压电式加速度计在供水管道泄漏定位中的应用

Application of piezoelectric accelerometers in water pipeline leak locating

供水管道发生泄漏时,泄漏噪声在管道内的水中传播,由于流固耦合作用引起管壁的径向振动。选择合适的压电式加速度计,并正确地安装在管道上,可以检测到微弱的管壁振动。将2个压电式加速度计放在漏点两侧的管道暴露点上,用相关分析的方法得到泄漏噪声到达2个传感器的时间差,根据时间延迟、泄漏噪声传播速度和2个传感器距离之间的关系估计泄漏的位置,相对误差在5%以内,与人工听漏相比,提高了定位的效率。

Leaks from water supply pipesgenerate noise. The noise propagates in the water column of pipeline. Due to fluid-structure interaction, water-borne noise induces radial vibration of pipe wall. Piezoelectric accelerometer can test the weak vibration by the appropriate selection and installation. Noise signals are measured using accelerometers at two access points of pipeline on either side of the location of a suspected leak. The timedifference of leak signals is estimated by correlation analysis. The location of the leak is calculated using a algebraic relationship between the time delay,the noise propagation speed and the distance between two sensors. Relative errors of pinpointing are below 5 %. Comparing with the conventional listening inspection, the efficiency of leak locating is improved.