Research On Leak Detection And Location System In Urban Water Supply Network

The safe and high quality of urban water supply relate to the development of the national economy and the people's livelihood.Therefore, to carry out water pipeline leak detection, research and establish a simple and user-friendly pipeline leak detection and location system has extremely important practical significance.In this thesis, the research background is the leak detection and location for actual water supply pipelines. The main research is focus on the leak signal acquisition and signal processing technologies in the laboratory environment, and on this basis, a complete set of leak detection and location system is established. Our research group has developed a special sensor probe for water pipeline leak detection in the previous. Based on this, this thesis has a groundbreaking study in both signal acquisition and signal processing technologies. LabVIEW was used to build a set of powerful, extended, high accuracy positioning of the leak detection software system, it provides a good template for the laboratory to build its data acquisition system.First of all, a detailed analysis of the development of leak detection technology both at home and abroad is given. The knowledge of leak signal and its transmission characteristics is obtained, on this basis a pipeline leak signal propagation model was built, provided a theoretical basis for signal analysis and processing.And then, research and design a data acquisition system for leak detection and location is discussed. Analysis the factors that influence the data acquisition, and thus select the appropriate sensors, signal conditioning equipment, as well as data acquisition card to build experimental system.Next, an in-depth study was made on the leak signal processing methods, and comprehensive utilization of random time-frequency analysis, power spectrum analysis, wavelet transform de-noising method and correlation analysis and other modern signal processing methods on the actual status of pipeline leak detection, experimental results show that these signal processing methods have the ability and reliable identification of a leakage even when its small.Finally, a detailed study is focus on the use of virtual instrument technologies in the application of water supply pipe network leakage detection areas. This thesis combines the practical needs designs a compatibility strong and high accurate of the water supply pipe network leak detection and location software system. On the base of this, the leakage identification on the experimental research shows that the software system has good stability, with strong analytical capabilities, as well as leak point positioning capability.