Study On Leak Detection Technology Of Pipeline Based On Transient Fluid Methods

The leak accidents in pipelines transportation not only cause great loss of material, but also pollute the environment. In recent years, in order to make sure that the pipelines can work safely and minimize the losses caused by leak accidents, it is necessary to study leak detection technology to raise the sensitivity of detection and accuracy of localization. Pipeline leak detection is a multi-field object, which includes many subjects, such as pipeline hydrodynamics, thermodynamics, sensor technology, subtle signal detection and signal processing. The pipeline leak detection and localization technology are studied in this dissertation.For the cause of a little leak, real time detection method of micro-dynamic signal is studied and the module between pressure and flux in the pipeline is put forward in this paper. Taken micro-dynamic signal into account, the answers of the flux and pressure equation in a long pipeline are worked out. Designing the procedure of micro-dynamic signal device is analyzed, controlled signal by software and hardware of the circuit is designed and is effected the beginning of the pipeline through transducer,electromotor and pumping station. The response of micro-dynamic signal in the pipeline is simulated.For the cause of much leak, the basis of instantaneous negative pressure wave to detect the pipeline leak is analyzed in this dissertation. The theory and advantage of the lifting wavelet transform is analyzed. Then, it is presented that the flow graph of obtaining the pipeline leak signal using the lifting wavelet and through practical ex- periments we get satisfied results.At last, it is worked out that the program of real time detection method based on micro-dynamic signal and instantaneous negative pressure wave method based on lifting wavelet transform by LabVIEW.