Re-entrant hexagons in non-Boussinesq convection
نویسندگان
چکیده
منابع مشابه
Reentrant Hexagons in non-Boussinesq Convection
While non-Boussinesq hexagonal convection patterns are well known to be stable close to threshold (i.e. for Rayleigh numbers R ≈ Rc), it has often been assumed that they are always unstable to rolls already for slightly higher Rayleigh numbers. Using the incompressible Navier-Stokes equations for parameters corresponding to water as a working fluid, we perform full numerical stability analyses ...
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We study hexagon patterns in non-Boussinesq convection of a thin rotating layer of water. For realistic parameters and boundary conditions we identify various linear instabilities of the pattern. We focus on the dynamics arising from an oscillatory side-band instability that leads to a spatially disordered chaotic state characterized by oscillating (whirling) hexagons. Using triangulation we ob...
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We review recent computational results for hexagon patterns in nonBoussinesq convection. For sufficiently strong dependence of the fluid parameters on the temperature we find reentrance of steady hexagons, i.e. while near onset the hexagon patterns become unstable to rolls as usually, they become again stable in the strongly nonlinear regime. If the convection apparatus is rotated about a verti...
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ژورنال
عنوان ژورنال: Journal of Fluid Mechanics
سال: 2006
ISSN: 0022-1120,1469-7645
DOI: 10.1017/s0022112005007640