Spatiotemporal patterns in the Bär model induced by concentration-depedent diffusivities.

PAULA BERGERO; ISABEL MARÍA IRURZUN; EDUARDO ELÍAS MOLA

CHEMICAL PHYSICS LETTERS

Elsevier

Año: 2007 vol. 445 p. 151 - 161

0009-2614

                                              We investigate the effects of diffusivity on pattern formation in the excitable regime of the Bär model,  in 2D. Our study mainly focusses on the turbulent states, including the breakdown spiral process. Both linearly and quadratically dependent diffusion coefficient on the activator concentration were studied. Inhibition of the spiral instability can be found with a negative linear coefficient in the concentration dependence of the diffusion coefficient. Depending on the boundary conditions, the inhibition can be completed (nonflux boundary conditions) or just delayed (periodic boundary conditions). The chaotic zone is not qualitatively modified. Positive quadratic coefficients in the concentration dependence of thediffusion coefficient strongly modify the defect statistic in the chaotic zone.