Spontaneous Spiral Formation in Two-Dimensional Oscillatory Media

Computational studies of pattern formation in a modified Oregonator model of the Belousov-Zhabotinsky reaction is described. Initially inactive two-dimensional reaction media with an immobilized catalyst is connected to a reservoir of fresh reactants through a set of discrete points distributed randomly over the interphase surface. It is shown that the diffusion of reactants combined with oscillatory reaction kinetics can give rise to spontaneous spiral formation and phase waves.

Fig. 1. Two-dimensional simulations of pattern formation with varying open diffusion site probabilities. Two images are shown for each example. The left-hand images show the dimensionless concentrations of the propagator u with white mapped to the highest value and black assigned to the steady-state value. On the right, black indicates the open diffusion sites.