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- Information Technology > Knowledge Management (0.40)
- Information Technology > Communications > Collaboration (0.40)
Abstract The recent implementation of autonomous wireline and slickline conveyance and spooling in the North Sea represents the first offshore wireline autonomous operation and the first slickline autonomous operation. With more than 50 runs completed, it is now possible to establish a baseline of the performance of the automated system and compare the performance to that of manual job execution. Traditional wireline/slickline units implement limited automation capabilities. Even the more advanced models rely on basic control systems (such as programmable logic controllers) to provide features such as speed control or static tension limits. The wireline and slickline autonomous conveyance system represents a technological leap, introducing an automation server in the unit. This device runs advanced software applications to seamlessly conduct run-in-hole and pull-out-of-hole activities without human intervention. The system employs reasoning algorithms to determine the optimal and safe actions required to achieve a given goal, even in a changing environment. An advanced tension model enables dynamic tension limit updates to maintain safety throughout the job. During its 1 year in operations, the system has been extensively used in multiple wells and is now a standard operating practice. Data collected to compare the performance of manual and autonomous operations demonstrate the increased consistency of the automated system. The current work presents an analysis of the running speeds and tension limits. Experience has enabled identification of areas where autonomous operations bring the most value to the operator, as well as potential areas for improvement. Autonomous intervention is one of the digital transformation goals for many operators and service providers. This paper provides a strategy for its implementation, as well as an analysis of its performance and value based on the collected data.
Abstract In situations where visual stimuli are uncertain or degraded, auditory perception is crucial and can complement visual perception. Research on multimodal perception has confirmed in many areas of study that the existence of one stimulus can impact the perception of another type of stimulus. Based on these concepts, which are well-established in cognitive sciences, we introduce the idea of expanded (or augmented) imaging in geophysics, which refers to an integrated and coherent data representation based on dual-sensory (audiovisual) perception of the same data set. First, we explain the basic principles of multimodal analysis of seismic data using the theory of augmented imaging. Then, we provide examples and applications on real data at varying spatial scales, from individual seismic traces to entire seismic sections.
- Geophysics > Seismic Surveying > Seismic Processing (1.00)
- Geophysics > Seismic Surveying > Seismic Interpretation (0.93)
- Media > Music (1.00)
- Leisure & Entertainment (1.00)
- Health & Medicine (1.00)
- Energy > Oil & Gas > Upstream (1.00)
- Europe > Norway > Barents Sea > PL 532 > Block 7220/8 > Johan Castberg Field > Tubåen Formation (0.98)
- Europe > Norway > Barents Sea > PL 532 > Block 7220/8 > Johan Castberg Field > Stø Formation (0.98)
- Europe > Norway > Barents Sea > PL 532 > Block 7220/8 > Johan Castberg Field > Nordmela Formation (0.98)
- (9 more...)
ABSTRACT Underground storage cavern has been increasingly exploited as it has many advantages such as reducing investment, economizing land use and improving safety compared with storage above the ground surface. We employ the hydromechanical coupled FDEM to simulate the excavation and operation phases of the underground storage cavern with a water curtain system (WCS), taking into consideration the natural discrete fracture network (DFN). The simulation results captured the propagation and slipping of the pre-existing DFN during the excavation and operation process. We quantitatively evaluate the containment performance based on the water inflow and pore pressure distribution. This study provides new insights into evaluating the stability of cavern-surrounding rock masses and containment performance of underground storage caverns. INTRODUCTION Underground storage caverns have better performance on safety, security, economy, and greater environmental acceptance compared with traditional storage infrastructures such as storage tanks and pipelines. Several large underground storage caverns have been constructed, for example, Jurong rock caverns in Singapore (Zhou & Zhao, 2016) and Huangdao underground oil storage caverns in China (Wang et al., 2015). Underground storage caverns are constructed in fractured rock masses, confining the storage medium (such as oil and gas) by maintaining groundwater pressure around caverns which is also called hydraulic confinement (Aberg, 1978; Froise, 1987; Lindblom, 1997). The basic principle of underground containment the cavern is that no gas could leak as long as the water pressure increases along all possible gas leakage paths away from the cavern (Goodall et al., 1988). To enhance the sealing performance, water curtain systems (WCS) are constructed to manually control the pore pressure distribution by regulating the water curtain pressure. (Shi et al., 2018). Previous studies has evaluated the stability of excavated rock masses (Mohanty & Vandergrift, 2012; Ma et al., 2016; Zhuang et al., 2017) and containment performance (Xu et al., 2018; Liu et al., 2021) by using in-situ monitoring methods and numerical simulation. However, the fracture propagation and slip induced by the excavation and operation of the storage cavern, as well as the resultant fluid pressure variation, have not been illustrated.
- North America (0.69)
- Asia > China (0.50)
Summary Petroleum reserves assessment is a routine exercise performed by every oil and gas company. The reserves estimation could be achieved using deterministic or probabilistic methods. Depending on the type of data available, different assumptions and data are used at various stages of the assessment throughout the E&P life cycle (i.e., exploration, appraisal, development, depletion, and so on). The accuracy of the reserves estimate is highly dependent on the amount and quality of data available and experience of the evaluator. The estimates become more accurate and refined as more and more data become available. The objective of this paper is to urge the industry to rethink the terminology used for categorizing probabilistic reserves (P90, P50, and P10) using a single probability distribution. As a routine practice, we consider 1P = P90 = proved reserves, 2P = P50 = proved + probable reserves, and 3P = P10 = proved + probable + possible reserves. The reserves categories depend on the range of uncertainty as shown in the Petroleum Resources Classification Framework of the Petroleum Resources Management System (PRMS). It is shown here that P50 (or mean/expected value) of each reserve category is a more robust and logical value to be used for categorizing reserves. The P90 and P10 demonstrate confidence levels of a certain probability distribution, which is owing to the standard deviation (proxy for uncertainty) of the specific distribution and not the range of uncertainty. The range in uncertainty is assessed from varying standard deviations from more than one probability distribution. Therefore, the use of P90 and P10 for reserves categorization contradicts the x-axis title of the Petroleum Resources Classification Framework in the PRMS. The P90, P50, and P10 from a single probability distribution with a single standard deviation will have the same uncertainty (not range of uncertainty). The difference between P90 and P10 is also owing to this single standard deviation. Some examples are presented in this paper to show this and to show that P50 (or mean) with its corresponding standard deviation (indication of uncertainty) could be more appropriately used to book and categorize reserves. The concept of expected value (EV) is also revisited as this may not be correctly reported in some publications.
New Development in Pulsed Neutron Technologies to Enhance Faster Data Recovery and Reduce Operation Logging Time for Three-Phase Saturation Analysis
Nardiello, Roberto (Baker Hughes Nigeria) | Chace, David (Baker Hughes Nigeria) | McGlynn, Ian (Baker Hughes Nigeria) | Akagbosu, Pius (Baker Hughes Nigeria) | Ouadah, Salim (Baker Hughes Nigeria) | Ramaswamy, Vijay (Baker Hughes Nigeria) | Toumelin, Emmanuel (Chevron Nigeria Limited) | Oduwole, Ajibola (Chevron Nigeria Limited) | Ogofa, Matthew E. (Chevron Nigeria Limited) | Ekeng, Oyie Maureen (Chevron Nigeria Limited)
Abstract A new wireline pulsed neutron technology has recently been introduced in the offshore area of the Niger Delta to improve service and data quality with a faster speed and a simultaneous acquisition of multiple measurement modes, resulting in substantial reduction of rig and operational time. The scope of this application was to qualify this new technology and to demonstrate the capability to log up to three times faster than previous-generation tools with the same precision and accuracy, while providing simultaneous pulsed neutron capture (PNC) measurements for gas saturation, and inelastic carbon oxygen (C/O) ratio-based modes for oil saturation from the same logging pass. Two wells were logged with both existing and new technologies for comparison purposes in mature fields that have been in active production since the 1960's and which are still under development. A third well was logged with only the new tool after the benefits of the new technology were proven, but this paper will focus on the results from the wells in which both legacy and new tools were directly compared. The key features of the new instrument include: 1) three Lanthanum Bromide (LaBr3) detectors with high density, high count-rate and high-resolution characteristics, 2) an enhanced pulsed neutron source with higher output, 3) and digital electronics capable of processing the increased gamma ray count rate. The new instrument allows faster logging speed and time savings with the same precision as previous generation tools with either a single pass at legacy slower speeds, or logging in multiple passes at up to three times faster speeds. In addition, a new logging mode has been introduced that allows simultaneous acquisition of C/O and PNC (e.g. Sigma ∑ and gas indicators) ratiobased gas saturation measurements from three detectors for simultaneous 3-phase saturation determination. Nuclear modeling is used to predict various measurement responses over a wide range of borehole, casing, formation, and fluid conditions. The combination of these models with actual field measurements determines the fluid saturation profile with high accuracy. Results confirmed the same or higher saturation evaluation quality with 65 percent savings in logging time and 40-55 percent savings in total operation time. This paper presents field examples, and reports on results and data quality from this technical development.
- Europe (1.00)
- Africa > Nigeria (1.00)
- North America > United States > Texas (0.69)
Norwegian Released Wells Project: Study Design, Material Preparation, Measurements and Data Analysis
Kolbjørnsen, Odd (Lundin Energy / University of Oslo) | Hammer, Erik (Lundin Energy) | Pruno, Stefano (Stratum Reservoir) | Wellsbury, Peter (Rockwash Geodata) | Kusak, Malgorzata (The Norwegian Oil and Gas Association)
Abstract The Released Wells Initiative is a joint industry project administrated and organized by the Norwegian Oil and Gas Association and funded by the majority of companies operating on the Norwegian Continental Shelf (NCS). The project is unique on a worldwide scale, as it will analyze every drill cutting sample from every exploration and appraisal well in the Norwegian national archive. The archive contains about 700,000 samples of unwashed ditch cuttings from more than 1900 wells. Each sample is washed and dried according to a consistent automated procedure, and preserved both in a digital format, using high-resolution white light (WL) and UV (UV) photography and X Ray Fluorescence (XRF) analysis. The cleaned samples from all the wells are available for future analysis. The eighty most recently released wells were subjected to an extended suite of measurements: X-Ray Diffraction (XRD), automated mineralogy (QEMSCAN), Infrared spectroscopy (IRS) and total organic carbon measurement (TOC). We present details of the study design, sample preparation and analysis process. The extended set of observations are not selected based on the results of other measurements. The data set is therefore an independent source of information void of conditional dependencies between measurement types. We discuss the possibilities that the dataset offers and present results from analysis that have been made. In a set of repeated measurements, we find a high degree of consistency. The correlation between the two samples sets is found to be above 0.95 for XRF, XRD, QEMSCAN, IRS, and for the average photon count in white light images. For the UV images the correlation is lower, however typically these UV images have a low photon count. In a case example we show how the XRF data contribute to understanding the provenance of the Brent Group in a region of the North Sea. We show how the study design enables methods of advanced analytics, where the extended measurement set can be used to train predictive models. In our data analysis we utilize boosting threes to predict e.g., XRD mineralogy from XRF data. We report an out of sample error of 4.5%-6.9%, for quartz, total clay and carbonates. We further discuss opportunities and challenges with the dataset. The dataset provides opportunities to aid interpretation and future decision making, with impacts on drilling, completion, geological interpretation, modelling, production and future projects (including carbon capture and storage). The project is also unique in terms of openness as the complete data set will be released to the public in 2024.
- North America > United States (1.00)
- Europe > Norway > North Sea > Northern North Sea (0.46)
- Geology > Mineral > Silicate > Phyllosilicate (1.00)
- Geology > Geological Subdiscipline (1.00)
- Geology > Rock Type (0.94)
- Geophysics > Borehole Geophysics (0.95)
- Geophysics > Seismic Surveying (0.67)
- Energy > Oil & Gas > Upstream (1.00)
- Government > Regional Government > North America Government > United States Government (0.56)
- Europe > Norway > North Sea > Northern North Sea > East Shetland Basin > Tampen Area (0.99)
- Europe > United Kingdom > North Sea > Central North Sea > Ness Formation (0.93)
- Europe > Norway > North Sea > Tarbert Formation (0.93)
- (10 more...)
- Reservoir Description and Dynamics > Reservoir Characterization > Exploration, development, structural geology (1.00)
- Data Science & Engineering Analytics > Information Management and Systems > Data mining (1.00)
- Reservoir Description and Dynamics > Formation Evaluation & Management > Open hole/cased hole log analysis (0.95)
- Reservoir Description and Dynamics > Storage Reservoir Engineering > CO2 capture and sequestration (0.86)
- Information Technology > Artificial Intelligence > Machine Learning (1.00)
- Information Technology > Data Science > Data Mining > Big Data (0.48)
ABSTRACT Escorting merchant ships sometimes requires icebreakers to widen channels in ice-covered waters. To better understand the icebreaker's channel widening capability, this paper presents full-scale tests of the Icebreaker (IB) Polaris in the Bay of Bothnia during 2021 and analyses the relation between measured channel widths and icebreaker's operations, those being: combinations of advancing speeds and two stern azimuth thrusters’ toe-in angles. The tests showed that operating IB Polaris ahead at a low speed with toe-in angles could open a wide channel in level ice. Such an operation could also widen a previously opened own channel more. This paper also provides an approach to digitally measuring channel widths from drone videos. INTRODUCTION Safe and effective shipping in ice-covered waters requires a reliable winter navigation system. In the northern Baltic Sea area, the Finnish-Swedish winter navigation system governs maritime transportation in winter conditions, ensuring merchant vessels safely reach ports (Goerlandt et al., 2017). Icebreaker assistance as one component of the winter navigation system provides icebreaking service for merchant ships. Icebreakers can escort a merchant ship and lead a convoy by opening a channel for the assisted ships to travel in brash ice channel conditions. If the assisted merchant ship's beam is wider than the icebreaker's, the channel opened by the icebreaker may not be wide enough for the assisted ship. The surrounding level ice may result in significant resistance to the assisted ship, causing potential risks of collision with other following ships. Therefore, channel widening as an ice management option is required in such circumstances. An ice channel could be widened by one icebreaker or a double convoy. The double convoy means that two icebreakers open or widen a channel side by side or one after the other. Such operation may require relatively complex management by considering many factors, such as available icebreakers and operation costs. Such a wide channel could also be opened by one icebreaker. For example, icebreakers could utilize reamers to widen a channel by changing ballast conditions. However, implementing reamers on an icebreaker requires more structural design and building cost; additionally, the effect of reamers on channel widening may not be significant. Instead of adding reamers on the ship, actively using the azimuth propulsion system could be a more economical and flexible for safe and efficient operations in icy waters. By customizing the icebreaker's speed, azimuth thruster turning angles and propulsion power, the channel can be widened in a prevailing ice condition. For the reader's interest, solutions of opening channels other than using icebreakers do exist. Tugboat operated in freshwaters, such as Lake Saimaa (the largest freshwater lake in Finland) and the Saimaa Canal, can break freshwater ice during the winter season by connecting a detachable icebreaking bow (Aker Arctic, 2018).
Uncertainty Quantification of Motor Efficiency Map for All-Electric Ships
Guo, Fengxiang (Institute of Marine Power Plant and Automation, Shanghai Jiao Tong University, Shanghai / State Key Laboratory of Ocean Engineering, Shanghai Jiao Tong University, Shanghai) | Chen, Li (Institute of Marine Power Plant and Automation, Shanghai Jiao Tong University, Shanghai / State Key Laboratory of Ocean Engineering, Shanghai Jiao Tong University, Shanghai)
ABSTRACT The analysis of data acquired by the dynamometer bench indicates that motor efficiency at each operating point appears basically normal distribution. Consequently, Gaussian Process Regression (GPR) is employed to estimate the motor efficiency mean map and efficiency standard deviation map for quantifying efficiency uncertainty caused by factors such as temperature, control tracking error and measurement noise. The results show that maximum absolute error (MAE) between the efficiency mean maps established by GPR and the measured data does not exceed 0.2270%, and MAE between the predicted efficiency standard deviation and the actual value is below 0.0792. It demonstrates that GPR can be introduced to quantify efficiency uncertainty effectively when modeling motor efficiency map, which provides a reference for study on motor efficiency uncertainty. INTRODUCTION Electric ships are currently the most promising method to reduce the air pollution and tackle excessive fossil energy crisis (Inal et al., 2022). Accurately evaluating the energy consumption, battery capacity and emissions based on the ship dynamics model is essential for design purpose (Nuchturee et al., 2020). As the critical component in the drive configuration of all-electric ships, previous studies have reported that efficiency map is currently one of the main application forms of electrical machine when constructing energy consumption model for vessel and tug ship (Zhu et al., 2018; Zhu et al., 2019). However, the actual operating conditions of motor are complex and changeable, which is quite different from the calibration test for efficiency map, resulting in a notable gap between the actual motor efficiency and the efficiency from the map (Li et al., 2015). Additionally, factors such as ambient temperature, control tracking error, and long-term aging bring greater uncertainty to motor efficiency (Bucci et al., 2016; Kärkkäinen et al., 2019; Ostroverkhov and Buryk, 2019). Therefore, in design stage, only utilizing the calibrated motor efficiency map to set up ship energy consumption model would generate a considerable disagreement between the expected and the actual energy consumption. Consequently, the design parameters of power system components, such as capacity and endurance of battery, are too conservative or radical. Hence one can see that it is particularly important to accurately model motor efficiency and quantify its uncertainty when modeling the marine power system.
- Research Report > New Finding (0.48)
- Research Report > Experimental Study (0.48)
- Energy (1.00)
- Transportation > Marine (0.90)
- Transportation > Electric Vehicle (0.81)
Numerical Simulation and Model Test of VIM of Full Depth Mooring TLP
Hu, Wen Jia (Engineering Design Institute,CNOOC Research Institute Co.,Ltd, Beijing) | Wang, Shi Sheng (Engineering Design Institute,CNOOC Research Institute Co.,Ltd, Beijing) | Zhao, Jing Rui (Engineering Design Institute,CNOOC Research Institute Co.,Ltd, Beijing)
ABSTRACT Aiming at the VIM of traditional TLP and the VIV of tension leg and riser, the VIM of full depth mooring TLP is studied by combining numerical simulation with basin model test. According to the main scale parameters of TLP, the basin test model is made according to geometric similarity,and under the conditions of motion similarity and dynamic similarity, the model tests were carried out in cases of uniform flow, profile flow and wave current combined. The model test results are compared with the numerical simulation results to verify the consistency of the two. The results show that the lock-in range of VIM for TLP is 5.5 < Ur < 8.5, the incoming angle has a great influence on the VIM, and the wave has a certain weakening effect on the VIM and a strengthening effect on surge. The lift standard deviation and drag standard deviation of fixed flow increase with the increase of reduced velocity. The Research of paper can provide reference for the research and design of TLP.
INTRODUCTION TLP is a deep-water floating platform moored with tension legs, which bears external loads such as wind, wave and current during service. When the flow passes through the TLP, discontinuous vortex shedding occurs. When the vortex shedding frequency of the vortex is close to the natural vibration frequency of the platform, resonance will occur, which will induce large dynamic response of the platform and cause serious fatigue damage to the structure. The dynamic response of the platform is the superposition of the VIM of the floating body and the VIV response of the tension leg and the riser. They affect each other and have a complex nonlinear coupling relationship. The research methods of VIM mainly include numerical simulation and model test. Numerical simulation is based on the theory of viscous fluid mechanics. This method is convenient for parameter adjustment. Compared with model test,it has high accuracy and low cost. It is an important supplementary means of model test. Kim and Dusan(2015) investigated numerical sensitivity of the VIM response. The results show that applying the delayed separation eddy simulation(DDES) method can obtain more accurate prediction of VIM response amplitude. Chen and Chen(2016) used the finite-analytic Navier-Stokes (FANS) numerical method for the simulations of VIM of a deep draft semi-submersible. All the simulations and experiments indicate the peak nominal transverse amplitude at a reduced velocity of 6-7. Hu, Zhang, Li You (2021) used the Improved Delayed Separation Vortex Method to numerically simulate the VIM of a deep-draft semi-submersible platform.The results show that lock-in range of transverse motion under 22.5° and 45° flow angles is 6.0
- Asia > China (0.88)
- North America > United States > California (0.28)
- Research Report > New Finding (1.00)
- Research Report > Experimental Study (1.00)
- Reservoir Description and Dynamics > Reservoir Simulation (1.00)
- Data Science & Engineering Analytics > Information Management and Systems (1.00)
- Facilities Design, Construction and Operation > Pipelines, Flowlines and Risers > Risers (0.66)
- Facilities Design, Construction and Operation > Offshore Facilities and Subsea Systems > Floating production systems (0.54)