Large - scale structure in Rayleigh - B enard convection withimpenetrable side - wallsRobert
نویسندگان
چکیده
In numerical Rayleigh-B enard convection at Rayleigh number 10 5 and 5 10 5 , Prandtl numbers 0.07, 0.7, and 7, and aspect ratios 3, 4 or 6, large-scale patterns are sought. For aspect ratio 6 and P r = 0:7, saturation of the mean velocity is only observed after 20 convective timescales. Three-dimensional visualization shows a strong innuence of the connning sidewalls and corners for all Prandtl numbers. Sweeping motions are observed for P r = 7.
منابع مشابه
Asymptotic Behavior of the Global Attractors to the Boussinesq System for Rayleigh-B enard Convection at Large Prandtl Number
We study asymptotic behavior of the global attractors to the Boussinesq system for Rayleigh-B enard convection at large Prandtl number. In particular, we show that the global attractors to the Boussinesq system for Rayleigh-B enard convection converge to that of the in nite Prandtl number model for convection as the Prandtl number approaches in nity. This o ers partial justi cation of the in ni...
متن کاملSpiral dynamics in pattern - forming systems : mean - ow e ects
Meanow e ects are discussed for two di erent pattern-forming systems: Rayleigh–B enard convection and Faraday instability in viscous uid. In both systems spirals are observed in certain parameter regions. In the Rayleigh–B enard convection, the spiral-core instability is shown to occur due to the mean ow generated by the curved rolls near the core. In the Faraday instability, the mean ow which ...
متن کاملNovel Convective Instabilities of Low- to Moderate-prandtl Number Fluids
LOWTO MODERATE-PRANDTL NUMBER FLUIDS Guy Metcalfe Division of Building, Construction and Engineering CSIRO Highett, Victoria AUSTRALIA R.P. Behringer Dept. of Physics and Center for Nonlinear and Complex Systems Duke University Durham, North Carolina USA to be given at the 12th Australasian Fluid Mechanics Conference, Sydney Australia December 10{15 1995 ABSTRACT Super uid mixtures have Prandtl...
متن کاملTransition between curved and angular textures in binary fluid convection.
We report a transition from a curved texture to an angular texture in Rayleigh-B enard convection in a mixture of ethanol and water. The transition occurs as the Rayleigh number is reduced from a high value and approaches the traveling-wave branch and is observed at negative values of the separation ratio in uid mixtures, but not in a pure uid. We show that this transition may be understood in ...
متن کاملImplicit Time Splitting for Fourth - Order ParabolicEquationsC
A coordinate-splitting economic diierence scheme is proposed for generalized parabolic equations (GPE) containing fourth-order diiusion operators and the algorithm for its implementation is developed. The performance of the scheme is demonstrated for diierent cases, e.g. for treating bifurcation phenomena. The technique is applied to the numerical solution of Swift-Hohenberg equation describing...
متن کامل