An Optical Fiber Sensor for Oriented Bending Based on Eccentric UV Exposure

The optical fiber sensor for oriented bending based on eccentric UV exposure is fabricated. With the eccentric UV exposure on the ready-made Michelson interference fiber structure, the optical sensor gives the oriented bending characteristics by changing the radial circular symmetry of fiber cladding refractive indexes. The principle of the asymmetric process of the eccentric exposure to cladding mode are analyzed. The bending loss of the excited cladding mode in different radial directions is detected. The experimental results show that the Michelson interference has some oriented bending characteristics in the eccentric UV exposure process. There are different bending sensitivity in different radial directions. Furthermore, the bending sensitivity is higher on the exposed side and the curvature sensitivity is 5.5 dB·m. On the opposite side, the bending sensitivity is lower and the curvature sensitivity is -1.31 dB·m. With these oriented bending characteristics, the optical sensor can be applied to oil and gas exploration and development and to oriented seismic wave vector detection.

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Applied Research of Optical Fiber Sensor in Oil and Gas Pipe Corrosion Monitoring

Laser & Optoelectronics Progress ◽

10.3788/lop51.020604 ◽

2014 ◽

Vol 51 (2) ◽

pp. 020604 ◽

Cited By ~ 1

Author(s):

杨牧 Yang Mu ◽

刘秀红 Liu Xiuhong ◽

刘伟 Liu Wei ◽

李再春 Li Zaichun

Keyword(s):

Optical Fiber ◽

Applied Research ◽

Oil And Gas ◽

Optical Fiber Sensor ◽

Fiber Sensor ◽

Corrosion Monitoring

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Basic Strategy of Health Monitoring on Submarine Pipeline by Distributed Optical Fiber Sensor

Volume 2: Safety and Reliability; Pipeline Technology ◽

10.1115/omae2003-37048 ◽

2003 ◽

Author(s):

Wei-Liang Jin ◽

Jian-Wen Shao ◽

En-Yong Zhang

Keyword(s):

Optical Fiber ◽

Oil And Gas ◽

Optical Fiber Sensor ◽

Fiber Sensor ◽

Gas Transfer ◽

Pipeline System ◽

Submarine Pipeline ◽

Long Distance ◽

Distributed Optical Fiber Sensor ◽

Distributed Optical Fiber

Submarine pipeline system is a main pattern in collection and transmission of offshore oil and gas, which sends oil and gas from offshore oil/gas field to land, and it plays an important role in the production of oil and gas. Because of the complicated and harsh condition in which pipeline system works, such as impulsion, corrosion and free-spanning vibration, failure of submarine pipeline system occurs occasionally, it causes oil leakage, environment pollution and economic losses. Health monitoring is a feasible and effective manner to ensure submarine pipeline safe and reliable during service, especially when all factors affecting pipeline failure are not still entirely realized or controlled. The basic strategy of a new real-time monitoring system for long distance submarine pipeline is introduced in this paper, which has the function of diagnosis and auto-alarm. In this system, a new distributed optical fiber sensor (DOFS), which uses optical time domain reflectometry theory based on Brillouin backscatter, is applied to monitor the strain and temperature along the pipeline. To be used for long distance submarine pipeline, this system applies Wavelength Division Multiplex (WDM) technology and series DOFSs in series so as to extend the measure scope for long distance submarine pipeline. By using signal processing system to analyze the outcome data of sensor, the strain along the pipeline can be obtained. If the strain reaches the alarm setting, the system will send out caution and meanwhile accurately give the damage position. The system can also analyses vibration frequency of pipeline, if free-spanning vibration occurs, caution will also be given, so that the operator can take some measures in time to avoid the failure of pipeline. In this paper, the makeup of distributed optical fiber sensor and developing principle are specified, system development, application and construction in engineering are analyzed as well. The brand new practical system can not only be used for submarine oil and gas pipeline but also for land oil and gas transfer system, city coal gas transfer system, electricity-transmission cable and so on. This system can be widely used in many prospects of other industries.

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Optical Fiber Sensor Experimental Research Based on the Theory of Bending Loss Applied to Monitoring Differential Settlement at the Earth-Rock Junction

Journal of Sensors ◽

10.1155/2015/346807 ◽

2015 ◽

Vol 2015 ◽

pp. 1-13 ◽

Cited By ~ 1

Author(s):

Jianchun Qiu ◽

Dongjian Zheng ◽

Kai Zhu ◽

Bin Fang ◽

Lin Cheng

Keyword(s):

Optical Fiber ◽

Optical Fiber Sensor ◽

Single Mode ◽

Differential Settlement ◽

The Body ◽

Fiber Sensor ◽

Monitoring Device ◽

The Earth ◽

Bending Loss ◽

Sensor Monitoring

Considering the differential settlement in the junction between the structure perpendicular to the dike and the body and foundation of dike (called the earth-rock junction in this paper) during runtime, an experimental investigation of optical fiber sensor monitoring was conducted. Based on the sensing mechanism of single-mode optical fiber bending loss, the experiment focused on the influence of the bending radius of an optical fiber on the bending loss. In view of the characteristics of the differential settlement in the earth-rock junction, we designed a butterfly-type optical fiber sensor and composite optical fiber sensor for monitoring device in monitoring the differential settlement to enlarge the monitoring range and improve the sensibility of optical fiber sensor. Based on the research on the working principle and bending properties of the composite optical fiber monitoring device, we conducted experiments on the bending of the composite optical fiber sensor monitoring device and the use of the device for monitoring the differential settlement. These experiments verified the feasibility of the composite optical fiber sensor monitoring device at monitoring the differential settlement in the earth-rock junction.

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Displacement Sensing of an Active String Actuator by an Optical Fiber

Engineering Proceedings ◽

10.3390/ecsa-8-11310 ◽

2021 ◽

Vol 10 (1) ◽

pp. 35

Author(s):

Weihang Tian ◽

Shuichi Wakimoto ◽

Kazuya Nagaoka ◽

Yorifumi Yoshimoto ◽

Takefumi Kanda ◽

...

Keyword(s):

Optical Fiber ◽

Optical Fiber Sensor ◽

Fiber Sensor ◽

Radius Of Curvature ◽

Artificial Muscles ◽

Rigid Displacement ◽

Displacement Estimation ◽

Displacement Sensors ◽

Bending Loss ◽

Displacement Force

We have fabricated a string-shaped actuator called “Active string” that has high contractile displacement/force by accumulating thin pneumatic artificial muscles using the string production process. However, displacement control of the active string is challenging because general bulky and rigid displacement sensors are not suitable for the sensor element of the active string. Therefore, in this report, a flexible optical fiber sensor is combined with the active string to enable sensing of its displacement. As the active string contracts, the radius of curvature of the optical fiber decreases, and light intensity propagating in the optical fiber decreases due to bending loss. The experimental results showed that the optical fiber sensor value changed with corresponding to the displacement of the active string. It shows the possibility that it is possible to make a displacement estimation of the displacement of the active string using an optical fiber sensor.

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A Dual-Parameter Fusion Distributed Optical Fiber Sensor System for Oil and Gas Pipeline Monitoring

Journal of Applied Mathematics and Physics ◽

10.4236/jamp.2019.711200 ◽

2019 ◽

Vol 07 (11) ◽

pp. 2909-2916

Author(s):

Baoji Li ◽

Hongliang Wu ◽

Yangquan Xie ◽

Zhiyong Dai

Keyword(s):

Optical Fiber ◽

Oil And Gas ◽

Optical Fiber Sensor ◽

Gas Pipeline ◽

Sensor System ◽

Fiber Sensor ◽

Distributed Optical Fiber Sensor ◽

Pipeline Monitoring ◽

Distributed Optical Fiber

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Stress Analysis of a Resin Pocket Embedded in Laminated Composites for an Optical Fiber Sensor

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.419-420.293 ◽

2009 ◽

Vol 419-420 ◽

pp. 293-296 ◽

Cited By ~ 1

Author(s):

Shiuh Chuan Her ◽

Bo Ren Yao ◽

Shien Chin Lan ◽

Chun Yen Liu

Keyword(s):

Stress Concentration ◽

Optical Fiber ◽

Optical Sensors ◽

Optical Sensor ◽

Laminated Composites ◽

Optical Fiber Sensor ◽

High Stress ◽

Small Diameter ◽

Fiber Sensor ◽

Resin Pocket

Optical fiber sensors have a number of advantages over conventional electronic sensors such as light weight, small diameter and immunity to electromagnetic interference. Despite all the advantages of optical sensors, one must recognize that optical fibers are foreign entities to the host structure, therefore will induce stress concentration in the vicinity of the embedded sensor. As an optical sensor is embedded between plies, a lenticular resin pocket exists in the composite plies. The resin pocket acts as a crack-like region, and can form the site of the initiation of the delamination under mechanical loads. In this investigation, the geometry of the lenticular resin pocket around the optical sensor is derived basing on the principal of minimum potential energy. It shows that the geometry of the resin pocket is dependent on the stiffness of the plies, the stacking sequence, the diameter of the optical fiber and the curing pressure. The stress distributions in the resin pocket and in the laminated composites are obtained by using the finite element method. The numerical results demonstrate that the stress increases rapidly in the vicinity of the optical fiber sensor, causing a high stress concentration factor. The high stress field may produce delamination and fracture in the composite.

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