CONTINUOUS COUPLING OF CHAOTIC AND PERIODIC STATES OF CHEMICAL OSCILLATORS WITH AND WITHOUT TIME-DELAY

We present continuous coupling experiments and calculations of two mut ually flow-rate-coupled Belousov-Zhabotinsky (BZ) oscillators. The Ce4 +-concentration of one BZ-reactor controls the flow rate into the othe r BZ-reactor and vice versa. Flow-rate control is proportional to the difference between the (time delayed) Ce4+- and an average Ce4+-concen tration. When both period one (P1) BZ oscillators are weakly coupled, the P1 oscillations are retained in both oscillators whose periods inc rease with increasing coupling strength. At high coupling strengths st atistically aperiodic oscillations are produced. The introduction of t ime delayed coupling does not reduce the noise in the strongly coupled system. We distinguish between statistical aperiodicity due to experi mental noise and deterministic chaos due to the system's nonlinear dyn amics. At constant coupling strength a rising delay time produces a '' sawtooth'' like behaviour of the P1 periods. Mutual flow-rate-coupling of two chaotic states without time delay retains chaos in both reacto rs at low coupling strengths. When the coupling strength increases the Hausdorff dimension passes through a maximum (almost-equal-to 2.5). A t very high coupling strengths, a transition from chaos to periodic st ates takes place.