Defect chaos and bursts: hexagonal rotating convection and the complex Ginzburg-Landau equation.
We employ numerical computations of the full Navier-Stokes equations to investigate non-Boussinesq convection in a rotating system using water as the working fluid. We identify two regimes. For weak non-Boussinesq effects the Hopf bifurcation from steady to oscillating (whirling) hexagons is supercritical and typical states exhibit defect chaos that is systematically described by the cubic complex Ginzburg-Landau equation. For stronger non-Boussinesq effects the Hopf bifurcation becomes subcritical and the oscillations exhibit localized chaotic bursting, which is modeled by a quintic complex Ginzburg-Landau equation.
Madruga
Santiago
S
Engineering Science and Applied Mathematics, Northwestern University, Evanston, Illinois 60208, USA.
Riecke
Hermann
H
Pesch
Werner
W