Radial boundary layer structure and Nusselt number in Rayleigh–Bénard convection
نویسندگان
چکیده
منابع مشابه
Radial boundary layer structure and Nusselt number in Rayleigh-Bénard convection
Results from direct numerical simulations for three dimensional Rayleigh-Bénard convection in a cylindrical cell of aspect ratio 1/2 and Pr = 0.7 are presented. They span five decades of Ra from 2× 10 to 2× 10. Good numerical resolution with grid spacing ∼ Kolmogorov scale turns out to be crucial to accurately calculate the Nusselt number, which is in good agreement with the experimental data b...
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We present high-precision measurements of the Nusselt number N as a function of the Rayleigh number R for a cylindrical sample of water (Prandtl number sigma=4.4) of height L approximately equal to 50 cm and aspect ratio Gamma identical with D/L approximately equal to 1 (D is the diameter) for 3 x 10(9)< or =R< or =6 x 10(10). For R approximately 3 x 10(9) the data are consistent with existing ...
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Rayleigh-Bénard convection is the buoyancy-driven flow of a fluid heated from below and cooled from above. This model of thermal convection is a paradigm for pattern formation and turbulence [1] and it plays an important role in a large range of phenomena in geophysics, astrophysics, meteorology, oceanography and engineering. The problem under investigation is: given an incompressible fluid enc...
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We present an experimental study of the spatial structure of the velocity field in the boundary layer region of a Rayleigh-Bénard convection cell, using water as the working fluid. Our results show that the mean flow, the shear rate, and the viscous boundary layer thickness all change significantly across the conducting horizontal surface of the cell. Moreover, the measurements reveal that the ...
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ژورنال
عنوان ژورنال: Journal of Fluid Mechanics
سال: 2010
ISSN: 0022-1120,1469-7645
DOI: 10.1017/s0022112009992461