bluuebunny/crossref_metadata_2025 huggingface dataset:
Beyond Reality: Transforming Training with Virtual Reality
Authors: Dubois A. , Banda M. E. Yanez
Published: November 2024

This paper explores the innovative applications of Virtual Reality (VR) in training, highlighting its transformative potential in various fields. It examines how VR technology enhances learning experiences, particularly in sectors like drilling courses and geological field trips, revolutionizing traditional training methods. It discusses practical examples, benefits, and prospects of integrating VR into training programs, showcasing its ability to provide immersive, safe, and cost-effective learning environments.
Addressing the Complexities of Establishing a Comprehensive CO2 Storage Hub in the Large-Scale Saline Aquifer Offshore Malaysia
Authors: Tiwari P. K. , Das D. P. , Chidambaram P. , Tewari R. D. , Sedaralit M. , Md Noor M. Zaini
Published: November 2024

The rising CO2 emissions resulting from the development of high CO2 contaminated gas fields in Malaysia necessitate the identification of appropriate, secure, and capacious reservoirs for CO2 storage. Large-scale saline aquifers have emerged as promising solutions for establishing a storage hub equipped with extensive onshore injection facilities. Nevertheless, the development of a large-scale saline aquifer as a CO2 storage hub offshore Malaysia presents numerous intrinsic challenges. The current study focusses on identifying and evaluating the associated risks and uncertainties and formulating a mitigation strategy for the development of a large-scale storage hub within synrift sediments of a rift graben off the coast of peninsular Malaysia (PM).

When establishing a large-scale CO2 storage hub, it's crucial to prioritize two key elements: containment integrity and storage capacity. However, these components carry inherent risks that demand careful management throughout the storage development process. Containment integrity entails risks related to reservoir and overburden formations, structural features, and well integrity within the storage reservoirs. Conversely, storage capacity can be influenced by factors like reservoir continuity, aquifer size and strength, caprock strength, and injectivity.

The storage site was analyzed for its containment and capacity through extensive 3D data interpretation for generation of structural maps, mapping of major and minor faults, and attribute extraction, trap & seal analysis, faults & wells integrity analysis, 1D caprock integrity analysis, and effective storage capacity estimation through dynamic simulation. Dynamic simulation results of maximum storage capacity help deciding plausible mitigation plans, such as seismic data acquisition, appraisal well drilling, and coring, have been suggested to tackle these risks. However, quantifying the precise value added by these plans in terms of risk reduction presents a challenge. The workflow for this study to be used as the guideline for any future saline aquifer storage development plan feasibility study.
Real-Time Reservoir Insights: Advancing Data Accessibility with SW and PHIE Curves at Your Fingertips
Authors: Nestyagin A. , Al Mazrouei M. , Bandyopadhay I. , Ferrer A.
Published: November 2024

Objectives/Scope

Implemented for all drilling wells with zero cost the innovative reservoir data accessibility by making it possible to calculate and display SW and PHIE curves online in real-time. This innovative approach eliminated the need for special software and constant email updates, allowing all relevant parties to access up-to-date reservoir data from their PC or mobile phones. This project not only improved data accessibility but also increased efficiency and collaboration among team members.

Methods, Procedures, Process

Project aimed to innovate the way reservoir data is accessed by making it possible to calculate and display SW and PHIE curves online in real-time. The solution involved developing an algorithm and integrating it into an existing Real-Time monitoring software that could process reservoir data and generate SW and PHIE curves on the fly, without the need for special software or constant email updates.

The solution involved simplification of heavy software algorithms and integration it into the existed real-time monitoring platform at zero cost that could process reservoir data in real-time and generate SW and PHIE curves on the fly.

Results, Observations, Conclusions

The solution was implemented and rolled out to one of the fields in ADNOC Onshore, and the results were immediate. The team was able to access up-to-date reservoir data in real-time, without the need for special software or constant email updates. This improved the efficiency and collaboration of the team, allowing them to make more informed decisions in well placement and work together more effectively.

In summary, this project provided a solution to the challenges of accessing reservoir data by developing and integrating into the existing platform that could calculate and display SW and PHIE curves in real-time. This solution improved data accessibility, increased efficiency, and enhanced collaboration among team members. Making it possible to perform advanced geosteering in-house.

Novel/Additive Information

By making it possible to access essential Porosity and Water Saturation up-to-date reservoir data in real-time, even from mobile phone anywhere where you have internet network coverage, the project improved data accessibility, increased efficiency, and enhanced collaboration among team members. This allowed the team to make more informed decisions and work together more effectively in well placement.
Equipment Switchover and Overall Utilization Strategy
Authors: Alvarez Javier H. Sanchez
Published: November 2024

In the Oil and Gas industry, there are many different types of facilities, design for different stages in the hydrocarbon processing, comprised by multiple types of equipment in different arrangements, and while most companies share similar processes, facilities, and equipment they also have different visions on how their plants should be designed, how the processes are arranged, and how the equipment should be utilized.

During the preliminary design phase of an oil and gas facility, the input/output data is set and the process is licensed, then, the preliminary number of equipment required to fulfilled those process requirements are calculated and set. At this point, the RAM models are created and different scenarios are run to optimize the number of equipment to be installed in order to cover the process targets and also yield the maximum reliability levels to the plant. As result, the facility will have a number of installed machines that can be run in different patterns to meet production rates, while other remain in standby a precautionary measure should any unreliability event happened.

Following this logic, at any point in time some machines within a specific service will be running, while the rest are in standby; this fact had generated the need to elect how the machines should be utilized in order to keep them at optimal condition for operation. Whether we refer to the running machines or the idle machine, a solid equipment running philosophy should be developed to ensure every piece of equipment is available and ready to be used when needed.

To address this need, different companies in the industry had developed, deployed, and tested different approaches; while some companies assign one or more machines within the group as "Main", to continuously run to cover the duty of the service, similarly, the remaining machines are deemed as "Standby" and they are only used in the event that the main machine(s) are down for maintenance. On the other hand, other companies try to cover the service duty using all installed machines in an alternating running pattern, this approach aims to maintain the equipment reliability and availability by balancing the usage of all machines within same service.

Which philosophy is better? Well, that is very hard to answer, given that there have been multiple studies that support one strategy over the other; in this particular case, we will focus on the later, given the fact that for our organization the approach aiming for equipment utilization balance is one of the core objectives of the equipment utilization corporate strategy.

It is the objective of this document to present SGPD Equipment Switchover and Overall Utilization Strategy, starting with all the conditions that frame the program as well as the computational tools used to follow, control, and administer the equipment utilization.
Bridging the Gender Gap: Initiatives for Empowering Women in the Oil and Gas Sector in Abu Dhabi, UAE
Authors: Abudaqa Anas , Alsabiri Hassan , Alhammadi Sara , Almenhali Ahlam , Alkhawaja Ahmed , Alqubaisi Salem
Published: November 2024

Objectives/Scope

Our objective is to enhance gender balance in the oil and gas industry of Abu Dhabi by empowering female employees through structured initiatives. We aim to inspire, engage, and develop women professionals, addressing their unique challenges and fostering a more inclusive workplace.

Methods, Procedures, Process

Round-Table Discussions: Hosting sessions with female leaders to share their success stories and strategies for overcoming industry-specific challenges.

Executive Engagement

Organizing forums for open discussions between female employees and top executives (CEO and SVP) to address career progression and gather feedback.

Career Development Training

Conducting focused training sessions for young female employees to build essential skills, covering leadership, technical competencies, and personal branding.

Results, Observations, and Conclusions

Our initiatives have led to increased female employee engagement, improved morale, and a dynamic organizational culture. The open forums foster transparency and support, while the training sessions have prepared a robust pipeline of future female leaders. These efforts demonstrate the tangible benefits of diversity and inclusion in driving innovation and growth.

Novel/Additive Information

By sharing our experiences and best practices at ADIPEC 2024, we aim to contribute to the broader discourse on gender balance. Our comprehensive approach can serve as a model for other companies in the industry, showcasing effective strategies for fostering diversity and inclusion.
First Successful Field Test of Continuous Surveying While Drilling in Slim Hole
Authors: Anda Daniel Herrera , Hansen Christian , Hueper Andreas , Koenecke Andre , Gjertsen Morten , Pubanz Sebastian , Vogt Andreas
Published: November 2024

Definitive directional surveys are typically acquired off-bottom in a static environment using a measurement-while-drilling (MWD) tool embedded in the bottom hole assembly (BHA). The flow-off survey process can take up to 15 minutes. With continuous surveying it is possible to shrink the flow-off time to the drill pipe connection time, reducing the risk of stuck pipe events. Hence, it is desirable to take survey data continuously during drilling – covering a fine point grid along the borehole.

Although the concept of rotational continuous surveying (RCS) was introduced previously, the lack of proper digital signal processing within the surveying tool has made it impossible to cope with shocks and vibrations caused by the harsh drilling environment. Furthermore, the rotation of the drill string causes eddy currents to contribute an additional cross-axial offset and deteriorate results, if not properly compensated. Recent advancements in digital signal processing, algorithmic developments, and error modeling enable high-accuracy RCS. As the drill string is rotating, the raw sensor measurements from accelerometers and magnetometers are oscillating and cannot be averaged. Therefore, sensor measurements need to be transformed to allow filtering. Such a transformed survey set is created by calculating a complex envelope of the sensor signals. This approach opens the opportunity for rotational continuous surveying also for existing MWD survey tools.

As a quality assessment, RCS data from two wellbore profiles are compared statistically to static surveys by means of Chi-Square tests on direction (inclination and azimuth) as well as position, utilizing appropriate error models for static and continuous operational modes and correlation assumptions. The results verify that special attention should be paid to precise cross-axial sensor phase delay compensation prior to deriving a definitive continuous survey at surface. Such phase delays are caused by different filters in the magnetometer and accelerometer signal paths and the magnetic field induced by the eddy currents. Static-survey-like quality can only be achieved when phase shifts are correctly compensated. The paper presents results and case studies of continuous surveying with small diameter rotary steerable BHAs - an industry first. Fundamental principles, challenges, and relevant system components are outlined and a method for conducting downhole quality control is discussed. RCS has the potential to reduce costs and safety risks, and improve battery utilization, wellbore positioning, micro-dogleg detection, stuck-pipe prevention, and eliminate static survey time.
Autonomous Inflow Control Valve for Ultra-Light Oil and the Impact of Annulus Phase Segregation
Authors: Langaas K. , Gisholt E. , Mathiesen V. , Brekke K.
Published: November 2024

Autonomous inflow control valve (AICV) can make better and more carbon efficient oil wells. This paper publishes new experimental data for how an AICV handles ultra-light oil (0.8 centipoise), water and gas at full reservoir conditions. The paper also evaluates how phase segregation in the annulus outside the sand screens impact the effective zonal performance, and finally the impact of the tested valve on a typical thin oil rim infill target.

To verify the single and multi-phase flow behaviour of the AICV, a full-scale flow loop test was performed at down hole conditions. To understand and estimate the effective performance of several AICVs in wells with open annulus outside the sand screens, a newly developed lower completion modelling tool was used. The model includes phase segregation for a given well geometry and boundary conditions, and the result is integrated into industry standard reservoir simulators. Both the tested valve and an inflow control device (ICD) of similar choke strength as the AICV are "zonally upscaled" and evaluated for several infill well scenarios.

At various differential pressure the single- and multi-phase flow of oil, water, and gas rates were measured. The results show an AICV with high capacity for oil, while it chokes hard on both gas and water. The valve's performance was matched by the extended RCP function. The new lower completion modelling software calculates effective zonal performance accounting for phase segregation effects. As compared to the individual AICV performance, the effective zonal AICV-ensemble chokes harder for multi-phase flow. For the ICD's, the effective zonal performance change is opposite, with less choking at multi-phase flow. The effective zonal performance of the ICD-ensemble is well matched by the extended RCP function. The effective zonal performance of the AICV-ensemble cannot be matched by the same function, and a solution is to export the result as a pressure drop table. Test cases demonstrate the correctness of both methods. The infill well scenarios are inspired from a Norwegian oil field with thin oil rims and ultra-light oil. When compared with an ICD well, the well with AICVs reduce water production and increase oil recovery in all scenarios.

New experimental AICV performance data for ultra-light oil (0.8 centipoise) at full reservoir conditions is published here for the first time. Further, a new lower completion modelling method that accounts for phase segregation in the annulus outside the sand screens is used in this study. This gives new insight to the effective zonal performance of both ICDs and AICVs and improves the production forecasts from wells with such technology.
Deployment of Customized Multi-Purpose Offshore Vessel with Dynamic Positioning Capabilities in Large Scale Well Intervention Operations
Authors: Bakir Hamadeh , Elsayed Hany
Published: November 2024

Offshore oil and gas operations are inherently complex, requiring advanced technological solutions to ensure efficiency, safety, and reliability. One of the key innovations that have transformed offshore operations is Dynamic Positioning (DP) systems. These systems enable vessels to maintain their position and heading using their own propellers and thrusters, which is essential for operations demanding high precision and stability, such as large-scale well interventions.

Well interventions are critical to maintaining and enhancing the productivity of oil and gas wells. These operations, which can include well testing, stimulation, and acid treatments, are traditionally carried out using conventional barges or fixed offshore installations. However, these methods have several limitations, including restricted mobility, reduced operational efficiency, and challenges in performing complex, simultaneous operations.

The deployment of customized multi-purpose offshore vessels equipped with DP capabilities has emerged as a solution to these challenges. These vessels can perform a wide range of operations, including well testing and stimulation, while maintaining position accurately even in adverse sea conditions. This capability not only improves operational efficiency but also enhances safety and reduces the environmental impact of offshore operations.
Ionic Liquid-Based Formulation for Inhibiting Calcium Sulfate Scale in High-Pressure High-Temperature Wells
Authors: Murtaza Mobeen , Budiman Ose , Kamal Muhammad Shahzad , Alajmi Shabeeb N. , Al-Jawad Murtada , Mahmoud Mohamed
Published: November 2024

The persistent problem of sulfate scale formation in oil and gas operations, primarily involving anhydrite (CaSO4) and barite (BaSO4) scales, poses significant operational challenges. These scales, resulting from mixing incompatible waters rich in sulfate ions with calcium or barium ions, obstruct fluid flow and cause substantial damage to production equipment. The conventional commercial solutions to this issue, such as the use of acids, chelating agents like Hydroxamic Acid and EDTA, and mechanical methods like pigging and downhole tools, are often hampered by limitations including high costs, high-temperature, environmental concerns, and limited effectiveness against certain types of scale. To overcome the existing challenges, an innovative approach using an ionic liquid as a scale inhibitor was introduced in this study. The chosen ionic liquid, 1-Butyl-2,3-dimethylimidazolium hexafluorophosphate (1B3DM6FP), is specifically introduced to target sulfate scales. This environmentally friendly solution offers a more efficient approach for managing scale formation, particularly at high-temperature conditions encountered in deep wells. To evaluate its effectiveness, we conducted a series of static bottle experiments, providing an in-depth analysis of the inhibitor's ability to prevent scale formation and its interactions with scale-forming ions. The first time, the performance of 1B3DM6FP was thoroughly examined at temperatures of 150°F and 320°F over an extended period. The results from these tests indicate that 1B3DM6FP exhibits substantial potential in inhibiting sulfate scale formation, outperforming traditional methods in several key aspects. The performance of IL at high temperatures is substantially high due to its higher thermal stability. The IL proved to be a stable scale inhibitor for several days. The scale inhibition potential was in direct relation with the concentration of the IL means higher inhibition was achieved with higher concentrations. 1wt% IL resulted in blank solutions without any scale after almost a week of ageing. IL application could mark a significant advancement in scale management strategies within the oil and gas industry, highlighting a shift towards more sustainable and effective solutions at high-temperature conditions. This study not only underscores the challenges of sulfate scale management but also emphasizes the importance of innovative approaches like the utilization of ionic liquid (1B3DM6FP) as an efficient and green scale inhibitor.
Unleashing the Power of Generative AI and LLM for Training Evaluation
Authors: Tharayil Sarafudheen M. , Idris Muhammad Azmi , Alfaifi Osama M. , Alghafis Muhannad S.
Published: November 2024

This paper presents a novel approach to training evaluation using Language Models (LLM) and Generative AI (GenAI) to build a classification model. The study aims to develop a resource-efficient solution for analyzing training rubrics and transcripts, thereby enhancing the assessment of learning outcomes and performance. The methodology involves data collection, preprocessing, model fine-tuning, prompting, and evaluation. A pre-trained LLM model is fine-tuned on preprocessed training rubrics and transcripts, allowing it to adapt to specific language patterns and structures. The model generates prompts to classify training materials based on predefined criteria, with domain expertise incorporated for complex evaluation rules. Results demonstrate a 60% reduction in processing time for evaluating rubrics and transcripts compared to manual assessment. The implemented model has significantly reduced the workload of the training department and improved the efficiency of data analysis. Furthermore, the model's feedback has led to targeted improvements in training content, resulting in higher learner satisfaction. This innovative application of LLM and GenAI in training evaluation offers a new perspective on leveraging AI to enhance educational processes and outcomes in a resource-efficient manner.
Hail and Ghasha Carbon Capture and Hydrogen Recovery: a Unique Perspective
Authors: Al Suwaidi M.H. , Signorile C. , Miranda De los Santos L. , Patansaongikar A. , Giri N. , Shah H.
Published: November 2024

This paper will present ADNOC's Carbon Capture initiative on Hail and Ghasha Development Project (HGD), through a description of the selected process line up for CO2 recovery, transportation and delivery, and the analysis of the overall asset emissions for the development scheme.

HGD is currently in the execution stage and will develop the untapped oil and gas reserves from the highly sour Hail and Ghasha fields. Production is targeted to start by Q1 2028 (January 2028) with sustainable production of 1 BSCFD of raw gas, and max production of 82.5 MBPD of Oil, 76.3 MSTBD of Condensate, 9000 TPD of Sulphur and 5030 TPD of NGL. The sour gas levels at Hail and Ghasha fields are exceptionally high, in the range of 13 to 38% mole H2S, and 4 to 9% mole CO2.

The raw wet sour gas coming from offshore Ghasha wells via GOP and production fluid from Hail offshore wells will be commingled in Onshore Processing Plant (OPP) and treated at Acid Gas Removal Units (AGRU). The acid gas will be processed in an oxygen-enriched Sulphur Recovery Unit (SRU), to recover elemental Sulphur. The off-gases from TGTU absorbers, having 73% mole CO2, 20% mole H2, etc., will be compressed and fed to ‘H2/CO2 recovery section’, to recover H2 and CO2 as high-purity streams through cryogenic and PSA technologies. The recovered H2 will be used to feed the Condensate Hydrotreater Unit, while the CO2 will be compressed for reinjection, and delivered through 140 km pipeline to BAB Hub (ADNOC Onshore), where it will be re-injected.

As result of this line up, from the ‘H2 / CO2 recovery section’, only off-gases will be sent back to SRU/TGTU Thermal Oxidizers (Incinerators), hence significantly reducing the CO2 emissions to atmosphere, and playing a fundamental contribution towards achieving project Net Zero emissions.

It should be mentioned that the lineup is covered under the ADNOC patent application EP4319903A1 "Method and system for Sulphur, Carbon Dioxide, and Hydrogen recovery".
Driving Tech Enhancement Through Capability Dialogue
Authors: Al Mehairbi F. O.
Published: November 2024

The energy sector is a dynamic landscape in which organizations are committed to driving technological enhancement by means of a strong framework of capability dialogue. This paper discusses how knowledge sharing tools can be strategically leveraged to foster an open, supportive communication environment that supports a culture of continuous improvement and enhances employee's engagement levels. The article also outlines how this facilitates the development of a collaborative learning ecosystem through which employees in different areas of the organization can learn from one another.

By ensuring more meaningful and effective learning and development programs, emphasis on capability dialogue guarantees that subject matter experts (SMEs) get involved in these programs leading to seamless transfer of expertise as well as best practices. Such involvement aids individual growth and improves collective organizational capabilities. Our aim is to bridge skill gaps and raise technical proficiency across the entire workforce through structured learning interventions, focused training programmes, and mentoring initiatives.

The importance of integrating with state-of-the-art learning methodologies for sustainability is underscored by this research. It focuses on the role played continuous professional development (CPD) as well as personalized learning paths have within an organization towards nurturing a highly skilled and adaptable workforce. Commitment to fostering a culture centred on learning drives operational excellence and innovation so that organizations remain on top in their respective industries. Further, the paper discusses digital transformation's influence on learning experiences as well as the need for adaptive educational technology capable of keeping up with industry changes.
Strategies for Minimizing Scope Changes in Project Management: Case Study of Jafurah Downstream Pipelines Project
Authors: Alqahtani Matlaq M. , Alsulaiman Salem M. , Alomair Anwar A. , Harbi Adel N.
Published: November 2024

A prevalent difficulty in project management is uncontrolled changes or constant growth in a project's scope. Stakeholder misalignment, inadequate risk management and undefined scope in the early stages of the project are some of the main challenges that frequently results in missed milestones, cost overruns and overall project derailment from intended plan. This paper presents a case study for Jafurah Downstream Pipelines project, a mega project under Jafurah Development Program in Saudi Aramco.

Software based tool was efficiently used to implement exchange of information and interface agreements to manage the constant design development during the execution phase. Global Interface meetings were organized at regular intervals to align program stakeholders, contractors and project entities within the company. Moreover, numerous Value Improving Practices (VIPs) have been conducted beside the lessons learned utilization of Front-End Engineering Design (FEED) verification reports for similar pipeline projects. Focus teams formed to perform extensive site visits periodically for brownfield areas to assure the functionality of design reflected the actual conditions.

As part of an accelerated program, adopting such techniques can be overlooked due to time constraint and excessive workload, however, positive gains in project performance will far outweigh the costs of utilizing teamwork to implement these strategies.
Time-Lapse Surveillance of Multiphase Reservoirs in Harsh Environments Using Heat-Flask Next-Generation Pulsed Neutron Logging Technology
Authors: Kim Y. , Kotov A. , Chace D. , Sluis R. van der
Published: November 2024

Heavy oil production often requires a thermal recovery technique. An accurate understanding of the current reservoir fluid components in the post-steam injection stage is essential for evaluating the efficiency of the thermal recovery process and making timely reservoir management decisions. This paper presents the characterization of steam propagation and subsequent heavy oil and water redistribution in a thermal recovery process using heat-flask next-generation pulsed neutron (PN) well logging technology.

We developed a next-generation multidetector PN tool equipped with a heat-flask housing for logging wells where the thermal heavy oil recovery process is implemented. The key features of the next-generation PN tool include upgrading a pulsed neutron generator (PNG), denser and higher gamma-ray count rates, higher-resolution lanthanum bromide (LaBr3) detectors, and a digital electronics system. These improvements in the tool enabled faster acquisition of the required pulsed neutron data without sacrificing data quality. Moreover, these enhancements allowed the simultaneous acquisition of two different types of PN measurements, which historically required two separate logging runs. The two primary datasets are (1) a salinity-independent time-spectra-based gamma-ray ratio measurement sensitive to the steam volume and (2) inelastic energy-spectra-based C/O ratios that mainly differentiate oil from water.

Tool-, well- and reservoir-specific forward modeling of two PN measurements was performed using the Monte Carlo N-Particle (MCNP) method. Two salinity-independent nuclear data and predicted stochastic models were integrated to quantify multiphase formation volumes simultaneously.

We present a case study of time-lapse monitoring of steam-flooded heavy oil reservoirs using legacy and new PN tools in a steam-assisted gravity drainage (SAGD) project. Before steam injection, a base log run was acquired to identify the unperturbed heavy oil distribution. Subsequent logging runs were performed after steam was injected. A comparison of the acquisition time and data quality from the previous- and next-generation PN tools revealed that equivalent quality data were recorded at least three times faster with the next-generation tool than with the previous-generation tool. Furthermore, PN surveillance revealed steam chamber growth and heavy oil distribution profiles.

With the introduction of the next-generation PN tool and heat-flask housing, PN well logging in harsh environments at temperatures exceeding 175 degrees Celsius (or 350 degrees Fahrenheit) became efficient. In addition, compared with the conventional sequential approach, an innovative PN data analysis technique effectively characterized and quantified three fluid components with the simultaneous use of two PN measurements.
Numerical Simulation of Welding Temperature Field and Stress Field of Offshore High-Strength Steel
Authors: Huo Guojing , Yu Boqian
Published: November 2024

Objectives/Scope

With the extensive development of offshore installations, an increasing number of offshore structures are constructed using high-strength steel. The high-strength steel is susceptible to welding residual stress. And it is cost-prohibitive to rely solely on welding experiments. Therefore, utilizing numerical simulation technology to investigate the welding process of offshore high-strength steel holds significant scientific research value. The research aims to study the influence of process parameters on welding temperature field, residual stress and deformation by the finite element method.

Methods, Procedures, Process

In this paper, a three-dimensional model of a V-groove welded joint of offshore high-strength steel was established using Ansys software. And the welding process was simulated with a volume heat generation heat source. The bidirectional coupling between the temperature field and stress field during plate butt welding was analyzed using a direct method. The influence of welding current on the temperature field and stress field in high-strength steel butt welding was investigated while keeping the welding voltage and speed constant.

Results, Observations, Conclusions

Firstly, the distribution of temperature fields in the weld and base metal was analyzed. The temperature in and around the molten pool was the highest, and the heat was gradually transferred outward. The increase of welding current directly resulted in an increase of welding heat input, leading to a higher peak temperature field. Furthermore, the evolution of residual stress distribution under different welding currents was examined. The peak residual stress increased with temperature, particularly the residual compressive stress at the weld position, causing the changes of the stress state along the weld center line in the X and Y directions. The deformation and displacement of welded joints were obvious in macroscopic view.

Novel/Additive Information

The mechanism of welding is complicated, and its application in the offshore high-strength steel has great prospects. The simulation results can provide some theoretical guidance for the optimization of welding process parameters of offshore high-strength steel, which has great practical significance and economic value for improving the quality of welded joints.
Optimizing Solar Panel Tilt Angle and Direction for Maximum Efficiency: A Comprehensive Analysis
Authors: Talele Harshal
Published: November 2024

The solar photovoltaic (PV) is considered to be the one of the most promising energy source in many applications, due to its safety and high reliability. But the initial high cost of the PV arrays and the large area necessitate their optimum use.

The maximum theoretical limit (known as the Shockley-Queisser limit) for silicon p-n junction cells is 33.7% and most current commercial PV cells manage between 15 and 22%. The declination angle δ=−23.45°×cos(360/365×(d+10)) of the sun changes due to the rotation of Earth about an axis form maximum value is 23.45° on 21 December and the minimum is −23.45° on 21 June. One of the solutions that optimize the array performance is to adjust the array tilt such that the incident insolation on the array is maximized. The best results are obtained when the movement of the sun is tracked both on a daily and seasonal basis. However, as this scheme is costly and involves complex control, alternative solutions have been sought for.

In the simplest way, the PV panels are inclined at the latitude angle of the site, throughout the year. Many researchers found that latitude angle is suitable angle for PV panel tilt angle. However, it is observed that a decrease in the tilt angle than latitude angle in summer and an increase in the tilt angle in winter enhances the solar energy received on the panels significantly. Optimal tilt angles and corresponding monthly solar insolation values have been compared among latitude angle, fixed tilt angle, and bi-annual changing (fixed twice a year). The changing solar panel tilt angle twice in a year gives maximum power output.
Advanced Rock Mechanical Characterization of Giant Cretaceous Carbonate Sequence for Reservoir Development
Authors: Noufal A. , El Wazir Z. , Al Madani N. , Shinde A. L. , Benmamar S. , Perumalla S. , Aldin M. , Govindrajan S. , Gokaraju D.
Published: November 2024

Advanced rock mechanical characterization of a giant Cretaceous carbonate field in Abu Dhabi is the focus of this paper, that not only focused on routine triaxial tests for shear strength estimates but also to understand pore collapse, tensile strength, thermal and creep behavior of these rocks.

The approach has started with auditing and selection of core intervals from various offset wells. These core intervals are selected to represent lateral and vertical coverage of various sub-units within various reservoir and caprock intervals. Scratch tests and whole core CT scans are conducted for selection of appropriate intervals for extracting core plugs. Specialized techniques are deployed for plugging the core intervals. Pre and post-test photographs and CT scans of all the plugs are taken to identify the role of heterogeneity.

The testing program encompasses various triaxial tests such as single stage (SST), multi-stage (MST), and unconfined compressive strength (UCS) tests. They are crucial for understanding rock shear failure, strength parameters like UCS, cohesion, friction angle, and stiffness properties including Young's modulus and Poisson's ratio. Acoustic velocity is also recorded during these tests. Additionally, tests like uniaxial pore volume compressibility (UPVC) and Biot are performed to ascertain the compressibility and poro-elastic coefficients. Hydrostatic compaction tests provide insights into pore collapse onset, while Brazilian tests measure tensile strength, and fracture toughness tests assess resistance to crack growth. We also conduct thermal expansion and creep tests to determine the rocks’ thermal behaviour and time-dependent deformation characteristics.

Based on the results of rock mechanics testing program, mechanical rock properties correlations have been developed for various reservoir units and caprock. These correlations demonstrate a relationship between geomechanical and petrophysical properties. The developed bespoke correlations have been successfully used across different wells, demonstrating accurate core-log calibrations of mechanical rock properties. This high-level characterization of carbonate reservoirs and caprocks aid in comprehending rock behavior under various field development conditions: such as reservoir depletion, fluid injection, potential CO2 sequestration, and modeling of thermal and creep phenomena.
Performance Analysis of Digital Underreamers in Motorized Bottom Hole Assembly
Authors: Ashish Sanan. , Singh Bagga. Pawandeep , Mansi Maheshwari.
Published: November 2024

Expandable reamers were developed to enhance operational efficiencies and minimize risks during the drilling process in challenging formations found in deep-water and offshore wells. These tools are particularly valuable in addressing the significant challenge of ensuring wellbore stability in such environments. The initial concentric expandable reamers were activated by a ball mechanism, and once expanded, they remained open until circulation was halted. In the subsequent version, modifications were made to enable deactivation, allowing circulation even after reaming for improved hole cleaning. The concentric expandable reamer offered several advantages over its mechanical-arm predecessors. These included the ability to achieve a larger borehole size to accommodate larger bottomhole assembly (BHA) components, flexibility in choosing pilot bits, higher flow rates, and the capability to ream a previously drilled hole or back ream a hole after drilling.

The digitally controlled, expandable under reamer, activated as needed, is seamlessly incorporated into BHA and can be remotely monitored and managed from the surface. Real-time feedback from the reamer includes data on tool vibration and stick slip (VSS), along with confirmation of blade activation status and precise blade position (fully retracted, fully extended, or in transit between the two positions). The extended blade position is pre-set to a specific surface position, and upon activation, the reamer opens to this position to initiate reaming operations. This real-time feedback minimizes operational uncertainties during reaming, streamlining the shoulder test process and saving time.

With unlimited activation cycles, the reamer offers the capability for selective reaming. The flexible arrangement of multiple reamers within the BHA allows for both near-bit and main reaming applications. Intense study of Bit and Cutter on reamers is needed to deliver wells flawlessly. Also, the motor on top of reamer provides sufficient RPM to obtain drilling performance.

The paper discusses in detail the concept of Installing the underreamer below the mud motor and showcases how it worked successfully in four recent wells, saving a trip for the operator in each well. The paper will also compare multiple Bottom Hole assemblies where the concept of Motorized Underreamer was used with wide range of well profiles including vertical to highly deviated wells. Every well had its own challenges and Intense pre job planning was done to successfully complete the wells. The target depths of well ranged from 2500m to 5500m. Body text 2 paragraphs.
Development of a Risk-Based, Modelling Framework for Integrity Assessment of Legacy Wells in CO2 Storage Applications
Authors: Ghanbari S. , Sefat M. H. , Davies D. , Murray J, , Bonfanti R. Oropeza , Martin I.
Published: November 2024

Demonstrating the integrity of Plugged and Abandoned (P&A'd) legacy wells during CO2 storage projects is a crucial requirement for regulators, stakeholders, and operators. The corrosive nature of CO2 may affect the integrity of such wells, jeopardising the long-term containment of the CO2. This study illustrates the new capabilities, tailored for CO2 storage applications, of a modelling framework (Johnson et al, 2021a&b) that provides a quantitative, risk-based assessment of the long-term integrity of legacy P&A'd wells. The following three new modelling modules are added to this integrated framework to account for the key concerns due to the presence of CO2 in the system:

The cement-CO2 geochemistry "add-on" module evaluates the phenomenon of cement's self-sealing/self-degradation behaviour. Carbonated water reacts with cement minerals; some of which are initially dissolved followed by a possible precipitation process that is controlled by the fluid's flow rate/residence time in the cement defects such so microannuli. The self-sealing mechanism can reduce the microannuli's width, potentially stopping CO2 leakage, while self-degradation has the opposite effect. The geomechanical "add-on" module quantifies changes in the size of defects within the well P&A system when the pressure/stress changes during the CO2 storage process. Pressure/Stress variations change the radius of the casing and the size of the adjacent microannuli, altering the leakage rates within the legacy well system. The elastic/plastic stress behaviour of cement can potentially contribute to increasing risks. The CO2/casing corrosion "add-on" module estimates the rate of casing corrosion and subsequent reduction in casing thickness over time based on experimental data. Excessive corrosion can lead to casing breach. These processes increase the size of defective leakage paths and increase the leakage risk from the legacy well.

On completion, the modelling framework will be capable of being an integral part of the risk-assessment process when (a) selecting between possible CCUS projects and (b) supporting operators, regulators and other stakeholders in their decision-making process when analysing CCUS proposals.
A Practical Approach to the Numerical Simulation of Vertical Wells with Negative Skin Factors on Fine-Scaled Grids
Authors: Saadawi Omar , Hirakubo Yasushi
Published: November 2024

In a numerical simulator, the inflow from the reservoir grid into a producer well is governed by well connections. The transmissibility of each well connection is calculated using a connection transmissibility equation. On Cartesian grids, the pressure equivalent radius ro is calculated using Paceman's formula. To ensure the denominator of the transmissibility equation remains positive, it is necessary for the term ln(ro/rw), where rw is the well radius, to be greater than the dimensionless skin factor S.

However, when using fine-scale local grid refinements (LGRs) and reducing the grid block size, the term ln(ro/rw) approaches zero, limiting the effective magnitude of the negative skin value. Increasing the grid size can overcome this issue, but for certain cases smaller grid sizes are necessary to accurately model the flow from the reservoir into the well. This paper aims to present an alternative practical approach to address this problem by applying a permeability multiplier to a "skin zone" across the near-wellbore grid cells, while still accurately equating it to an equivalent dimensionless skin factor.

To demonstrate the proof of concept, a simple 2-dimensional, homogeneous, water-bearing, single-well, numerical model was created. Various cases were simulated with different grid sizes, skin zone multipliers, and skin zone radii. An equivalent analytical model using the infinite-acting radial flow equation was then used to develop a relationship between the analytical skin factor and the numerical skin zone (multiplier and radius) for different grid sizes. A clear correlation was found between the analytical model and the numerical model of the simple 2-dimensional model. Using this correlation, the work was successfully extended to real field tests.

Based on the results of this work, the following conclusions can be made. As the grid size is reduced in the numerical model, the minimum effective skin factor ‘S’ increases. The minimum effective skin factor for a given grid size can be calculated analytically using the well radius and the grid dimensions. An equivalent "skin zone" (i.e., permeability multiplier in a defined area around the wellbore) can be used on any grid size to replicate the analytical model skin factor. A correlation has been developed to identify the necessary skin zone permeability multiplier and skin zone radius to replicate negative dimensionless skin factors for vertical wells on fine-scale grids.

This work demonstrates a practical and reliable alternative for reservoir simulation engineers to numerically simulate vertical wells with high negative skin factors on fine-scale grids. A mathematical correlation is presented to inform the engineer of the required skin zone radius and permeability multiplier necessary to model the equivalent negative dimensionless skin for various fine-scale grid sizes.
ESP Successful Optimization Using Variable Frequency Drive Current Limit with Combined System Technique, Production Enhancement in Colombia Llanos Field
Authors: Martinez Yuly , Figueroa Paula , Castro David , Garzón Miguel , Ariza Iván , González Camilo , Aguinaga Pilar , Devia Nestor , Mazabel Katherine , Jaramillo Javier , Camelo Sebastian
Published: November 2024

One of the main challenges during the operation of an ESP system is to achieve a stable production, this can be guaranteed by an appropriate monitoring of electrical and downhole sensor parameters. However, the conditions of a field located in the Llanos Orientales Basin in Colombia, where there is high presence of free gas in the T2 and comingled K1-T2 formations, cause high instability in the operating parameters of the ESP systems, leading to several shutdowns and causing high levels of deferred production. In the past, the configuration of motor current controls and PID algorithms in the variable speed drives were not enough to achieve smooth operation causing premature ESP failures and incurring in high well intervention costs.

This paper describes a successful study case of the application of the limit control parameter in the variable speed drives for the Llanos field (area Apiay) operated by Ecopetrol and offers a different approach to running the limit controls on the drives. With this methodology, smooth operation was achieved in several challenging wells, increasing the system efficiency, while extending the equipment run life and avoiding costly workovers.