Two-parameter stochastic resonance in the absence of external signal for the photosensitive Belousov-Zhabotinsky reaction

摘要

Stochastic resonance (SR) is studied numerically in a modified Oregonator-type model, which was proposed recently to account for the photosensitivity of the Belousov-Zhabotinsky (BZ) reaction in a flow system. When either of the two control parameters, light flux and a flow rate, is modulated by multiplicative external noise, noise induced coherent oscillations (NICO) in the absence of deterministic oscillations are observed near Hopf bifurcation point, where the external noise is added to one parameter or the other. The signal-to-noise ratio (SNR) goes through a maximum with the increment of noise intensity indicating occurrence of SR. The aspects of the two-parameter SR in this system are discussed.