Lu Ping, Chen Shuang, Sheng Xiaozhen, Gao Yan
State Key Laboratory of Traction Power, Southwest Jiaotong University, Chengdu 610031, China.
Rail Transit College, Chengdu Vocational& Technical College of Industry, Chengdu 610213, China.
Sensors (Basel). 2022 May 23;22(10):3942. doi: 10.3390/s22103942.
The time-delay estimation (TDE) method is the primary method for predicting leakage locations in buried water distribution pipelines. The accuracy of TDE depends on the acoustic speed and attenuation of the leakage signal propagating along the pipeline. The analytical prediction model is the typical approach for obtaining the propagation speed and attenuation of leakage waves. However, the embedding parameters of the buried pipe in this model must be measured using soil tests, which are very difficult, costly, and time-consuming. These factors restrict the application of the TDE method in pinpointing pipeline leakage. A method for inverse identification of pipe embedding parameters using discrete wavenumbers obtained in field testing is presented in this paper, and the differential evolution algorithm is introduced as an optimization solution. A field experiment is conducted to validate the method, and the test wavenumbers are measured in a cast-iron pipeline. The estimated sensitive parameters in the analytical model using the method are soil elastic modulus, Poisson's ratio, and pipe-soil contact coefficient, while the conventional soil test is used to measure the soil density due to the character of the optimization algorithm and the soil properties. The application effects show that the estimated parameters are close to those measured from a conventional soil test. The wave speed based on the estimated parameters was an excellent match for the on-site test in the engineering application. This work provides a less costly and more straightforward way to apply the TDE method for leak localization in buried pipelines.
时延估计（TDE）方法是预测埋地输水管道泄漏位置的主要方法。TDE的准确性取决于沿管道传播的泄漏信号的声速和衰减。解析预测模型是获取泄漏波传播速度和衰减的典型方法。然而，该模型中埋地管道的埋设参数必须通过土工试验来测量，这非常困难、成本高昂且耗时。这些因素限制了TDE方法在精确确定管道泄漏位置方面的应用。本文提出了一种利用现场测试中获得的离散波数对管道埋设参数进行反识别的方法，并引入差分进化算法作为优化求解方法。进行了现场试验以验证该方法，并在铸铁管道中测量了测试波数。使用该方法在解析模型中估计的敏感参数为土壤弹性模量、泊松比和管土接触系数，而由于优化算法的特性和土壤性质，传统土工试验用于测量土壤密度。应用效果表明，估计参数与传统土工试验测量的参数接近。基于估计参数的波速在工程应用中与现场测试结果匹配良好。这项工作为将TDE方法应用于埋地管道泄漏定位提供了一种成本更低、更直接的方法。
