Pipeline Leak Monitoring And Location Technology Research

The safety of pipeline transportation is an important subject in pipelinetransportation, so a variety of pipeline leakage detection technology emerge. Inrecent years, with the rapid development of sensor technology, embeddedtechnology and computer technology, the intelligent systems of pipeline leakagebased on sensor array become popularization. Infrasound detection method issuitable for gas pipeline leakage detection because of the particularity ofmedium in pipeline and the acoustic characteristics. Many of sensors foracoustic detection method are the pressure transmitter, which have a lowsensitivity to acoustic wave; And the development of infrasound sensors aremostly used in atmospheric environment at home and abroad, little specificallyfor high-pressure gas pipeline. Besides, although the present detection methodsimprove the calculation of acoustic propagation speed in pipes and denoisingmethods, but there are two problems: low positioning accuracy because of theacoustic wave propagation velocity uncertainty, not being able to locate aplurality of leakage points at the same time. So the development of infrasonicsensor for gas pipeline is an important basis for infrasound detection method.How to obtain the real-time propagation speed of sound wave in actual pipelineand being able to locate a plurality of leak is an important content of research onacoustic detection method.The dissertation is aimed at studying the two problems of the actual demandof gas pipeline leak detection system. The main results of this research can besummarized as follows:1、 The model of acoustic wave generated by pipeline leakage andpropagation model is simulated. The simulation results show that: the acousticfrequency produced in the leak start stage is mainly in the low frequency part;the propagation attenuation of low frequency acoustic wave is smaller than highfrequency sound wave.2、A infrasonic sensor suitable for high-pressure gas pipeline leak detectionis developed. Aiming at low sensitivity of pressure transmitter to acoustic wave, the sensor’s sensitive element is a kind of condenser infrasound sensor., whichhas good anti-interference performance of vibration and is only sensitive tosound wave; In allusion to high-pressure gas pipeline, it has a greatimprovement in Structure design and preamplifier design, which ensures thesensor suitable for high-pressure gas pipeline. Finally, we tested and recalibratedthe sensor, and then confirmed its performance parameters.3、A new leak positioning algorithm is proposed. Aiming at the problem oflow location accuracy, the speed of sound wave propagation in the pipe iscalculated by correlation algorithm; In allusion to not being able to locatemultiple leakage point on gas pipeline, the extended use of beamforming basedon linear array model allows us to see the acoustic field in pipes, which doesn’tonly have a good anti-interference, but also realizes visualization analysis ofacoustic field in pipe, so as to be able to locate a plurality of leak points at thesame time. Computer simulation results for the methods show that the algorithmcan locate multiple leakage points accurately.4、Based on the sensor and the algorithm, an extensible system of infrasonicsensor network is designed for pipeline leakage monitoring. The system cancollect real-time acoustic signal, upload the data to the server through the wiredor wireless means and process and analyze the data to locate the leak points. Theperformance test verifies the practicability and effectiveness of the system.