噪声在外加周期信号控制强湍中的作用研究

研究了噪声在控制中的作用.研究发现，较小强度的偏噪声信号能够使系统失去层流态，重新进入无序态，此时模式之间的广义相同步也失去了；而噪声强度较大时，系统则能够维持准周期的层流态，模式相位之间依然能够达到广义相同步. 关键词： 相同步 时空混沌 湍流 非线性漂移波

Effect of noise in controlling strong turbulence by external periodic signal

Strong turbulence in the driven drift-wave equation of plasma can be suppressed successfully to a laminar flow by an external periodic signal with proper frequency and strength. In the driving wave coordinates，by transforming the wave system to a set of coupled oscillators (modes) moving in a periodic potential，generalized phase synchronization between these modes is regarded as one of the control mechanisms. In this paper，the effect of noise is studied in the course of the turbulence control. It is found that the laminar flow becomes disordered again with fairly weak bias noise，at the same time the generalized phase synchronization between the modes is lost. However，when the bias noise is quite strong，the quasi-period laminar state can be maintained and the modes can also reach generalized phase synchronization with each other.