Fiber Optic Monitoring of Pipeline Subsidence: Analysis of Effective Sensor Cable Deployments

Long range, distributed fiber optic sensing systems have been an available tool for more than a decade to monitor pipeline subsidence integrity challenges. Effective deployment scenarios are an important decision to be factored into the selection of this monitoring equipment and typologies relative to specific project needs. In an effort to analyze the effectiveness of various fiber optic deployment conditions, a controlled field experiment was conducted. Within this field experiment, a variety of distributed fiber optic sensors and point sensors were deployed in predefined positions. These positions relative to the pipeline were selected to support a range of deployment needs including new construction or retrofitting of existing pipelines. A 16-inch diameter by 60-meter long epoxy coated pipeline that was capable of being pressurized to mimic operating conditions was utilized. This test pipe was installed in a typical trench setting. Conventional point gauges were installed at key locations on the pipeline. Fiber optic sensor cables were installed at key locations providing 14 alternative scenarios in terms of sensitivity, accuracy, and cost. After construction of the test pipeline, real time continuous monitoring via the array of conventional and fiber optic sensors commenced. A deep trench was excavated adjacent and parallel to the central portion of the pipeline which began to induce subsidence in the test pipeline. Continued monitoring of the various sensors produced real time visualization of the evolving subsidence. A comparison of the reaction of the sensors is compiled to provide an intelligent selection criteria for integrity managers in terms of accuracy, deployment, and costs for pipeline subsidence monitoring projects. In addition, further analysis of this sensor data should provide more insight into pipeline/soil interaction models and behaviors.

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Low-cost real-time fiber optic sensor for intrusion detection

Sensor Review ◽

10.1108/sr-03-2021-0090 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Adel Abdallah ◽

Mohamed M. Fouad ◽

Hesham N. Ahmed

Keyword(s):

Signal Processing ◽

Intrusion Detection ◽

Real Time ◽

Fiber Optic ◽

Reference Signal ◽

Fiber Optic Sensors ◽

Fiber Optic Sensor ◽

Content Type ◽

Intensity Modulated ◽

Optic Sensor

Purpose The purpose of this paper is to introduce a novel intensity-modulated fiber optic sensor for real-time intrusion detection using a fiber-optic microbend sensor and an optical time-domain reflectometer (OTDR). Design/methodology/approach The proposed system is tested using different scenarios using person/car as intruders. Experiments are conducted in the lab and in the field. In the beginning, the OTDR trace is obtained and recorded as a reference signal without intrusion events. The second step is to capture the OTDR trace with intrusion events in one or multiple sectors. This measured signal is then compared to the reference signal and processed by matrix laboratory to determine the intruded sector. Information of the intrusion is displayed on an interactive screen implemented by Visual basic. The deformer is designed and implemented using SOLIDWORKS three-dimensional computer aided design Software. Findings The system is tested for intrusions by performing two experiments. The first experiment is performed for both persons (>50 kg) in the lab and cars in an open field with a car moving at 60 km/h using two optical fiber sectors of lengths 200 and 500 m. For test purposes, the deformer length used in the experiment is 2 m. The used signal processing technique in the first experiment has some limitations and its accuracy is 70% after measuring and recording 100 observations. To overcome these limitations, a second experiment with another technique of signal processing is performed. Research limitations/implications The system can perfectly display consecutive intrusions of the sectors, but in case of simultaneous intrusions of different sectors, which is difficult to take place in real situations, there will be the ambiguity of the number of intruders and the intruded sector. This will be addressed in future work. Suitable and stable laser power is required to get a suitable level of backscattered power. Optimization of the deformer is required to enhance the sensitivity and reliability of the sensor. Practical implications The proposed work enables us to benefit from the ease of implementation and the reduced cost of the intensity-modulated fiber optic sensors because it overcomes the constraints that prevent using the intensity-modulated fiber optic sensors for intrusion detection. Originality/value The proposed system is the first time long-range intensity-modulated fiber optic sensor for intrusion detection.

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Sensing, Actuation, and Control of the SmartX Prototype Morphing Wing in the Wind Tunnel

Actuators ◽

10.3390/act10060107 ◽

2021 ◽

Vol 10 (6) ◽

pp. 107

Author(s):

Nakash Nazeer ◽

Xuerui Wang ◽

Roger M. Groves

Keyword(s):

Wind Tunnel ◽

Optical Fibers ◽

Fiber Optic ◽

Experimental Testing ◽

Single Mode ◽

Fiber Optic Sensor ◽

Sensor Data ◽

Random Errors ◽

Morphing Wing ◽

Actuator Dynamics

This paper presents a study on trailing edge deflection estimation for the SmartX camber morphing wing demonstrator. This demonstrator integrates the technologies of smart sensing, smart actuation and smart controls using a six module distributed morphing concept. The morphing sequence is brought about by two actuators present at both ends of each of the morphing modules. The deflection estimation is carried out by interrogating optical fibers that are bonded on to the wing’s inner surface. A novel application is demonstrated using this method that utilizes the least amount of sensors for load monitoring purposes. The fiber optic sensor data is used to measure the deflections of the modules in the wind tunnel using a multi-modal fiber optic sensing approach and is compared to the deflections estimated by the actuators. Each module is probed by single-mode optical fibers that contain just four grating sensors and consider both bending and torsional deformations. The fiber optic method in this work combines the principles of hybrid interferometry and FBG spectral sensing. The analysis involves an initial calibration procedure outside the wind tunnel followed by experimental testing in the wind tunnel. This method is shown to experimentally achieve an accuracy of 2.8 mm deflection with an error of 9%. The error sources, including actuator dynamics, random errors, and nonlinear mechanical backlash, are identified and discussed.

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Automated Detection and Quantification of Gas Influx Velocity in Wellbore from Fiber-Optic Sensor Data

10.1364/ais.2021.jth6a.11 ◽

2021 ◽

Author(s):

Gerald K. Ekechukwu ◽

Jyotsna Sharma

Keyword(s):

Fiber Optic ◽

Automated Detection ◽

Fiber Optic Sensor ◽

Sensor Data ◽

Optic Sensor ◽

Detection And Quantification

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Advanced distributed fiber optic sensors for monitoring real-time cementing operations and long term zonal isolation

Journal of Petroleum Science and Engineering ◽

10.1016/j.petrol.2017.08.072 ◽

2017 ◽

Vol 158 ◽

pp. 479-493 ◽

Cited By ~ 11

Author(s):

Qian Wu ◽

Sriramya Nair ◽

Michelle Shuck ◽

Eric van Oort ◽

Artur Guzik ◽

...

Keyword(s):

Real Time ◽

Fiber Optic ◽

Fiber Optic Sensors ◽

Zonal Isolation

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Automated Fiber-Optic System for Monitoring the Stability of the Pit Quarry Mass and Dumps

Occupational Safety in Industry ◽

10.24000/0409-2961-2021-4-19-26 ◽

2021 ◽

pp. 19-26

Author(s):

А.D. Меkhtiyev ◽

◽

E.G. Neshina ◽

P.Sh. Madi ◽

D.A. Gorokhov ◽

...

Keyword(s):

Rock Mass ◽

Optical Fiber ◽

Optical Fibers ◽

Fiber Optic ◽

Light Wave ◽

Single Mode ◽

Fiber Optic Sensors ◽

Fiber Optic Sensor ◽

Laboratory Sample ◽

Single Mode Optical Fiber

This article ls with the issues related to the development of a system for monitoring the deformation and displacement of the rock mass leading to the collapse of the quarry sides. Monitoring system uses point-to-point fiber-optic sensors. Fiber-optic sensors and control cables of the communication line are made based on the single mode optical fibers, which allows to measure with high accuracy the deformations and displacements of the rock mass at a distance of 30-50 km. To create fiber-optic pressure sensors, an optical fiber of the ITU-T G. 652.D standard is used. Laboratory sample is developed concerning the point fiber-optic sensor made based on the two-arm Mach-Zender interferometer using a single mode optical fiber for monitoring strain (displacements) with a change in the sensitivity and a reduced influence of temperature interference leading to zero drift. The article presents a mathematical apparatus for calculating the intensity of radiation of a light wave passing through an optical fiber with and without mechanical stress. A laboratory sample of single mode optical fibers based on the Mach-Zender interferometer showed a fairly high linearity and accuracy in the measurement and can be used to control the strain of the mass after appropriate refinement of its design. Mathematical expressions are also given for determining the intensity of the light wave when the distance between the fixing points of a single mode optical fiber changes depending on the change in the external temperature. A diagram for measuring strain using a point fiber-optic strain sensor is developed. Hardware and software package is developed, which can be used to perform a number of settings of measuring channels. The work is aimed at solving the production problems of the Kenzhem quarry of AK Altynalmas JSC.

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