Computational Fluid Dynamics
Institut für Geophysik
Convection is an ubiquitous phenomenon which occurs in the atmosphere, the
oceans, the interior of the Earth, and in numerous engineering applications.
Convection has also served as a paradigm for pattern forming systems because the
flow can organize itself into rolls or polygonal structures. It is not known how
the large scales of convection are organized once the flow has become turbulent.
This project intends to study the large scale patterns which persist in the
turbulent regime. Convection in a plane layer will be simulated within the
Boussinesq approximation. Quantities extracted from the computations will
include the Nusselt number, the Reynolds number, and the spectral distributions
of heat transport and kinetic energy.
The equations of motion are solved with a spectral method. The velocity field is
decomposed into poloidal and toroidal scalars in order to automatically obtain a
divergence free velocity field. The spectral decomposition uses Fourier modes
and Chebychev polynomials.