Almeida Fabrício, Brennan Michael, Joseph Phillip, Whitfield Stuart, Dray Simon, Paschoalini Amarildo
Department of Mechanical Engineering, UNESP - FEIS, Av. Brasil, 56, 15385-000, Ilha Solteira, Brazil.
Institute of Sound and Vibration Research-ISVR, University Road, SO17 1BJ, Southampton, UK.
Sensors (Basel). 2014 Mar 20;14(3):5595-610. doi: 10.3390/s140305595.
Acoustic techniques have been used for many years to find and locate leaks in buried water distribution systems. Hydrophones and accelerometers are typically used as sensors. Although geophones could be used as well, they are not generally used for leak detection. A simple acoustic model of the pipe and the sensors has been proposed previously by some of the authors of this paper, and their model was used to explain some of the features observed in measurements. However, simultaneous measurements of a leak using all three sensor-types in controlled conditions for plastic pipes has not been reported to-date and hence they have not yet been compared directly. This paper fills that gap in knowledge. A set of measurements was made on a bespoke buried plastic water distribution pipe test rig to validate the previously reported analytical model. There is qualitative agreement between the experimental results and the model predictions in terms of the differing filtering properties of the pipe-sensor systems. A quality measure for the data is also presented, which is the ratio of the bandwidth over which the analysis is carried out divided by the centre frequency of this bandwidth. Based on this metric, the accelerometer was found to be the best sensor to use for the test rig described in this paper. However, for a system in which the distance between the sensors is large or the attenuation factor of the system is high, then it would be advantageous to use hydrophones, even though they are invasive sensors.
声学技术多年来一直被用于查找和定位埋地供水系统中的泄漏点。水听器和加速度计通常用作传感器。虽然地震检波器也可以使用，但它们一般不用于泄漏检测。本文的一些作者之前曾提出过一个简单的管道和传感器声学模型，他们的模型用于解释测量中观察到的一些特征。然而，迄今为止，尚未有在受控条件下对塑料管道同时使用这三种传感器类型进行泄漏测量的报道，因此它们尚未得到直接比较。本文填补了这一知识空白。在一个定制的埋地塑料供水管道试验台上进行了一系列测量，以验证先前报道的分析模型。就管道 - 传感器系统不同的滤波特性而言，实验结果与模型预测之间存在定性的一致性。还提出了一种数据质量度量方法，即进行分析的带宽与该带宽中心频率的比值。基于此指标，发现加速度计是本文所述试验台的最佳传感器。然而，对于传感器之间距离较大或系统衰减系数较高的系统，使用水听器会更具优势，尽管它们是侵入式传感器。
