Different Kinds of Chaotic Oscillations in the Belousov-Zhabotinskii Reaction

Abstract

Abstract Following earlier evidence for chaotic time behaviour in the open flow continuous stirred Belousov-Zhabotinskii reaction based on a single measured observable, now two-dimensional phase plots are presented. The potential of a bromide ion sensitive electrode was plotted against the electrochemical potential. In the two-dimensional observation space obtained, both apparent limit cycle oscillations and apparent chaotic oscillations were observed. Of the latter, type 1 resembles a double-limit cycle system with fluctuation-triggered transitions between the two regimes (exogenous chaos); type 2 is analogous, but here the irregular transition between the two oscillatory regimes gives the impression of being, in principle, independent of exogenous noise. If so, this flow may be related to one of the chaotic flows with saddle point known (for example, the Lorenz attractor). Type 3, only observed as a transient so far, looks like a two-dimensional projection of screw type chaos, which is one of the simplest types of deterministic chaos. Type 4 corresponds either to a fluctuation-triggered monoflop (exogenous chaos) or to folded-strip (spiral) type chaos.