Pipeline Leakage Monitoring Research Based On Fiber Bragg Grating Sensing Technology

The first chapter is introduction, in this part,first of all it is necessary to summarize the development of the pipeline transportation in our country since it was founded; review petroleum pipeline leakage caused by catastrophic accidents at home and abroad; put forward the importance of the pipeline security monitoring operation. Secondly expound the research of pipeline leakage and corrosion detection both at home and abroad, mainly present the development of optical fiber sensor in pipeline monitoring research; summarize the problems existing in pipeline inspection technology in the current years. At last, the sensing principle of fiber Bragg grating sensor are introduced,and then puts forward the research direction and research content.In the second chapter, this paper firstly present the theory of pipeline health monitoring based on pipeline hoop strain measurement; then deduce pipeline hoop strain measurement principle based on fiber bragg grating strain sensor. In order to verify the feasibility of this pipeline health monitoring theory which based on pipeline hoop strain measurement, we design the gas pipeline leakage monitoring experiment which apply small fiber bragg grating strain sensor.Through the gas pipeline leaking monitoring experiment, the response of fiber bragg grating strain sensor is studied under the listed condition:condition of branch pipeline leakage,condition of impact loads on the pipeline,condition of different leakage flow rate. Through this leakage monitoring experiment, it can be known that the method which based on measuring pipeline hoop strain is feasible.The main content of the second chapter is research and make the Fiber Bragg rating strain hoop sensor. The increase and decrease principle of the fiber Bragg grating strain sensor sensitivity and the sensor’s design principle are introduced firstly. According to characteristics of the pipeline monitoring and the design principle of fiber Bragg grating strain sensor, the fiber bragg grating strain hoop sensor is developed. In order to effective measuring pipeline hoop strain,a prestressing system used to fixe fiber bragg grating strain hoop sensor is developed. Through the fiber bragg grating strain hoop sensor calibration and repeatability experiment can get that:the performance of the fiber bragg grating strain hoop sensor is good; the fiber bragg grating strain hoop sensor has a good repeated applicability,it can be applied to practical engineering. The prestressing system can effectively reduce the strain transfer loss, it can make the fiber Bragg grating strain hoop sensor measuring pipeline pipeline’s hoop strain effectively. At last, the pipeline leakage monitoring experiment which apply fiber bragg grating strain hoop sensor is introduced. The main research purpose of this experiment is to study whether the fiber bragg grating strain hoop sensor can measure the leakage timely and accurately. Experiment demonstrate that this fiber Bragg grating strain hoop sensor is able to detect pipeline leakage accurately and timely, it has the value of practical application.