XXI ICTAM, 15–21 August 2004, Warsaw, Poland NONLINEAR CONVECTIVE PATTERNS IN SPHERICAL RAYLEIGH-BÉNARD SYSTEMS
نویسندگان
چکیده
Nonlinear thermal convection in a spherical fluid layer in the presence of spherically symmetric gravity, spherical RayleighBénard convection, is investigated. At the onset of spherical Rayleigh-Bénard convection, there exists the (2l+1)-fold degeneracy of the linear solution, where l is the degree of a spherical harmonics. Nonlinear convection is studied through fully three-dimensional numerical simulations. Several new spherical patterns of nonlinear convection are found. In particular, a steadily drifting pattern in the form of a single giant spiral roll covering the whole spherical surface without defects is discovered for various Prandtl numbers for the first time.
منابع مشابه
XXI ICTAM, 15–21 August 2004, Warsaw, Poland LARGE EDDY SIMULATION OF RAYLEIGH-BÉNARD CONVECTION IN AN INFINITE FLUID LAYER
A numerical study of Rayleigh-Benard convection in an infinite fluid layer (Pr=0.71) is performed using large eddy simulation (LES) of the Navier-Stokes equations with the Boussinesq approximation. We present results in the ’hard turbulence’ regime (2.10 < Ra < 2.10). The LES modelling uses the mixed scale diffusivity model, that we have originally developed in the case of the differentially he...
متن کاملXXI ICTAM, 15–21 August 2004, Warsaw, Poland ATTRACTOR AND PATTERN CONTROL IN NONLINEAR MEDIA BY LOCALIZED DEFECTS
We consider pattern and attractor control in nonlinear dissipative systems. We develop an analytic approach to attractor control for neural, genetic networks systems of coupled oscillators and spatially extended systems. In particular, we apply this method for some systems of Ginzburg-Landau’s type and others.
متن کاملXXI ICTAM, 15-21 August 2004, Warsaw, Poland SIMULATION OF CONTACTING SPATIAL POLYHEDRAL PARTICLES
In the following, the collective dynamical behaviour of many convex and non-convex polyhedral bodies in space is described. To be able to simulate a high number of bodies, methods from Molecular Dynamics (MD) are frequently used. Here these methods are combined with collision detection methods and contact formulations adopted from Multibody Systems (MBS). The used methods are presented briefly ...
متن کاملXXI ICTAM, 15–21 August 2004, Warsaw, Poland INERTIAL MIGRATION OF RIGID SPHERICAL PARTICLES IN POISEUILLE FLOW
A neutrally buoyant particle in pipe flow is known to undergo a radial migration for finite Reynolds number flows. This effect was first observed by Segré and Silberberg (1962), who noted a radial equilibrium position at a radius r = 0.6R in a pipe of radius R, in conditions of finite but low Re. These results have been extended to show that the equilibrium position of the particles is moved to...
متن کاملXXI ICTAM, 15–21 August 2004, Warsaw, Poland IDENTIFICATION OF SOME CHEMOPOROELASTIC PARAMETERS OF A REACTIVE SHALE FROM EXPERIMENTAL DATA
This paper is concerned with the experimental identification of some chemoporoelastic parameters of a chemically reactive shale from data obtained in pore pressure transmission-chemical potential tests. The parameter identification is carried out by matching the observed pressure response with a theoretical solution of the experiment. This solution is obtained within the framework of Biot theor...
متن کامل