Investigation Of Leak Detection And Location System For Water Pipeline Based On Acoustic Signal

The route of city water supply pipeline is complex, wide distribution, and has long transport distance. Pipeline leakage accidents often occur under the condition of natural aging, corrosion and other non-artificial factors. However, the efficiency of traditional artificial way to find leakage position is low, and often causes serious waste of resources and economic losses because of fails to take timely measures for leakage accident. Therefore, how to quickly find out the pipeline leakage position, implement on-line detection and location of leakage has become now a very urgent subject.According to the actual operation of the environment, the existing pipeline leak detection methods are analyzed, and it makes a way of pipeline leak detection based on acoustic signal, the traditional methods of pipeline leakage detection positioning often lead to the problem of low positioning precision, which is based on double sensors in the sound velocity using experience value fixed input, the new method uses the on-site real-time detection, which builds a pipeline leak detection based on three sensor positioning model. Research the time-frequency characteristics of acoustic signal under the five kinds of working conditions like different pipeline material, different pipeline pressure, different acoustic signal propagation distance, different leakage diameter, different pipeline interface material, and analyze the attenuation characteristics and propagation characteristic of pipeline leakage acoustic signal.The paper analysis the principle of the existing least mean square LMS adaptive time delay estimation algorithm, according to the issue that step factor reduces quickly when the algorithm convergence degree deepen, the sum of forgetting weighted for historical error square and sliding window are introduced to improve the iterated function of step factor, and improve the performance of time delay estimation algorithm.Several parts of the system hardware are designed, including signal processing circuit, AD conversion module, GPS time service module, GPRS data transmission module, power module and DSP minimum system, etc. VC++ and MATLAB mixed programming method is adopted to develop the PC software.This paper taking leakage location model which based on three sensors as a hardware experiment platform for water supply pipeline network, and test the pipeline leak detection and location performance combine with the PC software. The test result shows that the system can correctly detect the leakage signal incorrectly, and the leak location accuracy is higher, which meets the needs of actual production.