宽频高幅值水力激振信号的产生与控制

Creation and control of hydraulic vibration signal with wide frequency range and high amplitude

为了研究火箭发动机全尺寸泵后供应系统的动力学特性,运用脉动压力发生器设计了一种宽频水力激振系统,开展了液流试验和数据分析。结果表明:水力激振系统可以在0~1 200Hz的频率范围内,产生时域幅值超过1.5MPa、高信噪比的压力脉动信号,达到了宽频率范围、高激励幅值的目的。通过对电动机转速的控制实现激励频率的可控变化,以满足不同频率激励策略的要求。提高管路系统的入口稳态压力,可以提高激振信号的幅值。通过合适的局部流阻分布,可以在宽频范围内提高水力激振信号的幅值,提高信噪比。

A hydraulic vibration system with wide frequency range was designed by using the pulsation generator,in order to study the dynamical characteristics of the full scale propellant feed system after the pump in the liquid rocket engine,and the cold fluid tests and data analysis were conducted.Within the range of 0-1 200 Hz,the hydraulic vibration system can create pressure fluctuation signal with amplitude more than 1.5 MPa and high signalto-noise ratio.The target of wide frequency range and high amplitude was reached.By controlling the electric motor revolving speed,the controlled excitation frequency can be realized to satisfy different frequency actuating methods.Increasing the system inlet steady pressure can improve the hydraulic vibration signal amplitude.By appropriately distributing local resistors,the hydraulic vibration signal amplitude and signal-to-noise ratio can be improved within widefrequency range.