a significant improvement over previously established estimates. The sharpness of the bounds are tested with numerical simulations.
Authors:
; ; ;
Award ID(s):
1818754
Publication Date:
NSF-PAR ID:
10337299
Journal Name:
Nonlinearity
Volume:
34
Issue:
1
Page Range or eLocation-ID:
509 to 531
ISSN:
0951-7715
Sponsoring Org:
National Science Foundation
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