I will describe experiments on pattern formation in thermally driven
convection in an inclined, spatially extended fluid layer. Of particular
interest is the defect-turbulent state dubbed "undulation chaos." We
describe this state using both defect trajectories and local wavenumber
measurements. We characterize the ensemble of defect trajectories
according to their velocities, diffusion, and gain and loss rates.
In addition, for some parameter values the system displays competition
and bistability between ordered undulations and undulation chaos. The
transition to this competition is described in terms of the spatial
correlation length and the spectral entropy, which are found to be related
to defect density.
Audio requires RealPlayer by RealNetworks.
To begin viewing slides, click on the first slide below. (Or, view as pdf.)