bluuebunny/crossref_metadata_2025_split huggingface dataset:
Offshore Wind Turbine in China: Overview, Research Trends, and Challenges
Authors: Li Chengxi , Singh Harpreet , Cheng Peng , Wang Xunjie , Hao Ge , Liu Qing 
Published: April 2023

Abstract
China's wind energy resources are abundant. Its exploitable wind energy reserves are about 1 billion kW(Burrows 2020). Among them, the offshore wind energy reserves that can be developed and utilized are about 750 million kW(Burrows 2020). Historically, the price of offshore wind turbines has been significantly high. However, its cost decline is accelerated due to significant technological advancements. Recently, offshore wind power can compete with China's coal and nuclear power in terms of cost. This study aims to provide a detailed review of the current status, research trends, and challenges of offshore wind turbine development in China.
Currently, the offshore wind turbine with the largest single-unit capacity released in China has reached 8 MW and will soon enter the 10 MW era. The most common offshore wind turbines in China are Gravity-based, Monopile, Jacket, and Tripods offshore wind turbines in shallow water, and SPAR buoy, Tension leg platforms, and semi-submersible in deep water. This paper first included an overview of these offshore wind turbines’ system functionalities, features, strengths, weaknesses, and case studies. We then focus on the critical technologies for developing offshore wind turbines in China. The current technology status of the major operators is also summarized, representing the most advanced technology on the market. At last, we briefly summarized the future research directions of offshore wind turbines.
In this study, we first gave an overview of offshore wind turbines currently on the Chinese market with several case studies. From these case studies, we recognized the critical technologies needed for the further development of offshore wind turbines. These technologies include hydraulic pitch technology, optimization design of the supporting structure for large-scale offshore wind turbines, offshore wind farm layout optimization, offshore power transmission, and intelligent operation and maintenance technologies. This study presented and analyzed these key technologies’ technical value, significance, development trends, and application scenarios.
This paper introduced offshore wind turbines and related case studies in various fields with different operational conditions in China. We extracted and summarized the critical knowledge and technologies from these case studies for current practices and future work, facilitating operators to understand and develop these technologies efficiently.
Vertical Exploration Approach for Seafloor Massive Sulfide Deposits
Authors: Wegerer Stefan , Semel Matthias , Weixler Leonhard 
Published: April 2023

Abstract
The transition towards renewable energy and the electrification of various industry sectors will undoubtedly lead to higher resource demand of our society. Metals like copper, cobalt or rare-earth metals are the basis of these new technologies. However, these elements are not yet available in sufficient quantities in our economic cycle. Hence, more material would be required to be extracted from open pit land mining. A suitable and promising alternative to land deposits are seabed mineral resources. The focus of this work is the development and analysis of a new method to explore seafloor massive sulfides (SMS) with regards to minimizing footprint of the operation in all aspects.
SMS reservoirs are mostly found in water depths between 2000m and 4000m. To explore these deposits in the deep sea a concept study based on a vertical trench cutting system has been developed. The extreme environmental conditions require mechanical calculations of the template stability on highly inclined slopes. Furthermore, the cutter tool performance and wear behavior are investigated on a test stand through cutting into rock probes, which have comparable mechanical properties as massive sulfides. The technical feasibility of the separation system was analyzed by computational fluid dynamic models simulating multiple-phase flow and its behavior.
For bulk sampling of massive sulfides two potential concepts were examined and compared against each other. The main difference is the conveying method of the sample material to the ocean surface. A discontinuous lifting system with a collector bucket has major advantages in contrast to a riser system. During short exploration campaigns substantial energy and cost savings were estimated for a mechanical intermittent ore transportation. The first results regarding the effectiveness of the separation container could be demonstrated. The separation process takes place in a large scale hydrocyclone in-situ on the seafloor. The ground stability for the landing and leveling of the deep sea sampling unit was verified.
Key aspect of the vertical trench cutting approach is the minimal environmental impact during the whole exploration phase. At the same time this system enables to retrieve large amounts of sample material in an economical way.
A Macro-Scale Generalized Search and Rescue (SAR) Model for the Coastal Regions of Eastern Canada and the Arctic
Authors: Zarrin Mehr Mohammad , Molyneux David , Smith Jennifer , Pelot Ronald , Goerlandt Floris , Brown Robert 
Published: April 2023

Abstract
Given the complexity of Search and Rescue (SAR) activities in the coastal regions of Eastern Canada and the Arctic, there is a need to objectively assess system capabilities at a high level to determine the expected rescue time for multiple scenarios and system configurations. This paper outlines a new macro-scale generalized SAR model to simulate the main activities within the SAR system in Eastern Canada and the Arctic. The model uses discrete event simulation to represent the SAR operations and a probabilistic Monte Carlo approach to incorporate uncertainties in performance data for the different components of the system. Algorithms are first developed to identify the major decision-relevant components of SAR response, including the time to interpret emergency notifications and mobilize helicopter resources, the operability of assets in given environmental conditions, and the proximity and capability of resources. Following this, the model is coded in MATLAB, using a time-stepping approach, enabling changes in the scenario, asset status, and system configuration at any time step. Case scenarios are used as initial verification, beginning with a simplistic approach, and building complexity in the model parameters.
For this paper, we will discuss simple and complex scenarios which are based on common incident occurrences and SAR system operational details in eastern Canada's coastal regions and the Arctic. We assess the sensitivity of the overall SAR system to various input parameters to better understand how factors such as the Location of Incident (LOI) and number of People in Distress (PID) influence SAR response time in remote coastal areas, as well as the impact of refueling station locations for more distant and longer duration scenarios.
Introduction of Azipod DI and ESS for Icebreakers
Authors: Hanninen Samuli , Hakala Jani , Viherialehto Sampo , Maattanen Pirjo , Heideman Torsten 
Published: April 2023

Abstract
Polar multi-year ice thickness and extent will continue to reduce, and the traffic volumes in polar seas are expected to grow. Since the first podded propulsion was installed in an icebreaking vessel more than 30 years ago, Double Acting ships have delivered excellent results, revolutionizing the design and operations of icebreaking vessels. After that a completely new fleet of Double Acting tankers and icebreaking support vessels have successfully proven their abilities. The same development has enabled even larger and more capable ice vessels. Podded propulsion is an attractive solution, making these innovative icebreaking ship concepts technically and commercially feasible.
The Finnish icebreaker Polaris is one of the most advanced ships in its class. Innovative designs were used for the vessel's hull form and propulsion unit arrangement. The vessel can use either liquefied natural gas (LNG) or low Sulphur diesel oil as fuel. The propulsion system of IB Polaris is based on Azipod® propulsion and it applies a novel three propulsion unit concept. Recently, ABB conducted a study to show how an Energy Storage System (ESS) could help improve the overall power efficiency of icebreakers, saving fuel and reducing emissions. In this case study, a real ice operation data and powerplant load profile from icebreaker Polaris was used to simulate the effects of adding an ESS. The simulation indicated substantial benefits to both LNG and diesel operation. The key findings of the study will be presented in this paper.
Detection and Assessment of Asphaltene Precipitation/Deposition at Reservoir Conditions and Gas Hydrate Formation in the Presence of Thermodynamic Hydrate Inhibitors
Authors: Delgado-Linares Jose G. , Wang Weiping , Ayyad Wedyan , Majid Ahmad A. A. , Pohl Mathias , Yoda Chitose , Tanaka Norio , Zerpa Luis E. , Prasad Manika , Koh Carolyn A. 
Published: April 2023

Abstract
The occurrence of asphaltenes and gas hydrates represents a serious flow assurance problem faced by engineers at different stages of oil production. Early detection and evaluation of the impact of these solids on the hydrocarbon flowability is key in reducing the OPEX for remediation treatments. The access to reliable experimental data on asphaltene and gas hydrate formation and mitigation at reservoir/field conditions represents a valuable tool to improve the accuracy of existing prediction models / software packages and make them applicable for new scenarios faced by the industry. In this work, asphaltene precipitation/deposition and redissolution in a core was detected by using in-situ acoustic measurements at ambient and high CO2 pressures. Acoustic velocity increased during asphaltene deposition, indicating a cementing effect in the sample pores. In contrast, asphaltene redissolution with toluene induced a reduction in velocity of the acoustic wave travelling through the sample.
Rheological properties, such as viscosity and yield stress, were measured for hydrate slurries in crude oil for under-inhibited systems with two different thermodynamic hydrate inhibitors (THI): methanol (10 vol.%) and monoethylene glycol (10 vol.%). The addition of these thermodynamic hydrate inhibitors reduced the amount of formed hydrates with respect to the untreated system, and thus the viscosity and yield stress were also reduced.
Pipeline Fatigue Damage Monitoring During Hydrogen Transportation
Authors: Bhowmik Subrata , Sun Ta Ju 
Published: April 2023

Abstract
Real-time monitoring of the existing natural gas infrastructure using multiple sensors is crucial to achieving higher confidence and lower risk during hydrogen transportation. One of the main challenges during hydrogen transportation is that hydrogen can accelerate the pipe material's fatigue crack growth rate, which can be affected by operational variables like hydrogen gas pressure, load ratio, and load cycle frequency. The proposed solution will involve the development of a digital twin framework incorporating a data-driven fatigue crack model of existing natural gas pipelines. The digital twin system comprises three main components. A computational finite element-based model of the crack defect in the pipe is developed to calculate the stress intensity factor (SIF) for different crack lengths and depths. The computation model is used to estimate the fatigue damage. The input and output data from the computational model are used to develop a metamodel or surrogate model. The metamodel is a data-driven model typically used to replace the computational FE model in real-time fatigue damage monitoring or to estimate the remaining fatigue life. The data-driven and computational model outputs the fatigue damage or remaining fatigue life, which is an essential part of the decision-making process in the digital twin framework.
Machine learning-based algorithms: Extreme Gradient Boosting (XGBoost) is used to estimate the SIF through a surrogate model. The result from surrogate model is compared with the Physics-based/ simulation model. This work uses Paris's law in the crack propagation model to calculate the fatigue crack's growth rate. Conventional S-N curve methods can only provide information about fatigue life, which typically corresponds to the point of fatigue damage initiation. In a digital twin system, the crack model predicts the crack growth or damage propagation which is a substantial advantage for real-time pipeline integrity management during hydrogen transportation.
The proposed concept will provide a predictive early identification methodology for possible hazardous conditions specific to natural gas pipelines for hydrogen transportation.
Vito FPS: Designing a Simple, Light-Weight, Single Lift Topsides
Authors: Cabrera Jonathan Evan , Bradford Graham Patrick , Lewthwaite Ralph Stephen 
Published: April 2023

Abstract
This paper provides an overview of the design of the Vito topsides production train and the overall approach to achieve a minimum technical scope, a simplistic design, and limit the payload to 10,000 st. A 10,000 st topsides target was utilized in order to fabricate a single topsides module and integrate the deck with the hull in a single lift, which were key enablers to maximize flexibility and efficiency in construction and commissioning. Efforts to design the topsides production train included focusing on an integrated approach with the wells and flow assurance teams to optimize the end-to-end design and enable the elimination of unnecessary topsides equipment, thereby reducing the total topsides footprint and weight. The topsides design focused on an "industry solution," by partnering with industry firms to evaluate the minimal equipment required to meet the nameplate capacity of 100,000 bopd. Redundant equipment, whose function could be accommodated via other equipment, was eliminated and the production train was optimized as an overall system, rather than focusing on individual equipment design.
Key challenges included reducing the overall weight of the original Vito concept by 75% through rigorous evaluations of what the "minimal scope" should include. This was achieved through setting aggressive targets, actively managing design and scope growth to meet the targeted lift weight, designing and operating a facility that "looks different," balancing expected availability of the facility with weight and cost trade-offs, limiting future expandability, and reducing Personnel Onboard (POB).
The end result was a radical redesign of the Vito Floating Production System (FPS) with simplified equipment and systems designed against minimum technical specifications, resulting in a weight reduction of the host by ~75% allowing for a much more efficient use of Company's CAPEX (Capital Expenditure) and an industry competitive FPS (Floating Production System).
This paper is part of a Vito Project series at OTC 2023, and the other papers are listed in the references.
The Importance of Secondary Traps and Sinks in Offshore CO2 Sequestration
Authors: Coffin Richard , Vasilyeva Maria , Pecher Ingo , McConnell Dan 
Published: April 2023

Abstract
Geologic carbon sequestration currently focuses on injection of supercritical CO2 into reservoirs, often in a depleted hydrocarbon field. Seal integrity above these reservoirs is therefore critical for safe long-term storage of CO2. It is generally assumed that if a reservoir was able to contain hydrocarbons for millions of years, it should be suitable for CO2 storage. However, many hydrocarbon reservoirs leak, probably best documented by the ubiquitous natural gas and oil seeps observed e.g., in the Gulf of Mexico. With integration of seismic and geochemical data and fate-transport modeling there is capability to select efficient storage locations in the deep coastal sediment and provide accurate assessment of CO2 residence time.
We propose that even if reservoirs leak CO2, abiotic and biogeochemical reactions from the injection point to the ocean floor surface provide diverse traps that result in efficient sediment CO2 sequestration. First, during the migration concentration in porewater becoming supersaturated can result in a carbonate formation. This carbonate formation may cause a trap and with the CO2 build up there can be pressurization that results in horizontal migration to a new vertical path or pressurization that results in fractures of carbonate or clay layers. This transport can occur at multiple intervals during migration to the surface sediment and this step-by-step trapping slows down long-term vertical migration.
Johan Sverdrup: The Final Lap of a True North Sea Giant
Authors: Lossius Vibeke , Nedrelid Tone 
Published: April 2023

Abstract
The second phase of Johan Sverdrup came on stream in December 2022. This paper focuses on the execution of Johan Sverdrup phase 2 and describes the assessments and investments for improved oil recovery (IOR) from one of the largest oil fields in Norway.
The Johan Sverdrup field development has been called Equinor's ‘digital flagship’, and this paper includes the proof of concept for the digital initiatives after more than three years of operation.
Despite the Covid-19 pandemic Johan Sverdrup phase 2 has been able to deliver on schedule, under budget, and with an excellent safety record. The paper includes experiences from the concept development and engineering phase to the global contracting strategy, through the construction on multiple building sites in Norway and globally, and until the end of the completion phase offshore Norway.
Johan Sverdrup is the third largest oil field on the Norwegian Continental Shelf (NCS), and with recoverable reserves estimated at 2.7 billion barrels of oil equivalents, has the resources to be a North Sea Giant. Start-up of the Johan Sverdrup phase 2 extends and accelerates oil and gas production from the NCS for another five decades. This paper aims to highlight what it took to make Johan Sverdrup a true North Sea Giant, fit for the 21st century: a safe and successful execution of a mega-project, with next-generation facilities adapted to a more digital way of working, with an ambition to profitably recover more than 70% of the resources, while limiting carbon emissions from production to a minimum. In many ways the Johan Sverdrup development has set a new standard for project execution in Equinor.
The impact of different variables made during the execution of the project, such as the Covid-19 pandemic, market effects, procurement strategies, value improvement initiatives, execution performance and reservoir characteristics is addressed, as well as describing assessments and investments for improved oil recovery (IOR). Data acquisition, Permanent Reservoir Monitoring (PRM), fibre-optic monitoring of wells, innovative technologies, and digitalization, as well as new ways of working are included. Equinor´s digital strategy was established in 2017, and Johan Sverdrup was highlighted as a digital flagship at that time and a frontrunner in applying digital solutions to improve safety and efficiency from the development to the operational phase. What has been implemented so far together with experiences will be shared.
Selection of An Optimum CO2 Dehydration Technology: A Case Study Comparing Absorption and Adsorption Technologies
Authors: Müller Dieter , Greene Margaret , Pan Justin , Thompson Kirstie , Deshmukh Salim , Grison Arnaud 
Published: April 2023

Abstract
Carbon capture and storage (CCS) projects are increasingly being announced as companies strive to reach new sustainability targets. The dehydration of CO2 streams from carbon capture is a critical step to ensure safe and effective CO2 transport and storage. The most common dehydration methods are Triethylene Glycol (TEG) absorption and solid material adsorption. Silica gel, activated alumina, and molecular sieves are different types of adsorbent materials that can be used for gas dehydration. In this paper, the authors present a case study requiring a &lt;100 ppmv H2O outlet specification and evaluate the technologies on capital and operational costs.
There are factors beyond treated gas water specification to consider when choosing the ideal dehydration solution, including treated gas glycol specification, plot space, module weight, maintenance intensity, energy duty, and start-up time. When these factors are considered, aluminosilicate gel adsorption technology has benefits over TEG. No one factor can be used to make the decision on which dehydration solution is best; those factors holding more weight depend on the specifics of a given project.
Arctic Field Testing – Developing the Next Generation Passive Fire Protection
Authors: Skilbred Anders W. B. , Wierzba Zuzanna , Irving James 
Published: April 2023

Abstract
Epoxy passive fire protection (PFP) products are extensively used for fire proofing of structures and assets around the world. Significant projects such as construction of large hydrocarbon processing industry (HPI) plants may require a global supply chain meaning that a structure or an assembly may be manufactured one location and assembled in another. Manufacturing, application of coatings, handling, transportation, and construction will for many large projects take place in different climates. It is therefore important that an epoxy PFP product shows excellent cold climate properties for all climate performance.
This study presents mechanical properties of one newly developed and three commercially available epoxy PFP products. The flexural strain of the newly developed epoxy PFP was found to be similar or higher than the other tested products for temperatures between −50 °C and 20 °C. Further, the strength at break, i.e. at the point of fracture, of the tested epoxy PFP products was found to increase as a function of decreasing temperature. Leading to the conclusion that the newly developed epoxy PFP was more robust at especially at lower temperatures, compared to the commercially available products.
An Arctic test station located outside Longyearbyen at Svalbard in Norway was used for outdoor cold climate exposure After approximately one year, it was found that a low flexibility product showed significant cracking, whereas the more robust newly developed epoxy PFP showed no visual degradation.
Thermal Insight - Digital Twin Technology for Enhancing Asset Uptime and System Reliability
Authors: Målbakken Kristian , Sundell Emma , Martinsson Andreas , Vullum-Bruer Kenneth 
Published: April 2023

Abstract
Thermal Insight, visualized in Figure 1, establishes a new frontier for operators to increase reliability and uptime of SPS systems by avoiding cold restarts. The Digital Twin is a live diagnosis tool that provides critical information about the actual cool down time of critical locations in the Subsea Production System (SPS), in the event of an unplanned shut down.
Based on verified Computational Fluid Dynamics (CFD) tools, Thermal Insight adopts a holistic full field view and feeds back the actual cool down time in predetermined stringent locations to the operator. This facilitates well informed decision making, opposed to immediate shut down and cold restart following conservative cool down requirements and philosophies.
The inner workings of the Digital Twin are a Reduced Order Model (ROM) set of differential equations based on a-priori CFD simulations which reveals the cool down time in critical locations, and not only in the location of installed hardware (PTT sensors). The CFD results are used to correlate the real time temperature readings from the Pressure/Temperature Transducer (PTT) to cool down times in the most stringent parts of the SPS, limiting the number of cold restarts to when it is really needed.
This paper will outline the CFD model verification work along with the Digital Twin deployed onto an example scenario based on actual field data from an operator.