bluuebunny/crossref_metadata_2025_split huggingface dataset:
Working Load in a Container Stack Nonlinearity With Twist Lock Separation
Authors: Yanagimoto Fuminori , Ishibashi Kinya 
Published: September 2023

Abstract
Safe and high-efficient marine transportation needs accurate estimation of forces acting on each part of containers and related devices used for container securing system. Recent employment of the fully-automatic twist lock causes nonlinear behavior of force transmission in a container stack. This study is composed of two parts; first, a series of nonlinear 2D finite element analyses were carried out to investigate how the nonlinearity in the twist lock contributed to the force acting on the container and related devices. Second, a simplified model was developed to simulate the force based on the observation of above finite element analyses. The finite element analyses showed that the twist lock separation enhanced the contribution of the lashing rod to the strength of a container securing system, especially in the external lashing cases. The simple model was developed based on the finite element analyses. The nonlinearity was solved using the bisection method, and three conditions of the twist lock was employed to judge the convergence. The model successfully estimated the acting force in sufficiently small error compared to the finite element analyses.
Comparison of Ocean Wave Direction Spectra Estimated Using an Array of Three Optech Laser Sensors and a Directional Waverider Buoy
Authors: Jangir Pramod Kumar , Ewans Kevin C. , Young Ian R. 
Published: September 2023

Abstract
Accurate measurement of the directional properties of waves is needed for a variety of applications, including the safe and economical operation of offshore and shipping industries, climate monitoring, air-sea interaction, and sediment transport. Recent studies have indicated differences in significant wave heights (Hm0) estimated from Eulerian and Lagrangian measurement types of approximately 10%. Similar differences might be expected in measurements of directional properties due to the different measurement principles. Spatial arrays of wave sensors and Directional Waverider (pitch/roll) buoys are commonly used to measure direction wave spectra. This paper compares directional spectra estimated from wave measurements made with a spatial array of three Optech Lasers and a Directional Waverider Buoy operating at North Rankin A platform located on the northwest coast of Australia, using the maximum likelihood method (MLM). This comparison reveals the following: (a) the mean wave directions from the spatial array and the Waverider differ by up to approximately 20°; (b) the Waverider directional spreading at the spectra peak is narrower compared to the spatial array; however, (c) at frequencies above 1.3 times the peak frequency (f = 1.3fp), the directional spreading from the Laser array is narrower compared to the Waverider. (d) The directional spreading estimates of the Waverider at the spectral peak is a weak function of inverse wave age (U10CP), particularly at higher sea states; however, the Laser array measurements do not show such a dependence.
Pitch Motion Control of Spar-Type Floating Wind Turbines
Authors: Yu Shuang-Rui , Zhang Ming , Chen Ming-Lu , Yuan Zhi-Ming 
Published: September 2023

Abstract
Wave-induced pitch motion has adverse effects on the power generation of Floating Wind Turbines (FWTs). The traditional blade-pitch system, which is commonly used for regulating wind energy capture and power generation, can also be utilized to reduce the platform pitch motion. However, frequent active blade pitching can harm the wind turbine’s blade-pitch bearing and gear system, leading to inevitable deficiencies in controlling such wave-induced pitch motion. Many structural control methods have been proposed to mitigate the motion of floating substructures. The present study proposes an active structural control method utilizing a plate hinged at the bottom of a spar-type floating substructure as an external control device. The damping force provided by the hydraulic Power Take Off (PTO) system between the spar and the plate serves as the control force during optimization. The controller is developed under an optimal declutching control framework, in which the damping coefficient of the PTO system is set as a binary function. It is found that current optimal declutching control strategy can effectively minimize the pitch motion of the spar-type substructure and maximize the PTO’s power simultaneously. This indicates that more mechanical energy of the spar has been converted into electric energy. The proposed controller is able to reduce the wave-induced pitch motion by more than 21% and increase the PTO power capture by more than 370% at the platform’s natural frequency than without control.
Hydrodynamic Damping of an In-Line Oscillating Cylinder In-Line in Steady Flow
Authors: Ren Chengjiao , Cheng Liang , Tong Feifei 
Published: September 2023

Abstract
This study conducts a series of analysis to reconstruct the time-dependent in-line forces on an in-line oscillating cylinder in steady flow. The analysis involves reconstructing these forces from several approaches and comparing them with those obtained from the three-dimensional numerical simulations conducted at a fixed Reynolds number of 500 based on the incoming steady flow velocity. A range of velocity ratio r* (cylinder-oscillation-velocity to current velocity) from 0.1 to 1.83 at amplitude-to-diameter ratio A* = 1/π are considered. To quantify their performance, the reconstructed in-line force and damping force from the conventional Morison Equation (MOJS) with the relative and independent velocity models are examined. The results show that the independent velocity model outperforms the relative velocity model and provides a good fit at large r* where the wake is controlled by the cylinder oscillation. The study also demonstrates that the independent velocity model using a more general form of MOJS is superior to the conventional formula in predicting the in-line force. Recommendations are provided on selecting velocity models in force estimation at different r* ranges.
Methodology for Selection of Co-Simulation Platform for Digital Twin Development of Maritime Energy Systems
Authors: Gosala Vaidehi , Hachmeister Ludger , Stutz Sophie , Giering Jan-Erik , Ehlers Sören 
Published: September 2023

Abstract
Digital twins (DTs) are being increasingly considered in the maritime industry for the purposes of system design, monitoring, control, optimization, operational planning, maintenance, fault detection, and life cycle management. A system simulation can be utilized to enable many of these functionalities. Co-simulation based on the Functional Mock-up Interface (FMI) is typically used to interface component models independently developed in different modelling platforms, possibly having different supplier intellectual property restrictions. Currently, more than 170 software tools support FMI, a subset of which also support co-simulation. In this paper, a methodology for the selection of a co-simulation platform for a maritime DT is presented. The methodology is demonstrated for two maritime energy system case studies with different DT purposes and users, that represent different phases of a ship’s lifecycle. MATLAB/Simulink and Open Simulation Platform (OSP) are used as example co-simulation platforms. The DT’s purpose and its users are considered to understand the functional and interface requirements for a qualitative comparison of the platforms. Additionally, the platforms’ performance is compared quantitatively by co-simulating Functional Mock-up Units (FMUs) of the component models. The derived requirements, as well as the platforms’ capabilities and offerings, are then analyzed to select a suitable platform. It is shown that the choice of the co-simulation platform can be different according to the DT’s purpose, users, and phase of the ship’s and DT’s lifecycle.
Miniaturised Testing Device for the Qualitative Analysis of Gas Exsolution in Soil
Authors: Kaminski Pauline , Grabe Jürgen , Fatima Zeest 
Published: September 2023

Abstract
The presence of gas is a widespread phenomenon in marine and coastal soils, often accompanied by complications in engineering application. The characteristics of the gas phase in the pore space are relevant for the assessment of the soil mechanical implications. In granular soils the formation of capillary bridges between the soil particles can invoke cohesive forces. In fine-grained soils gas-induced fractures may weaken the soil structure. Additionally, an excessive gas production leads to a build-up of pore pressures and can thereby trigger a liquefaction failure in granular soils. To enable a differentiated investigation of these features, however, it is vital to look into the inner pore space of a gassy soil. For this purpose, a miniaturised experimental set-up was developed which allows for the documentation of gas bubble nucleation and growth in a soil’s pore space by means of the imaging technique X-ray computed tomography. Herein, gassy soil samples with a stationary grain structure are obtained by means of the axis-translation technique. The degree of saturation is adjusted by a controlled pressure relief. During image processing the three phases — soil particles, pore water and gas — are identified and thus, their interaction can be studied. The microscopic insights gained with the help of this experimental set-up will allow validation or falsification of the basic theoretical assumptions on gassy soils. Furthermore, the data bears great potential for the advancement of approaches for multiphase simulation.
Cuttings Bed Creation and Removal When Circulating Field Applied Oil-Based Drilling Fluids
Authors: Ytrehus Jan David , Lund Bjørnar , Taghipour Ali , Saasen Arild 
Published: September 2023

Abstract
Deviated well sections are common in modern well construction. In mature areas like the North Sea region, practically all producers or injector wells will have highly deviated sections. These wells must be drilled and completed in an optimal manner with respect to drill time, cost, risk and functionality. Most cuttings transport and hydraulic models are developed based on tests with model fluids and often in small diameter test sections. Hole cleaning and hydraulics with field fluids are different than the properties considered with most model fluids. Furthermore, results from small diameter tests with model fluids may not always be relevant for, nor scalable to, field applications due to time, length and other scales. Hence, there is a need for studies in controlled laboratory environments with various field application designed drilling fluids to improve engineering models and practices.
This paper presents results from laboratory studies with geometries that permits comparison with field operations when oil-based drilling fluids from Norwegian offshore operations are applied. The oil-based drilling fluids have densities and viscosities within the relevant shear rate range applied during drilling operations and in the tests. Previously published results with realistic fluids from this setup are with steady state conditions. Here characteristic transient behavior is presented and discussed.
The experiments have been performed in a flow loop that consists of a 10 meters long test section with 2” OD freely rotating steel drill string inside a 4” ID wellbore made of cement. Sand particles were injected while circulating the drilling fluids through the test section. Experiments were performed at different wellbore inclinations. The applied flow loop dimensions are designed so that the results are scalable to field applications; especially for the 12,25” and 8,5” sections. The selected setup is designed to provide correct shear rate ranges and equal Reynolds number to the field application when the same fluids are applied.
Results show that bed creation can be described as an alpha wave together with a bed thickness growth from start of drilling a highly deviated well section. The bed removal characteristics in presence of increased flow rate and/or increased drill string rotation are described.
Electrification of the Coastal Fishing Fleet Using Hydrogen and Ammonia-Fed Fuel Cells
Authors: Jafarzadeh Sepideh , Ladstein Jarle , Ødegård Anders , Sundseth Kyrre , Muñoz Ortiz Miguel , Høyli Randulf , Zenith Federico 
Published: September 2023

Abstract
In 2021, the Norwegian fishing fleet emitted approximately 855 000 tonnes of carbon dioxide-equivalents, which accounts for 1.3% of the total emissions in Norway. Converting to zero and low emission fuels is one of the measures that can significantly reduce GHG emissions of the fishing fleet. This study investigates the possibilities for using hydrogen and ammonia-fed fuel cells for powering a coastal fishing vessel (a 13 m longliner). The study is part of a Norwegian project where several stakeholders and research and industrial entities collaborated. General arrangements for the vessel are sketched for various trip lengths and configurations of power system using hydrogen, ammonia, batteries, and diesel. The effect of using alternative fuels on dimensions, specifications and stability are evaluated. Safety aspects for the vessel and bunkering are assessed. Using mathematical optimisation, the economic aspects of using alternative fuels onboard the vessel are studied. Finally, the environmental aspects of adopting alternative fuels on similar vessels and requirements for the infrastructure in ports are discussed. The results show that ammonia has the highest potential for reducing emissions for long trips; however, there are technical, economic and safety challenges with using ammonia. It is concluded that hydrogen-driven fishing vessels are feasible, but the Norwegian fish quota system, which among other aspects is based on vessel length, creates limitations for fuel storage and thus longer ranges.
Investigation on Residual Contact Pressure of Mechanically Lined Pipe With Partially Plastified Carrier Pipe Based on Tresca Criterion
Authors: Wei Rongzhi , Vaz Murilo Augusto , Hu Xuefeng , Guo Jianing 
Published: September 2023

Abstract
Mechanically Lined Pipe (MLP) refers to a bi-metal composite structure that consists of a carbon steel pipe internally lined with a thin coating of a Corrosion Resistance Alloy (CRA) to protect it against caustic substances from the internally transported fluid. Mechanical expansion is the most typically employed fabrication method. A major challenge for the installation and operation of MLP is the liner wrinkling caused by repeated bending during reeling installation and excessive axial compression due to thermal loads. Improving the interlayer gripping force is the key to avoiding wrinkling. The traditional fabrication process requires maintaining the outer carrier pipe completely elastic for production controllability. However, a moderate amount of plastification of the carrier pipe can further enhance the interlayer mechanical adhesion. The stress and strain analysis based on the Tresca criterion is performed for the hydraulic loading (expansion) and unloading process as a prelude to deriving the hoop strain compatibility equation. Both the models with nonhardening and linear-hardening carrier pipes partially plastified, and the closed-end solution to residual contact pressures are developed and compared. The results demonstrate that proper plastification of the linear-hardening carrier pipe is beneficial for increasing the residual contact pressure, namely, the MLP’s resistance to wrinkling.
Implementation of Industry 4.0 and its Effect on Human Element and Sustainable Development in the Blue Economy
Authors: Emad Gholam Reza , Shahbakhsh Mehrangiz , Abdussamie Nagi , Islam T. M. Rabiul 
Published: September 2023

Abstract
Industry 4.0 is revolutionising all industries including Blue Economy, and transforming different aspects of the way we live, work, and learn. Industry 4.0 has redefined entire services and processes through intelligent and integrated technologies such as Cyber-Physical-Systems (CPS), the Internet of Things (IoT), and artificial intelligence (AI). The Industry 4.0 has brought many positive changes and at the same time challenges that directly or indirectly involve the human element and sustainability. While the long-term strategy of the Blue Economy is aimed at unlocking the potential of ocean resources, a qualified and intelligent workforce in a sustainable environment can increase productivity and growth opportunities. So far, Industry 4.0 application in the Blue Economy industry has mainly addressed technological innovation. However, so far, the future role of the human and sustainability were not the focus of the R&D activities and thus under-researched. Understanding such a role is important, as industry 4.0, through digitalisation and automation, is redefining jobs, work activities, and the workplace itself. This entails not only the need for training a new breed of workforce who are able to operate novel systems but also affects the design of support equipment and systems for the offshore environment. This paper aims to explore the current status of human elements and sustainability associated with the application of Industry 4.0 on the Blue Economy programs such as aquaculture and renewable energy industries by utilising a systematic literature review. The paper will focus on issues that include changing the nature of jobs and its effect on the workforce in the Blue Economy industries and the need for training and upskilling of the workforce.
Experimental Study on the Hydrodynamic Performance of a U-Shaped Flexible Membrane Breakwater
Authors: Wu Jingping , Yi Xi , Zou Zaojian , Zhan Peng , Chen Changzhe 
Published: September 2023

Abstract
A new U-shaped flexible membrane breakwater is proposed, and its hydrodynamic performance of wave attenuation is experimentally studied in a physical wave flume with piston-type wavemaker. The physical breakwater model is consisted of two U-shaped flexible membranes and four slats. The four slats are stuck to the four ends of the two membranes and fixed near the free surface, and the flexible membranes are extended freely down and form the U-shaped inner and outer layers, with the bottom of the outer membrane lying flat on the flume bottom. The effects of the submerged or immerged depths of the four slats are studied; and a single membrane breakwater is compared with the two-membranes breakwater. A series of monochromatic regular waves are generated at a constant water depth and propagate normally to the breakwater models. The wave elevations on both the windward side and leeward side are recorded by the fixed wave probes respectively. The hydrodynamic performances including transmission coefficient, reflection coefficient and energy dissipation coefficient are calculated, and the variations of the three coefficients versus the relative width are presented. The results demonstrate that the two-membranes breakwater is obviously better than the single membrane breakwater; the slats positions have slight influence on the wave attenuation performances. Overall, the U-shaped flexible membrane breakwater shows a high performance of attenuating wave even for the waves with relatively long wavelength by dissipating the wave energy.
Study on Influencing Factors of Deep-Water Shallow Gas Jet Height via Numerical Simulation
Authors: Long Yang , Yang Jin , Yin Qishuai , Li Li , Xue Qianling 
Published: September 2023

Abstract
Actively releasing shallow gas operation is a drilling operation mode to release shallow gas from underground zone in advance, which is benefit in guaranteeing the security of the subsequent drilling operation. The shallow gas jet height is a key indicator to determine the safety of actively releasing shallow gas operation. The main influencing factors of shallow gas jet height include shallow gas reservoir pressure coefficient, pilot hole size, water depth and shallow gas reservoir buried depth. The increase of shallow gas reservoir pressure coefficient will stimulate higher jet height, while a certain degree of increase of water depth, shallow gas reservoir buried depth and pilot hole size will reduce the jet height of shallow gas, and the existence of sea current will accelerate the collapse and diffusion of shallow gas bubbles. The study of variation law of shallow gas jet height with each influencing factor is systematically carried out via numerical simulation, and the calculation results provide reference to predict the shallow gas jet height under corresponding parameters, which provides theoretical support and guiding significance for the decision of actively releasing shallow gas by pilot hole in deep-water sea.
Strength Assessment Methods for Adhesively Bonded Repair
Authors: Paboeuf Stéphane , Deydier Maxime , Sourisseau Quentin , Quéméré Marie-Odette , Court Jean-Philippe , Paillusseau Christophe 
Published: September 2023

Abstract
Bonding is an attractive assembly solution in many ways. Indeed, it is a non-intrusive and cold solution enables to assemble mono or multi-material structures. This assembly technique is particularly interesting for the installation of equipment or repairs when welding is prohibited, such as in ATEX-type risk areas.
For many years, COLD PAD has been developing bonded structural repair solutions and non-intrusive mechanical fasteners for marine environment. Their reinforcement product ColdShield™ [1], has been validated thanks to a previous collaboration with Bureau Veritas. From his side, Bureau Veritas is updating the guidance Note NI613 Adhesive Joints and Patch Repairs [2] to consider new development and innovation achieved in this technical domain.
The objective of this paper is initially to present the different methods for evaluating the resistance of bonded assemblies proposed by Bureau Veritas. Two application cases of bonded repair will be detailed with the associated lessons learnt in terms of reliability. The first one concerns a conventional steel-steel bonded repair, one of studied applications within the framework of the JIP Strength Bond Offshore [3]. For this application, the stress approach and the combined stress-energy method will be explained as well as the use of cohesive elements for numerical simulations. The second one is the design assessment of the ColdShield™ reinforcement solution [4], which contributes to hull girder strength for Floating Production Storage and Offloading (FPSO) hull repair, and for which a stress approach is possible due to the specificity of the design. Results of both applications are analysed, compared and commented. In conclusion, the paper will highlight the importance of the calculation methodology and its robustness to avoid a misinterpretation of the strength.
A Hybrid Numerical Framework for Engineering Design of Floating Offshore Wind Turbine Foundations
Authors: Tomaselli Pietro D. , Mandviwalla Xerxes , Jensen Bjarne 
Published: September 2023

Abstract
In addition to physical model tests, designers rely on numerical models to investigate the complex response of Floating Offshore Wind Turbine (FOWT) foundations to environmental conditions at sea. This paper presents a hybrid numerical framework for predicting the wave-induced motions of FOWT foundations. The framework combines the capabilities of three models, a wave propagation model, a potential flow solver, and a CFD solver. The developed framework can flexibly support different stages of the design process, from fast response assessment under several wave climates to detailed analyses in operational scenarios and extreme wave events. Wave and foundation response modelled with the framework are compared against laboratory measurements. Results are discussed and areas of improvement are identified.