scholarly journals Post-Installed Fiber Optic Pressure Sensors on Subsea Production Risers for Severe Slugging Control

2015 ◽  
Author(s):  
Ammon N. Eaton ◽  
Seyed Mostafa Safdarnejad ◽  
John D. Hedengren ◽  
Kristie Moffat ◽  
Casey B. Hubbell ◽  
...  
Keyword(s):  
Fiber Optic ◽  
Flow Instability ◽  
Pressure Sensors ◽  
Offshore Structures ◽  
Fiber Optic Sensors ◽  
Mooring Lines ◽  
Two Phase ◽  
Pressure Sensing ◽  
Fbg Sensor ◽  
Control Schemes

Fiber optic sensors have gained increasing use in monitoring offshore structures. The sensors have successfully monitored flowlines, umbilicals, wells, Tension Leg Platform (TLP) tendons, production and drilling risers, and mooring lines. Fiber optic sensors are capable of monitoring strain, temperature, pressure, and vibration. While the success of fiber optic monitoring has been clearly demonstrated, the sensors are now under consideration for automation applications. This paper details the plausibility of using pressure measurements from post-installed fiber Bragg grating (FBG) sensors with Model Predictive Control (MPC) to suppress severe slugging in subsea risers. Prior control schemes demonstrate that slugging is mitigated using a topside choke valve. The most effective methods use a pressure measurement immediately upstream of the touchdown zone of the riser; however, the majority of production risers do not have pressure sensing at that location. With advances in subsea clamp design and bonding it is now possible to install a non-penetrating FBG sensor to monitor pressure near the touchdown zone without shutting down production. Stabilizing the two phase flow both reduces vibration-induced fatigue and has the potential to allow increased throughput with relaxed topside processing constraints. MPC predicts and adjusts for disturbances to avoid pressure and flow instability. The performance of the controller is influenced by sensor location, choke valve response time, and riser geometry. This study demonstrates that severe riser slugging is effectively controlled with MPC and a post-installed, non-penetrating FBG sensor.

scholarly journals Manufacturing of Microfluidic Devices with Interchangeable Commercial Fiber Optic Sensors

Sensors ◽  
2021 ◽  
Vol 21 (22) ◽  
pp. 7493
Author(s):  
Krystian L. Wlodarczyk ◽  
William N. MacPherson ◽  
Duncan P. Hand ◽  
M. Mercedes Maroto-Valer
Keyword(s):  
Porous Structure ◽  
Steady Flow ◽  
Microfluidic Device ◽  
Fiber Optic ◽  
Dynamic Pressure ◽  
Pressure Sensors ◽  
Microfluidic Devices ◽  
Fiber Optic Sensors ◽  
Valuable Insight ◽  
Local Pressure

In situ measurements are highly desirable in many microfluidic applications because they enable real-time, local monitoring of physical and chemical parameters, providing valuable insight into microscopic events and processes that occur in microfluidic devices. Unfortunately, the manufacturing of microfluidic devices with integrated sensors can be time-consuming, expensive, and “know-how” demanding. In this article, we describe an easy-to-implement method developed to integrate various “off-the-shelf” fiber optic sensors within microfluidic devices. To demonstrate this, we used commercial pH and pressure sensors (“pH SensorPlugs” and “FOP-MIV”, respectively), which were “reversibly” attached to a glass microfluidic device using custom 3D-printed connectors. The microfluidic device, which serves here as a demonstrator, incorporates a uniform porous structure and was manufactured using a picosecond pulsed laser. The sensors were attached to the inlet and outlet channels of the microfluidic pattern to perform simple experiments, the aim of which was to evaluate the performance of both the connectors and the sensors in a practical microfluidic environment. The bespoke connectors ensured robust and watertight connection, allowing the sensors to be safely disconnected if necessary, without damaging the microfluidic device. The pH SensorPlugs were tested with a pH 7.01 buffer solution. They measured the correct pH values with an accuracy of ±0.05 pH once sufficient contact between the injected fluid and the measuring element (optode) was established. In turn, the FOP-MIV sensors were used to measure local pressure in the inlet and outlet channels during injection and the steady flow of deionized water at different rates. These sensors were calibrated up to 140 mbar and provided pressure measurements with an uncertainty that was less than ±1.5 mbar. Readouts at a rate of 4 Hz allowed us to observe dynamic pressure changes in the device during the displacement of air by water. In the case of steady flow of water, the pressure difference between the two measuring points increased linearly with increasing flow rate, complying with Darcy’s law for incompressible fluids. These data can be used to determine the permeability of the porous structure within the device.

Active Flow Instability Control for Transient Two-Phase Electronics Cooling

2010 ◽  
Author(s):  
Tie Jun Zhang ◽  
Yoav Peles ◽  
John T. Wen ◽  
Michael K. Jensen
Keyword(s):  
Active Control ◽  
Flow Instability ◽  
Cooling System ◽  
Flow Instabilities ◽  
Future Research ◽  
Two Phase ◽  
Control Schemes ◽  
Boiling Flow ◽  
Flow Oscillations ◽  
Two Phase Cooling

Because of increasing power densities, refrigeration systems are being explored for two-phase cooling of ultra high power electronic components. Flow instabilities are potential problems in any two-phase refrigeration cooling system especially in transient applications. Oscillatory two-phase flow in a boiling channel can trigger transition to the critical heat flux (CHF). Active control methods can help better dynamic thermal management of electronic systems, even though transient two-phase boiling flow mechanisms are complicated. This paper presents a framework for the transient analysis and active control of pressure-drop flow instabilities under varying imposed heat loads. The first part of the paper is to study the external effects on boiling flow characteristics and the boiling oscillatory flow responses to transient heat load changes. Then based on the theoretical analysis of boiling flow oscillations, a set of active control schemes are developed and studied to suppress flow oscillations and, therefore, to increase the CHF. With the available control devices (i.e., inlet valve and supply pump), different active control schemes are studied to improve the transient two-phase cooling performance. Finally, a discussion is included to address potential future research.

Use of Fiber-Optic Information To Detect and Investigate the Gas-in-Riser Phenomenon

2021 ◽  
pp. 1-18
Author(s):  
Otto L. A. Santos ◽  
Wesley C. Williams ◽  
Jyotsna Sharma ◽  
Mauricio A. Almeida ◽  
Mahendra K. Kunju ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Fiber Optic ◽  
Research Effort ◽  
Pressure Sensors ◽  
Full Scale ◽  
Petroleum Engineering ◽  
Gas Migration ◽  
Two Phase ◽  
Engineering Research ◽  
Experimental Runs

Summary A potential application of optical fiber technologies in the well control domain is to detect the presence of gas and to unfold the gas dynamics inside marine risers (gas-in-riser). Detecting and monitoring gas-in-riser has become more relevant now when considering the application of managed pressure drilling operations in deep and ultradeep waters that may allow for a controlled amount of gas inside the riser. This application of distributed fiber-optic sensing (DFOS) is currently being evaluated at Louisiana State University (LSU) as part of a gas-in-riser research project granted by the National Academies of Sciences, the Gulf Research Program (GRP). Thus, the main objective of this paper is to present and discuss the use of DFOS and downhole pressure sensors to detect and track the gas position inside a full-scale test well during experimental runs conducted at LSU. The other objectives of this work are to show experimental findings of gas migration in the closed test well and to present the adequacy of a mathematical model experimentally validated to match the data obtained in the experimental trials. As a part of this research effort, an existing test well at the LSU Petroleum Engineering Research and Technology Transfer Laboratory (PERTT Lab) was recompleted and instrumented with fiber-optic sensors to continuously collect data along the wellbore and with four pressure and temperature downhole gauges to record those parameters at four discrete depths. A 2⅞-in. tubing string, with its lower end at a depth of 5,026 ft, and a chemical line to inject nitrogen at the bottom of the hole were also installed in the well. Seven experimental runs were performed in this full-scale apparatus using fresh water and nitrogen to calibrate the installed pieces of equipment, to train the crew of researchers to run the tests, to check experimental repeatability, and to obtain experimental results under very controlled conditions because water and nitrogen have well-defined and constant properties. In five runs, the injected gas was circulated out of the well, whereas in two others, the gas was left inside the closed test well to migrate without circulation. This paper presents and discusses the results of four selected runs. The experimental runs showed that fiber-optic information can be used to detect and track the gas position and consequently its velocity inside the marine riser. The fiber-optic data presented a very good agreement with those measured by the four downhole pressure gauges, particularly the gas velocity. The gas migration experiments produced very interesting results. With respect to the mathematical model based on the unsteady-state flow of a two-phase mixture, the simulated results produced a remarkable agreement with the fiber-optic, surface acquisition system and the downhole pressure sensors data gathered from the experimental runs.

Nursing Movement Monitoring System Utilizing Hetero-core Fiber Optic Sensors Embedded in Medical Thin Films

2018 ◽  
Vol 138 (12) ◽  
pp. 525-532
Author(s):  
Masahiko Ito ◽  
Yuya Koyama ◽  
Michiko Nishiyama ◽  
Emi Yanagisawa ◽  
Mariko Hayashi ◽  
...  
Keyword(s):  
Thin Films ◽  
Monitoring System ◽  
Fiber Optic ◽  
Fiber Optic Sensors ◽  
Core Fiber ◽  
Movement Monitoring

Embedded Fiber Optic Sensors for Integral Armor

2000 ◽  
Author(s):  
Bruce K. Fink ◽  
Kelli Corona-Bittick
Keyword(s):  
Fiber Optic ◽  
Fiber Optic Sensors

Erratum to “Angle-Resolved Characterization and Ray-Optics Modeling of Fiber-Optic Sensors”

2021 ◽  
Vol 39 (1) ◽  
pp. 336-336
Author(s):  
George. Y. Chen ◽  
Christophe A. Codemard ◽  
Philip M. Gorman ◽  
Jaclyn S. Chan ◽  
Michalis N. Zervas
Keyword(s):  
Fiber Optic ◽  
Fiber Optic Sensors ◽  
Ray Optics
Sign in / Sign up

Export Citation Format

Share Document