关键词: 流量调节器;管路;频率特性;稳定性

Abstract: A frequency-domain analytical model of one flow regulator-pipe system was developed to describe its dynamic characteristics. The system frequency response to inlet pressure disturbance and the system stability was investigated. The results show that, the resonance frequencies of the system represent the acoustic characteristics of the pipe, and the movement of the slider enlarges the resonance amplitude. By analyzing the system complex natural frequency at different parameters, the variable rule of the system stable boundary according to the inlet resistance was presented. It shows that, as the inlet resistance increasing from zero to the matching resistance, the unstable region of the system reduced continually, and disappeared after the inlet resistance exceeding one value. The mechanism of system instability is that, the regulator works as a negative resistance component at a frequency range, which becomes the unstable frequency region when the negative resistance effect of the regulator exceeds the inlet resistance dissipation. And if the system natural frequency determined by the pipe length was in the unstable frequency region, then the instability takes place at the natural frequency. 

Key words: Flow regulator; Pipe; Frequency characteristics; Stability