bluuebunny/crossref_metadata_2025_split huggingface dataset:
Validation of a Completion Digital Twin Applied to Packer Setting
Authors: Oliveira L. A. , da Silva F. R. G. , Bellumat E. , Gama W. C. , Costa M. V. F. , Donatti C. N. , Rosenbach L. I. N. C. , Fasolin K. , Martins A. L. 
Published: October 2023

Abstract
Open hole packers setting usually is performed running in hole the completion equipment and afterwards running a wireline operation to precisely check the packer position and make the needed adjustments to set it in accordance with the geological targets. The current digital twin software incorporates comprehensive models and it receives surface data in real time to analyze the current operation status, by comparing real and calculated (expected) data, with quantitative criteria. It allows the user to follow up the completion column running in hole, to make real time editions if any item needs to be replaced during operation (impact damage, measurement update, etc.). Torque and drag models allow to infer the completion column elongation and verify the real elements position within the well and based on integrity assessment the work window is calculated real time. The target depths are defined during drilling operations using logging data, then drill string elongation calculated with the drilling digital twin software was used to align the real reference depth in both scenarios, drilling and completion. With the real position of the packer in hole it was possible to define the stick up needed to adjust its position to the target depth before setting it. A validation was performed using three offshore real cases, where the packer position considering completion column elongation and the wireline results for packer position considering the pipe tag position detection were compared. In both approaches, a measurement for stick up was obtained to define the correct depth for packer setting and considered to be in good agreement. The novelty is the usage of numerical simulation to optimize the time spent to conclude the packer setting by avoiding an extra operation at the rig site, saving time, costs and operational risks.
Offshore Wind Power Plants in Brazil: Challenges and Opportunities for Port Infrastructure and Maritime Transport Logistics Sectors
Authors: Costa B. R. M. , Jaeger L. N. G. 
Published: October 2023

Abstract
Brazil has the potential to emerge in a leading position worldwide in the energy transition movement, especially employing renewable resources. In this scenario, wind power is one of the big bets to boost the generation of clean energy in the country. Currently, Brazil is the biggest producer of onshore wind energy in Latin America and the world's 6th country in wind capacity. This is due to the large wind flows, especially in the Northeast, South and Southeast regions of the country. In the offshore environment, it also has conditions to be a promising agent in wind power generation, with 7,367 km of coastline and 3.5 million km2 of maritime space under its jurisdiction, giving it favorable characteristics for the installation and operation of these projects. Moreover, it has an excellent position in relation to other emerging markets, due to its experience in the offshore oil and gas industry, onshore wind and civil construction sectors, in addition to the availability of raw materials (especially steel). The Brazilian potential has already been awakening the interest of investors on a large scale at the international level. Hence, this article shall bring a study mapping the challenges and opportunities in relation to the development of the offshore wind power generation market in Brazil, focusing on the port and maritime sectors.
Selection of High Temperature Scale Inhibitor for Squeeze Application in Indian Offshore Carbonate Reservoir
Authors: Uniyal Rishabh , Jaruhar Suman Kumar , Sarkar Manoj Kumar , Devshali Sagun , Parida Dibyajyoti , Bhoye Sushil , Biswas Sudipta 
Published: October 2023

AbstractThe paper aims to elucidate the process undertaken to identify suitable inhibiting chemical to prevent down hole deposition of scale in ONGC western offshore wells by means of a squeeze job. Detailed description of methodology adopted for chemical selection has been elaborated in the paper.Most fields in ONGC's Western Offshore region are brown/matured fields with depleted reservoirs pressures. Seawater injection is one of the primary techniques used to combat depleting reservoir pressure. This has led to rampant escalation in scaling issues in offshore limestone reservoirs and subsequently, the frequency of scale removal jobs has also increased exponentially over the past two decades. Scale prevention is a superior and economical alternative to scale removal due to lesser consumption of chemicals and prolonged life. As part of this study, the feasibility of carrying out Scale Inhibitor Squeeze Jobs in ONGC offshore wells was examined and subsequently, extensive laboratory experiments were performed to identify suitable chemicals. The experiments included inhibition efficiency tests, thermal stability tests and extended core flow studies (adsorption and desorption methods) to verify chemical compatibility with core sample of a number of generic and vendor based chemicals under simulated reservoir conditions.After a comprehensive literature review and market scouting, six Scale Inhibitors were shortlisted and evaluated for their inhibition efficiency, thermal stability and compatibility with the rock formation through laboratory experiments. After extensive testing, Chemical X was identified as being most suitable for scale squeeze job in carbonate formations having temperatures up to 110° Celsius (230° F) and was also compatible with the formation. The adsorption and desorption isotherms respectively demonstrated sufficient chemical retention in the core and slow elution in the discharge. The measured Scale Inhibitor concentration was found to be greater than the Minimum Inhibitor Concentration (MIC) required for scale prevention. This indicated that any potential squeeze job would likely have a reasonable expected life.The study explores the possibility of carrying out a first ever scale squeeze job in ONGC Western Offshore reservoirs particularly with high temperature application. Core flow experiments were performed using scale inhibitor chemical to derive adsorption and desorption isotherms used to prepare customized job plans.
Optimization of Coring Retrieval Process Using a Thermo-Poro-Elastic Approach
Authors: Silva T. V. , Riente A. F. , Binas F. A. V. , Barboza A. , Lima Santos J. P. 
Published: October 2023

Abstract
Cores can be considered the ground truth only if we eliminate or minimize their damage during the core cutting, tripping, and surface handling. During coring operation, while tripping out of hole, core is submitted to a relatively sudden decrease in pressure, leading to fluid expansion and movement out of the pore space. The rapidly expanding fluids can generate fractures and damage the core. Such damage would adversely affect their properties. In this paper an analytical approach model is introduced and applied to provide the maximal coring retrieval tripping rates. Ideally, core tripping rates should be established for each core, but common practice is based on generic rules of the industry. Traditional operating schemes do not justify the long tripping times.
With these high daily rig costs in mind, a more scientific and quantitative approach, tailored to each case is required. The Thermo-Poro- Elastic (T-P-E) geomechanical approach used in this study includes the diffusion time required for imposed pore pressure difference to dissipate while also considering the effects due to the temperature changes, the mud cake and swabbing during retrieval.
The hydraulic diffusivity and the fluid are the main factors that contribute to the maximum allowable safe tripping rates. A relationship between the hydraulic diffusivity and the decompression rate will be presented for each specified fluid type. For water-bearing cores there is almost no change in hydraulic diffusivity, on the other hand, gas-bearing cores and oil-bearing cores vary with depth.
This paper is a review of T-P-E analytical development and mathematical models to approximate the case of core tripping considering the effects of the pore pressure, temperature change, the mud cake, and swabbing. The model indicates that the fluid type and hydraulic diffusivity have been considered as the controlling factors. The analytical approach has been applied for modeling the tripping of water, gas, and oil-bearing cores to provide maximum allowable tripping rates.
WAG Optimization of Egg Model with Brazilian Pre-Salt Fluid Using PSO Algorithm
Authors: Freitas V. R. , Sánchez William Humberto Cuéllar , Lima G. S. , Pastrana M. A. , Barroso E. P. , Muñoz Daniel M. , de Almeida R. V. , Fortaleza E. L. F. 
Published: October 2023

AbstractWater Alternating Gas (WAG) is a consolidated enhanced oil recovery method that outperforms secondary recovery methods such as waterflooding or gas injection. Optimization of the WAG parameters can increase the cost function and improve revenues, but the algorithms usually implemented require high computational resources and time. In this context, a bio-inspired algorithm, Particle Swarm Optimization (PSO) is used to determine the best candidate for only two parameters, water and gas injection time, resulting in the determination of the WAG cycle and WAG ratio, thus drastically reducing the complexity of the problem. The proposed long-term optimization algorithm was applied in a modified version of a well-known reservoir benchmark Egg model, in which the fluid composition was adapted to resemble Brazilian pre-salt reservoir fluids and WAG injection. Moreover, it is shown that the best results obtained consider longer periods of water injection and improve the NPV by 5.5%.
Flow Assurance Analysis for Long-Distance Tieback
Authors: Sartor R. B. , Junqueira I. M. F. , Oliveira N. C. 
Published: October 2023

Abstract
This paper aims to present the results of long-distance tieback sizing connecting a manifold located 45km away from an FPSO through a multiphase flow steady-state simulation to present recommendations for sizing flow lines in terms of diameter, thermal insulation, flow, pressure, and service temperature, as well as the requirements for multiphase pumping (power, operating points, rotation, flow regime, fraction of gas in the suction, pressure differential, etc.).
With the results of the simulations, it was possible to observe the behavior of the fluid flow along the flowline and riser. In addition, we found an arrangement of multiphase pumps, based on an available catalog, that would allow the transport of the fluid to the FPSO. We faced the challenge of finding the adequate flow velocity, ensuring that the residence time as well as the adequate head loss of the fluid along the entire pipeline was sufficient to avoid temperatures lower than the paraffin formation temperature.
Based on stationary simulations, it was found that the flow temperature remains above 40 °C for higher production capacities. However, it is important to highlight that by reducing the production of the wells, the flow temperature may reach the paraffin point.
Another aspect observed in the stationary simulations was that the flow of the fluid tends to present a "slug" type behavior in the ascending section of the riser, especially close to the point of arrival at the FPSO.
Design and Experimental Identification of the Main Hydrodynamic Parameters for an Open-Frame ROV to the Peruvian Scallops Stock Assessment
Authors: Florez Paola Fonseca , Huamani R R. , Huanca Eber , Nina Wilder , Avila Juan Pablo Julca 
Published: October 2023

Abstract
This work presents the design and the experimental methods to identify the main hydrodynamic parameters for an open-frame underwater vehicle for the stock assessment of the Peruvian scallops. The added mass was determined from free oscillation tests in the surge, sway and heave directions with the reduced prototype model submerged in water and supported by springs. The acceleration data collected during the oscillations demonstrated that the equation of damped natural frequency gave a better approximation of added mass because of the fluid damping. The drag parameters in the directions of surge, sway, and heave were determined by two experimental methods in which the prototype was moved with constant velocities. In the first method, the prototype moved attached to a towing carriage through a water channel, and the second method consisted of applying different forces using the vehicle's thrusters that let it move. In both methods, the vehicle's velocity and force were known. The data collected led to determine the linear and quadratic drag parameters using the least square method. The results of the self-propelled tests were slightly different from those obtained in the towing tank because the thrust was not measured with the thruster installed in the prototype, being this in motion, confirming the importance of quantifying the interactions thruster- thruster and thruster-frame and the loss of force due to the vehicle's motion.
Integrity Management of Offshore Process Piping and Equipment with Sand Production – Part II: Remediations
Authors: Shirazi S. A. , Darihaki F. , Yamazaki Y. , Nakano Y. , Ushiguchi K. , Quang V. Lam , Ngoc L. Le 
Published: October 2023

Abstract
Sand production is challenging integrity issue that should be monitored to prevent interruption in the oil and gas production facilities. On the other hand, the limitations in the offshore platforms can contribute to the failure in the production system due to sand erosion. The objective of this study is to establish a practical framework of monitoring and a tool for generating Integrity Operating Window (IOW) thresholds, which are used for handling sand production in most safe and effective manner. The ultimate goal is to obtain the highest possible production output from producing wells while minimizing sand erosion related risks to as low as a reasonably practical level. The recommended monitoring measures of sand production, production rate and wall thickness are discussed as a part of sand management system. CFD-based models and mechanistic models are additional tools that can enhance this procedure. Erosion simulations of pipe walls indicated that the cushion tees that have replaced the piping with bends to prevent/reduce erosion rates are also susceptible to significant erosion. Therefore, wall thickness measurements are being conducted at critical locations. A simplified mechanistic model was employed to support developing sand erosion IOW prediction tool and determining monitoring locations, provided that a process for wall thickness measurements at critical locations is in place for verifying and fine tuning the models on regular basis.
Identifying Litho-Fluid Facies Using Machine Learning: A Case Study of Niger Delta Sandstone Reservoirs
Authors: Adeeyo Y. A. , Osinaike A. A. , Adun G. O. , Menkiti H. 
Published: October 2023

AbstractTo minimize uncertainties in reservoir characterization and modeling workflows, an accurate definition of reservoir heterogeneity, including lithologic and pore fluid variations, is required. Particularly because reservoir heterogeneity limits the spatial distribution of petrophysical and elastic properties used to understand the reservoir system or quantify its resource or storage potential. Traditionally, variations in reservoir rock and fluid properties are identified by interpreting depositional patterns and fluid content from core or cutting samples, or by applying statistical rock physics techniques to elastic well log data. However, collecting core data is costly, and both methods can be subjective, necessitating expert knowledge of sedimentological and rock physical principles to produce meaningful classification results.To overcome these limitations, we present a cost-effective and comparatively objective framework for identifying litho-fluid facies (LFF) using machine learning (ML) algorithms. Various statistical ML techniques were used for data-driven delineation of the LFF in the Niger Delta siliciclastic formation from a suite of commonly available geophysical well logs. The study followed a two-part process to arrive at the desired outcome. First, the target classes—clean hydrocarbon sand, shaly hydrocarbon sand, brine sand, and shale—were generated using a Dirichlet Process Gaussian Mixture Model (DPGMM) with Variational Inference (VI), an unsupervised clustering technique. These classes were subjected to probabilistic thresholding based on their log-likelihood and silhouette coefficient scores to obtain high-quality training samples. Following that, the training samples were used to construct supervised multiclass predictive models capable of generalizing the target LFF. Several classification metrics and charts were used to assess the accuracy and speed of the models to determine the model with the best predictive and computational performance.This ultimately revealed that the best-performing model was a single decision tree classifier with perfect metric scores, significantly high prediction probabilities, and minimal computational time. The random forest and gradient boosting classifiers performed similarly well on the task. Moreover, the use of analytical and statistical techniques throughout the process facilitated an objective and accurate differentiation of the rock and fluid types.The ability of the models to generalize to unseen data in a new well location with high predictive confidence makes it possible to characterize the spatially distributed facies in the study area with minimized uncertainty. Hence, we recommend the adoption of this framework for rapid and accurate LFF identification.
A Framework for Trustworthy Digital Twins Over their Lifecycle
Authors: Hansen O. H. , Jaiswal V. 
Published: October 2023

Abstract
Digital twins, replicating the physical assets they represent and working safely, effectively, and efficiently, can provide trustworthy results within well-defined limits and to a stated level of confidence. Capability and trustworthiness over time requires assurance processes and a methodology to assess and qualify the digital twin solutions. The purpose of a continuous assurance process is to ensure that the capabilities remain valid over time. A standard (DNV-RP-A204, 2023) for the qualification and assurance of digital twins has been developed and released recently. The framework in this standard was developed in close cooperation with the industry, including offshore floating and subsea facilities operators, and is currently being used across the energy sector by both technology vendors, engineering companies and operators.
The ability to execute a specified action or achieve a specified outcome, based on real time situational awareness and decision support, will define the capability level of the digital twin, moving from descriptive to predictive to automated. Digital twins are becoming more data-driven and digitalized and should be prepared for automated decision making.
The framework presented within the standard (DNV-RP-A204, 2023) addresses requirements to the functionality, technology integration, operations, the digital twin platform, including data quality and cyber security aspects, and requirements to the organization developing and operating digital twins. For each of these areas, clearly defined working and quality assurance processes and requirements have been defined and described.
Keeping a digital twin trustworthy and valid over time is a key challenge. The digital twin solutions need to be identified and managed as a key system, integrated in existing work processes, subjected to management of change processes, and continuously updated to accurately represent the physical asset at any time. All stakeholders need to implement tools and processes to monitor, assess and manage all relevant changes, which shall be verified.
This paper presents the philosophy and framework of the methodology from DNV-RP-A204 in the context of developing and operating a digital asset, as well as learnings from completed and ongoing projects.
Emulsion System with Nanoparticles for Selective and Reversible Water Shut-Off in Mature Sandstone Reservoirs Offshore
Authors: Sergeev V. , Abe M. 
Published: October 2023

Abstract
Results of laboratory research conducted in the framework of laboratory program developed jointly by a technology provider and an offshore oil-gas fields operator are presented in this paper. The laboratory program included optimal list of experiments for testing physical and technological properties of the physico-chemical water shut-off agent, resulting in a ready-for-pilot solution at minimum cost and time. The studied water shut-off agent is an emulsion system with nanoparticles (ESN), which is an inverse emulsion augmented by the synergy of natural and artificial surfactants with supercharged silicon dioxide nanoparticles. The ESN consists of three liquid components: sea water, diesel and nanoparticle-based surfactant. One of the main tasks of this research was to study such features of the ESN as selectivity of blocking impact to water-bearing zones and reversibility of blocking effect in the oil-bearing zones of sandstone reservoirs in the Lower Miocene (2950 psi and 91°C) and Late Oligocene (3900 psi and 107°C) hydrocarbon formations. As a basic requirement from the operator, the ESN had to be stable at the said reservoir conditions and compatible with reservoir and process fluids. Besides that, the operator wanted to confirm that the ESN is an easy-to-handle water shut-off agent in the offshore environment, meaning that it can be prepared with ordinary equipment available at the vessel, all components are liquids easily mixed to each other at ambient conditions and ready-to-use composition properties do not change in time within the operation offshore. Thus, the laboratory program was executed in three successive stages, divided based on the experiment conditions: ambient; pressure & temperature; modeled reservoir conditions. In result, the ESN performed as stable and compatible water shut-off agent and met all requirements of the operator. In the series of core floods, conducted on eight sandstone cores of different permeability and saturation, it was confirmed that the ESN selectively and fully blocks water-saturated cores, while the oil-saturated cores permeability decreased slightly with clear tendency to full recovery under the flow of hydrocarbons.