摘要
相关仪利用供水管道泄漏时产生的泄漏声波对漏点定位。泄漏信号验证为高斯分布,泄漏声波主要是在管道里的水中传播,与管壁发生流固耦合作用,引起管壁振动。用FIR滤波器对管道系统建模,采用最小均方误差(LMS)自适应系统辨识方法得到管道的冲激响应函数,与线性相位FIR滤波器的冲激响应相比较,表明泄漏声波在传播过程中存在频散。泄漏声信号受各种噪声干扰,根据互谱相位谱信息估计泄漏信号的频带范围,对信号滤波后作时延估计,结果表明,提高了泄漏定位的置信度。
Leaks in water supply pipelines cause waste of precious resources and endanger the environment. Correlator pinpoints leaks depending on the noise from the leaks. The leakage noise meets Gaussian distribution. The fluid-filled pipe is considerably complicated due to fluid-structure interaction. The radial pipe wall vibration is excited by internal water pressure pulsations arising from water-borne sound. The pipeline system is supposed to be a finite impulse response （FIR） system. Adaptive system identification technique employing least-mean-square （LMS） algorithm is applied to modelling the pipeline and analyzing the propagation characteristics of leak noise. Signal dispersion is observed corresponding to the significant asymmetry displayed by the impulse response of the pipeline. Basing on cross-power spectrum phase, the frequency band of leak signal is obtained. The filtered signals are used in the estimation of time delay. It is indicated that the method improves confidence of locating leak.
出处
《声学技术》
CSCD
北大核心
2007年第5期871-876,共6页
Technical Acoustics
关键词
泄漏定位
时延估计
振动
流固耦合
自适应系统辨识
互谱
leakage location
time delay estimation
vibration： fluid-structure interaction
adaptive systemidentification
cross-power spectrum
