Research On Gas Pipeline Detection Technology Based On Fiber Sensor

Natural gas pipeline is the main transportation mode of natural gas.Optical fiber sensor has a broad application prospect in natural gas pipeline detection as an efficient detection method.The paper analyzes the temperature measurement principle of distributed optical fiber temperature measurement system,and studies the temperature measurement system consisting of laser light source,coupler,data acquisition card,test host and test fiber.The corresponding source wavelength and avalanche are determined according to the functions of each part.Parameters such as diode type,sampling frequency and sensing fiber type;when the gas pipeline leaks,the high pressure gas in the tube is quickly lost,causing the change of the ambient temperature near the leak point.The system realizes the monitoring of the ambient temperature around the gas pipeline.Detection of leaks.Through the investigation of the on-site experimental environment,multiple sets of comparative experiments were set according to the actual situation,and the distributed optical fiber temperature measurement system was used to record the temperature signals under various working conditions.For the temperature measurement signal during pipeline leakage,the methods such as cumulative averaging method,wavelet denoising method,empirical mode method and wavelet singular value analysis method are used to denoise the signal,improve the signal-to-noise ratio,and finally improve the system fault.The purpose of diagnostic accuracy.The analysis shows that the wavelet singular value analysis method is based on wavelet threshold denoising and the singular value decomposition and threshold reconstruction denoising effect is improved compared with wavelet denoising.The distributed optical fiber temperature measurement system is used to detect the temperature change of the pipeline leakage,thereby detecting the leakage of the gas pipeline.A variety of methods for the denoising of the temperature measurement signal,improve the detection accuracy of the system,can diagnose the fine leakage of the pipeline,and thus avoid accidents.