Spatially growing waves, intermittency, and convective chaos in an open- flow system
We study a model open-flow system: the time-dependent generalized Ginzburg-Landau equation under conditions when it is convectively (i.e. spatially) unstable. In the presence of low-level external noise, this system exhibits a selective spatial amplification of noise resulting in spatially growing waves. Three distinct spatial regions are found: 1) A linear region in which spatially growing waves are formed; 2) a transition region characterized by the transition from the spatially growing wave frequencies of the linear region to the turbulent frequencies of the fully developed region; and 3) a fully developed region in which the nonlinear dynamics dominates. In the transition region, the microscopic noise plays an important role in the macroscopic dynamics of the system. In particular, the external noise initiates the transition to turbulence and is responsible for the intermittent turbulent behavior observed in the transition region. Power spectra and correlation functions are calculated and analytical expressions are derived for these quantities in the linear region. Similarities between this system and fluid systems are discussed. Also, a few analytical results for coupled-map lattices are derived.
time-dependent generalized Ginzburg-Landau equation
linear region to the turbulent frequencies
scientific article; zbMATH DE number 3988956
scientific article