HYPERCHAOS AND CHEMICAL TURBULENCE IN ENZYMATIC REACTION-DIFFUSION SYSTEMS

We derive two kinetic models based on commonly occurring, simple enzym atic reactions. The first belongs to the class of activator-inhibitor models, whereas the second is a Selkov-type substrate-depletion model. The bifurcation behavior of both models is studied in a spatially hom ogeneous environment. We consider one-dimensional arrays of N oscillat ory reaction cells coupled by diffusion. For small N we find two kinds of hyperchaos depending on a bifurcation parameter and the ratio of t he diffusion coefficients of activator and inhibitor (D-a/D-i). For la rge N and D-a/D-i>1, we observe spatiotemporally chaotic states charac terized by phase defects. For D-a/D-i<1, we find a chemical turbulent state emerging from the interaction of a Hopf and a Turing instability in both models. (C) 1996 American Institute of Physics.