Characterization of Thermal and Acoustic Profiles of Potential Underwater Pipeline Leaks

2014 ◽  
Author(s):  
Shane Siebenaler ◽  
Eric Tervo ◽  
Mohan Kulkarni ◽  
Sandeep Patni ◽  
Glenn Gesoff
Keyword(s):  
Near Field ◽  
Thermal Response ◽  
Third Party ◽  
Analytical Models ◽  
Distributed Temperature Sensing ◽  
Offshore Installations ◽  
Underwater Pipeline ◽  
Optic Systems ◽  
Measurement Mechanism ◽  
Gas Leaks

Reliable detection of small potential leaks is a topic of significant interest for remote offshore pipelines. Potential leak cases of interest are pinhole leaks out of the bottom of the pipe due to corrosion, weld or seam cracks, or damage due to third-party contact. There are several emerging technologies that may have the potential to provide a means of detecting such leaks over long segments of underwater pipe. These technologies include distributed acoustic and distributed temperature sensing. A key element of evaluating the applicability of these systems is to characterize the behavior of leaks. It is critically important to understand how leaks behave when employing a technology that has only been previously used for other conditions. A joint-industry program was initiated to evaluate the thermal and acoustic behavior of hypothetical underwater leaks. The environments studied range from shallow, Arctic applications to deep offshore installations. Analytical models were assessed to predict the jetting behavior of simulated leaks and their near-field thermal response. This analysis was performed for both liquid and gas media. These models were validated by means of laboratory experiments. Acoustic characteristics of hypothetical liquid and gas leaks were determined by means of testing with hydrophones. This information can be leveraged by a number of technologies as the data are independent of the measurement mechanism. While the motivation of this work is to evaluate distributed fiber-optic systems, the data on leak characteristics may also provide indications on applicability of other techniques for detecting potential underwater leaks. The data from this project will allow the industry to improve the understanding of potential leaks from underwater pipelines and, hence, lay the foundation for determining appropriate detection systems.

scholarly journals Distributed Temperature Sensing Monitoring of Well Completion Processes in a CO2 Geological Storage Demonstration Site

Sensors ◽  
2018 ◽  
Vol 18 (12) ◽  
pp. 4239 ◽  
Author(s):  
Dasom Lee ◽  
Kwon Park ◽  
Changhyun Lee ◽  
Sang-Jin Choi
Keyword(s):  
Conventional Method ◽  
Exothermic Reaction ◽  
Thermal Response ◽  
Temperature Sensing ◽  
Temperature Calibration ◽  
Distributed Temperature Sensing ◽  
Cement Slurry ◽  
Well Completion ◽  
Calibration Methods ◽  
Gravel Packing

The Distributed Temperature Sensing (DTS) profiles obtained during well completion of a CO2 monitoring well were analyzed to characterize each well completion process in terms of temperature anomalies. Before analysis, we corrected the depth by redistributing the discrepancy, and then explored three temperature calibration methods. Consequently, we confirmed the depth discrepancy could be well corrected with conventional error redistribution techniques. Among three temperature calibration methods, the conventional method shows the best results. However, pointwise methods using heat coil or in-well divers also showed reliable accuracy, which allows them to be alternatives when the conventional method is not affordable. The DTS data revealed that each well completion processes can be characterized by their own distinctive temperature anomaly patterns. During gravel packing, the sand progression was monitorable with clear step-like temperature change due to the thermal bridge effect of sand. The DTS data during the cementing operation, also, clearly showed the progression up of the cement slurry and the exothermic reaction associated with curing of cement. During gas lift operations, we could observe the effect of casing transition as well as typical highly oscillating thermal response to gas lifting.

scholarly journals IDA-Pay: a secure and efficient micro-payment system based on Peer-to-Peer NFC technology for Android mobile devices

2012 ◽  
Vol 8 (4) ◽  
pp. 117 ◽  
Author(s):  
Luca Mainetti ◽  
Luigi Patrono ◽  
Roberto Vergallo
Keyword(s):  
Mobile Devices ◽  
Near Field ◽  
Operating Mode ◽  
Peer To Peer ◽  
Payment System ◽  
Third Party ◽  
Payment Systems ◽  
Shopping Experience ◽  
And Performance ◽  
System Effectiveness

The evolution of modern mobile devices towards novel Radio Frequency (RF) capabilities, such as Near Field Communication, leads to a potential for delivering innovative mobile services, which is still partially unexplored. Mobile proximity payment systems are going to enhance the daily shopping experience, but the access to payment security resources of a mobile device (e.g. the “Secure Element”) by third party applications is still blocked by smartphone and Operating System manufacturers. In this paper, the IDA-Pay system is presented, an innovative and secure NFC micro-payment system based on Peer-to-Peer NFC operating mode for Android mobile phones. It allows to deliver mobile-to-POS micro-payment services, bypassing the need for special hardware. A validation scenario and a system evaluation are also reported to demonstrate the system effectiveness and performance.

Hydraulic Fracturing Diagnostics Utilizing Near and Far-Field Distributed Acoustic Sensing DAS Data Correspondences

2021 ◽  
Author(s):  
Yinghui Wu ◽  
Robert Hull ◽  
Andrew Tucker ◽  
Craig Rice ◽  
Peter Richter ◽  
...  
Keyword(s):  
Hydraulic Fracture ◽  
Near Field ◽  
Fracture Propagation ◽  
Cost Effective ◽  
Hydraulic Fractures ◽  
Far Field ◽  
Distributed Temperature Sensing ◽  
Acoustic Sensing ◽  
Distributed Acoustic Sensing ◽  
Multiple Fibers

Abstract Distributed fiber-optic sensing (DFOS) has been utilized in unconventional reservoirs for hydraulic fracture efficiency diagnostics for many years. Downhole fiber cables can be permanently installed external to the casing to monitor and measure the uniformity and efficiency of individual clusters and stages during the completion in the near-field wellbore environment. Ideally, a second fiber or multiple fibers can be deployed in offset well(s) to monitor and characterize fracture geometries recorded by fracture-driven interactions or frac-hits in the far-field. Fracture opening and closing, stress shadow creation and relaxation, along with stage isolation can be clearly identified. Most importantly, fracture propagation from the near to far-field can be better understood and correlated. With our current technology, we can deploy cost effective retrievable fibers to record these far-field data. Our objective here is to highlight key data that can be gathered with multiple fibers in a carefully planned well-spacing study and to evaluate and understand the correspondence between far-field and near-field Distributed Acoustic Sensing (DAS) data. In this paper, we present a case study of three adjacent horizontal wells equipped with fiber in the Permian basin. We can correlate the near-field fluid allocation across a stage down to the cluster level to far-field fracture driven interactions (FDIs) with their frac-hit strain intensity. With multiple fibers we can evaluate fracture geometry, the propagation of the hydraulic fractures, changes in the deformation related to completion designs, fracture complexity characterization and then integrate the results with other data to better understand the geomechanical processes between wells. Novel frac-hit corridor (FHC) is introduced to evaluate stage isolation, azimuth, and frac-hit intensity (FHI), which is measured in far-field. Frac design can be evaluated with the correlation from near-field allocation to far-field FHC and FHI. By analyzing multiple treatment and monitor wells, the correspondence can be further calibrated and examined. We observe the far-field FHC and FHI are directly related to the activities of near-field clusters and stages. A leaking plug may directly result in FHC overlapping, gaps and variations in FHI, which also can be correlated to cluster uniformity. A near-far field correspondence can be established to evaluate FHC and FHI behaviors. By utilizing various completion designs and related measurements (e.g. Distributed Temperature Sensing (DTS), gauges, microseismic etc.), optimization can be performed to change the frac design based on far-field and near-field DFOS data based on the Decision Tree Method (DTM). In summary, hydraulic fracture propagation can be better characterized, measured, and understood by deploying multiple fibers across a lease. The correspondence between the far-field measured FHC and FHI can be utilized for completion evaluation and diagnostics. As the observed strain is directly measured, completion engineering and geoscience teams can confidently optimize their understanding of the fracture designs in real-time.

Improved Analytical Models for Single- and Multi-layer Silver Superlenses

2009 ◽  
Vol 1182 ◽  
Author(s):  
Ciaran P Moore ◽  
Richard John Blaikie ◽  
Matthew D Arnold
Keyword(s):  
Transfer Functions ◽  
Near Field ◽  
Single Layer ◽  
Analytical Models ◽  
Full Field ◽  
Accurate Performance ◽  
Imaging Performance ◽  
Performance Estimates ◽  
Continuous Metal ◽  
Good Agreement

AbstractSpatial-frequency transfer functions are regularly used to model the imaging performance of near-field �superlens� systems. However, these do not account for interactions between the object that is being imaged and the superlens itself. As the imaging in these systems is in the near field, such interactions are important to consider if accurate performance estimates are to be obtained. We present here a simple analytical modification that can be made to the transfer function to account for near-field interactions for objects consisting of small apertures in otherwise-continuous metal screens. The modified transfer functions are evaluated by comparison with full-field finite-element simulations for representative single-layer and multi-layer silver superlenses, and good agreement is found.

Thermodynamic Analysis of Thermal Responses in Horizontal Wellbores

2014 ◽  
Vol 137 (3) ◽  
Author(s):  
Luis F. Ayala H. ◽  
Ting Dong
Keyword(s):  
Steady State ◽  
Thermodynamic Analysis ◽  
Analytical Models ◽  
Distributed Temperature Sensing ◽  
Enthalpy Changes ◽  
Steady State Temperature ◽  
Horizontal Wellbore ◽  
Horizontal Wellbores ◽  
Physical Changes ◽  
Temperature Responses

Wellbore models are required for integrated reservoir management studies as well as optimization of production operations. Distributed temperature sensing (DTS) is a smart well technology deployed for permanent downhole monitoring. It measures temperature via fiber optic sensors installed along horizontal wellbores. Correct interpretation of DTS surveys has thus become of utmost importance and analytical models for analysis of temperature distribution behavior are critical. In this study, we first show how thermodynamic analysis can describe in detail the physical changes in terms of pressure and temperature behavior from the simplest cases of “leaky tank” to the horizontal wellbore itself. Subsequently, rigorous single-phase thermodynamic models for energy, entropy, and enthalpy changes in horizontal wellbores are derived starting from 1D conservative mass, momentum, and energy balance equations and a generalized thermal models, along with their steady-state temperature profile subsets, are presented. Steady-state applications are presented and discussed. The analysis presents the factors controlling horizontal wellbore steady-state temperature responses and demonstrates that wellbore thermal responses are neither isentropic nor isenthalpic and that the isentropic expansion-driven models and Joule–Thompson-coefficient (JTC) driven may be used interchangeably to analysis horizontal wellbore thermal responses.

Characterizing flat-top laser beams using standard beam parameters

2006 ◽  
Vol 84 (3) ◽  
pp. 223-240 ◽  
Author(s):  
S Saghafi ◽  
M J Withford ◽  
Z Ghoranneviss
Keyword(s):  
Near Field ◽  
Analytical Models ◽  
Model Parameters ◽  
Fourth Moment ◽  
Output Beam ◽  
Field Versus ◽  
Kurtosis Parameter ◽  
Beam Characteristic ◽  
Padé Method ◽  
Beam Parameters

We examine the correspondence between various models describing flat-top laser beam profiles using two standard parameters; namely, the M2 factor and the kurtosis parameter. Numerical expressions for M2, based on the second moment of the beam irradiance distribution in the near and far fields and for the kurtosis parameter, k, based on the fourth moment at the near field, are obtained. Plots of k in the near field versus M2 demonstrate the similarities between the different analytical models used to describe flat-top profiles. Using the Padé approximation, a relationship between k and M2, a new reference formula, is derived that predicts the values of M2 to within less than a percent for these flattened beams. This method is then extended to define numerical expressions relating the beam parameters (i.e., M2 and k) and the parameters describing the beam characteristic in each analytical model (model parameters). The results obtained using the Padé method are used to describe the output beam profiles for a high power copper vapour laser fitted with an unstable resonator.PACS Nos.: 42.55.–f, 42.55.Lt, 42.60.–v

scholarly journals Analytical calculation of intrinsic shielding effectiveness for isotropic and anisotropic materials based on measured electrical parameters

2014 ◽  
Vol 12 ◽  
pp. 83-89 ◽  
Author(s):  
M. Kühn ◽  
W. John ◽  
R. Weigel
Keyword(s):  
Near Field ◽  
Analytical Calculation ◽  
Anisotropic Materials ◽  
Electrical Circuit ◽  
Analytical Models ◽  
Shielding Effectiveness ◽  
Electrical Parameters ◽  
Measurement Systems ◽  
Definition Of ◽  
Adequate Measurement

Abstract. This contribution contains the mechanisms for calculation of magnetic shielding effectiveness from material samples, based on measured electrical parameters. For this, measurement systems for the electrical conductivity of high and low conductive material samples with respect to the direction of current flow are presented and discussed. Also a definition of isotropic and anisotropic materials with electrical circuit diagrams is given. For prediction of shielding effectiveness for isotropic and anisotropic materials, several analytical models are presented. Also adaptions to gain a near field solution are part of this contribution. All analytical models will also be validated with an adequate measurement system.

Assessment of Gas Leak Detection Techniques in Natural Gas Infrastructure: A Review

2021 ◽  
Author(s):  
Dulu Appah ◽  
Victor Aimikhe ◽  
Wilfred Okologume
Keyword(s):  
Natural Gas ◽  
Value Chain ◽  
Economic Loss ◽  
Leak Detection ◽  
Analytical Models ◽  
Detection Techniques ◽  
Gas Leakage ◽  
Gas Leak ◽  
Operational Activities ◽  
Gas Leaks

Abstract The undetected gas leak, also referred to as fugitive gas emissions, are produced from natural gas infrastructure during operational activities. If not monitored, this undetected gas leakage can lead to undesirable economic loss of natural gas from installed infrastructures and are often accompanied by toxic air pollutants that typically pose safety and public health concerns. The efficient quantification of gas leaks from natural gas infrastructure value chain is still largely inadequate. Several studies have repeatedly opined that the actual rate of leaks from natural gas infrastructure is often higher than the documented estimates. The latter is largely dependent on assumptions that rely on inadequate data. This study reviewed most of the existing methods implemented to detect and quantify gas leaks in natural gas infrastructure by assessing the techniques based on the amount of leak detected compared to the amount of gas produced from such facilities. The study illustrates both the problem of methane leakage and the opportunities for instantaneous reduction from natural gas transmission facilities. Furthermore, this review provides a detailed account of the various analytical models and instrumentation-based research performed to identify and quantify gas leak detection. The study opined that the uncertainties associated with efficient quantification of natural gas leak rates demonstrate the need for innovative approaches or processes to identify and quantify leak rates from natural gas infrastructure.

EFFECT OF BIDIRECTIONAL EXCITATIONS ON SEISMIC RESPONSE OF RC BUILDINGS

2012 ◽  
Vol 06 (03) ◽  
pp. 1250019 ◽  
Author(s):  
AMAN M. MWAFY
Keyword(s):  
Seismic Response ◽  
Near Field ◽  
Active Faults ◽  
Shear Capacity ◽  
Performance Criteria ◽  
Analytical Models ◽  
Rc Buildings ◽  
Response Modification Factor ◽  
Diverse Range ◽  
Axial Forces

This paper investigates the effect of the horizontal and vertical components of ground motions (HGM and VGM, respectively) on the seismic response of Reinforced Concrete (RC) buildings designed to modern capacity design principles and located in the vicinity of active faults. Fiber-based analytical models are used to monitor the global and local response of twelve reference structures, including verifying the response modification factor and tracing the member shear supply-demand response using a ductility- and axial force-sensitive shear strength approach. The simulation models are subjected to near-field earthquake records with increasing severity up to collapse, including and excluding VGM. The results indicate that the lower the contribution of horizontal seismic forces to the seismic response, the higher is the significance of VGM. The fluctuation of axial forces in vertical structural members significantly increases when including VGM. This not only has direct consequences on tension and compression response but also has impact on shear capacity. The diverse range of buildings and performance criteria and large number of incremental dynamic analyses confirm the importance of including VGM in seismic design and assessment of contemporary RC buildings, and hence cast doubts on the reliability of pre-code structures located in the vicinity of active faults.

Horizontal-Steam-Injection-Flow Profiling Using Fiber Optics

SPE Journal ◽  
2019 ◽  
Vol 24 (02) ◽  
pp. 431-451 ◽  
Author(s):  
M.. Shirdel ◽  
R. S. Buell ◽  
M. J. Wells ◽  
C.. Muharam ◽  
J. C. Sims
Keyword(s):  
Fiber Optics ◽  
Fiber Optic ◽  
Steam Injection ◽  
Flow Profile ◽  
Distributed Temperature Sensing ◽  
Flow Loop ◽  
Conformance Control ◽  
Well Completion ◽  
Injection Flow ◽  
Optic Systems

Summary Steam-conformance control in horizontal injectors is important for efficient reservoir-heat management in heavy-oil fields. Suboptimal conformance and nonuniform heating of the reservoir can substantially affect the economics of the field development and oil-production response and result in nonuniform steam breakthrough. To achieve the required control, it is essential to have an appropriate well-completion architecture and robust surveillance. Five fiber-optic systems, each with a unique steam-conformance-control-completion configuration, have been installed in two horizontal steam injectors to help mature steam-injection-flow profiling and conformance-control solutions. These fiber-optic systems have used custom-designed fiber-optic bundles of multimode and single-mode fibers for distributed-temperature sensing (DTS) and distributed-acoustic sensing (DAS), respectively. Fiber-optic systems were also installed in a steam-injection-test-flow loop. All the optical fibers successfully acquired data in the wells and flow loop, measuring temperature and acoustic energy. A portfolio of algorithms and signal-processing techniques was developed to interpret the DTS and DAS data for quantitative steam-injection-flow profiling. The heavily instrumented flow-loop environment was used to characterize DTS and DAS response in a design-of-experiment (DOE) matrix to improve the flow-profiling algorithms. These algorithms are dependent on independent physical principles derived from multiphase flow, thermal hydraulic models, acoustic effects, large-data-array processing, and combinations of these methods for both transient and steady-state steam flow. A high-confidence flow profile is computed using the convergence of the algorithms. The flow-profiling-algorithm results were further validated using 11 short-offset injector observation wells wells in the reservoir that confirmed steam movement near the injectors.

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