Collect. Czech. Chem. Commun. 1998, 63, 761-769

Stabilization of Dominant Structures in an Ionic Reaction-Diffusion System

Roland Krämer and Arno F. Münster

Institute of Physical Chemistry, University of Würzburg, Am Hubland, D-97074 Würzburg, Germany


We describe a method of stabilizing the dominant structure in a chaotic reaction-diffusion system, where the underlying nonlinear dynamics needs not to be known. The dominant mode is identified by the Karhunen-Loeve decomposition, also known as orthogonal decomposition. Using a ionic version of the Brusselator model in a spatially one-dimensional system, our control strategy is based on perturbations derived from the amplitude function of the dominant spatial mode. The perturbation is used in two different ways: A global perturbation is realized by forcing an electric current through the one-dimensional system, whereas the local perturbation is performed by modulating concentrations of the autocatalyst at the boundaries. Only the global method enhances the contribution of the dominant mode to the total fluctuation energy. On the other hand, the local method leads to simple bulk oscillation of the entire system.

Keywords: Control of chaos; Orthogonal decomposition; Spatiotemporal patterns.