【摘要】 分析了小流量涡街信号特性,探讨了信号与随机共振系统的阈值和克莱默斯逃逸率之间的关系,提出一种基于幅值和频率双重调制的随机共振方法,用于检测小流量涡街信号的频率。该方法以外加控制信号的幅值和频率作为调控变量,采用多参数控制方式使小流量涡街信号产生随机共振。经数值仿真及实验研究,表明该方法能将小流量涡街信号通过随机共振得到增强,有效获取涡街频率,实现小流量测量,为随机共振的控制和微弱信号的检测提供一种新方法。更多还原

【Abstract】 The characteristics of lower flowrate vortex signal was analyzed in this paper,and the relationship between the signal and the stochastic resonance system from two aspects of threshold value and Kramers rate was discussed. A stochastic resonance method based on amplitude and frequency double-modulation was presented to detect the frequency of lower flowrate vortex signal. The multiple parameters control method based on amplitude and frequency of external control signal was used for lower flowrate vortex signal to generate stochastic resonance. The numerical simulation and experimental research manifest that the method can enhance the lower flowrate vortex signal and effectively obtain the frequency of vortex shedding for lower flowrate measurement. The method provides a new way for stochastic resonance control and weak signal detection.更多还原