Stochastic resonance at nonequilibrium phase transitions

Thermal pulsations in a transition from a nucleate to a film regime of water boiling on a wire heater with a periodic Joule heat release have been studied experimentally. At frequencies of the periodic action smaller than 0.1 Hz the intermittency of the nucleate and film boiling regimes was observed. In this case the amplitude of thermal pulsations increased. The experiments with an additional noise source were carried out. With an increase in the intensity of the noise the power of the output periodic mode increased and reaching the maximum began to decrease. The results are interpreted as stochastic resonance when the periodic component of pulsations increases in the presence of noise. The results show that in a complex system with nonequilibrium phase transitions there can occur both the extreme fluctuations with 1/f power spectrum and stochastic resonance under external periodic action.