Applied Ocean Research最新文献

{"title":"Experimental study on shock wave and bubble pulsation behavior generated by underwater aluminum wire electrical explosion","authors":"Yang Gao ,&nbsp;Tonghui Yang ,&nbsp;Cheng Wang ,&nbsp;Yuanbo Sun","doi":"10.1016/j.apor.2024.104407","DOIUrl":"10.1016/j.apor.2024.104407","url":null,"abstract":"<div><div>Underwater electrical wire explosion (UEWE) is an efficient source of underwater shock waves and bubble pulsation. However, the impact of wire parameters on the dynamics of shock waves and bubbles generated by UEWE has not been thoroughly explored. In this paper, we present novel insights based on a self-built UEWE experimental platform, where high-power electric pulses are used to ionize and explode aluminum wires of varying diameters and lengths in water. The experimental investigation focused on the resulting shock waves and bubble pulsation behavior, contributing to a deeper understanding of the mechanisms underlying these phenomena. First, we examined the energy storage conditions of the pulse capacitor and characterized the discharge behavior of the electrical explosion. Subsequently, we analyzed the bubble generation mechanism and the complete pulsation process, comparing the maximum bubble radius with the Rayleigh-Plesset equation solution, finding a high degree of consistency during the first pulsation period. Furthermore, we explored the relationships between the maximum bubble radius, shock wave energy, bubble energy, shock wave pressure, pulsation pressure curves, and bubble pulsation period under various experimental conditions. Our results demonstrate that for a 0.5 mm diameter aluminum wire, both the shock wave energy and bubble energy are positively correlated with the wire length, achieving maximum efficiencies of 13.04 % and 79.7 %, respectively. The shock wave peak under each experimental condition also shows a positive correlation with wire diameter and length, while the second pressure wave exhibits a concave trend and the third a convex trend. Notably, before the bubble pulsation period reaches its peak, the period shortens as the wire diameter and length increase, influenced by the aluminum-water reaction. These findings provide a novel perspective on UEWE, advancing the research of explosion bubbles to ensure safer and more efficient underwater explosions, thereby contributing to the broader field of underwater explosion mechanics.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"154 ","pages":"Article 104407"},"PeriodicalIF":4.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166949","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of an acoustic sensor to monitor synthetic mooring lines","authors":"Martin Träsch ,&nbsp;Peter Davies ,&nbsp;Damien Le Vour’ch ,&nbsp;Vincent Perier ,&nbsp;Michel Répécaud ,&nbsp;Guillaume Damblans ,&nbsp;Romain Ribault ,&nbsp;Jean Sebastien Verjut","doi":"10.1016/j.apor.2024.104398","DOIUrl":"10.1016/j.apor.2024.104398","url":null,"abstract":"<div><div>Fiber ropes (polyester, nylon, HMPE, etc.) are being considered for Floating Offshore Wind Turbines mooring lines, as they can reduce mooring weight and cost. Measuring the strain of these synthetic mooring lines could help to understand their behavior and long term monitoring of these systems could lead to their design and maintenance optimization.</div><div>A new strain sensor for synthetic mooring lines is proposed in this paper. It uses an ultrasonic altimeter to measure the distance between the transducer and a target fixed on a synthetic mooring line. This instrument is non-intrusive and can be fixed on anchor lines after their installation at sea. The measurement principle and prototype design are presented. Then, the validation of the concept in a water tank is described, demonstrating the feasibility of measuring length using acoustic waves with a high degree of accuracy. The acoustic strain sensor was deployed in operational condition on a demonstrator buoy mooring line in the Mediterranean sea, together with a wire displacement sensor and a load sensor. The measurements from these three instruments are compared, showing the ability of the acoustic sensor to monitor the behavior of a mooring line at sea.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"154 ","pages":"Article 104398"},"PeriodicalIF":4.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of backfilling stiffness and configuration on seabed failure mechanisms and pipeline response to ice gouging","authors":"Alireza Ghorbanzadeh,&nbsp;Hodjat Shiri,&nbsp;Xiaoyu Dong","doi":"10.1016/j.apor.2025.104413","DOIUrl":"10.1016/j.apor.2025.104413","url":null,"abstract":"<div><div>Ice gouging is a significant issue for offshore structures in cold environments. Pipelines in Arctic regions are buried in the seabed to prevent the direct contact of pipelines and the impacts of soil displacement from ice gouging. However, choosing the appropriate backfilling material and stiffness to maintain the pipeline's integrity while minimizing construction costs is a complex design consideration. It is crucial to accurately model the interaction between the ice, backfill, trench wall, and pipeline to assess the backfill functionality in a coupled ice gouging analysis. This study comprehensively investigated the effect of backfilling stiffness and configuration on seabed failure mechanisms and pipeline response during ice gouging events on a deeply buried pipeline. The study focused on six different backfill materials, including dense and loose sands and very soft clay to stiff clay. The Coupled Eulerian-Lagrangian (CEL) method was used to simulate the large seabed deformation due to the ice gouging process in a trenched/backfilled seabed in Abaqus/Explicit. Incorporation of the strain-rate dependency and strain-softening effects involved the development of a user-defined subroutine and incremental update of the undrained shear strength within the Abaqus software. Key findings reveal that both overly soft and excessively stiff backfill materials can negatively impact pipeline response during ice gouging. Very soft clay exhibits a distinct \"removal\" mechanism, leading to increased pipeline displacement, while overly stiff clay and dense sands result in more significant displacement due to efficient force transfer. The results can inform the selection of appropriate backfill materials and backfilling techniques to enhance pipeline protection against ice gouging.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"154 ","pages":"Article 104413"},"PeriodicalIF":4.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multi-Target Tracking for Autonomous Surface Vessels Using LiDAR and AIS Data Integration","authors":"Andreas von Brandis ,&nbsp;Daniel Menges ,&nbsp;Adil Rasheed","doi":"10.1016/j.apor.2024.104348","DOIUrl":"10.1016/j.apor.2024.104348","url":null,"abstract":"<div><div>Autonomous Surface Vessels (ASVs) rely on advanced perception algorithms to accurately represent internal and external conditions. One of the most challenging tasks is tracking surrounding objects, especially in the presence of model and measurement uncertainties. In case of multiple dynamic obstacles, the tracking problem becomes highly important to guarantee safe navigation. Therefore, we propose a multi-target tracking algorithm based on Light Detection And Ranging (LiDAR) and Automatic Identification System (AIS) data. To estimate the shape of other vessels, a Numerically Stable Direct Least-Squares (NSDLS) ellipse fitting algorithm is applied to LiDAR point clouds. For that purpose, the point clouds are separated into clusters using a modified version of Density-Based Spatial Clustering of Applications with Noise (DBSCAN). To improve the robustness of the tracking algorithm, the LiDAR-generated estimations are fused with AIS measurements using a Kalman Filter (KF). The motion model used for the KF enables the prediction of dynamic obstacles surrounding the ASV. This proactive awareness can be used for predictive control concepts such as Model Predictive Control. However, testing such advanced algorithms on real systems can be dangerous. A Digital Twin (DT) allows for an extendable integration of physics-based models, sensor data, and intelligent algorithms, enabling simulations in a safe environment. This work demonstrates the proposed multi-target tracking approach in a DT of an ASV, which contains vessel dynamics, sensor models, and real-world AIS data streams.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"154 ","pages":"Article 104348"},"PeriodicalIF":4.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanical performance after service of hybrid synthetic mooring lines for weather buoys","authors":"Peter Davies ,&nbsp;Nicolas Lacotte ,&nbsp;Gaspard Fourestier ,&nbsp;Iroise Petton","doi":"10.1016/j.apor.2024.104366","DOIUrl":"10.1016/j.apor.2024.104366","url":null,"abstract":"<div><div>Synthetic fibre ropes are increasingly popular for mooring lines of marine structures. The adoption of polyester ropes for deep water offshore platforms has resulted in a large material database, but the development of floating wind turbines has widened the scope to include more dynamic loadings and more compliant mooring lines are being developed. These are needed both for the turbines, particularly in shallow water, but also for the weather buoys which are used to obtain data on site conditions before wind park installation. This study has investigated the residual properties of weather buoy mooring lines based on hybrid fibres, polyester with polyolefin fibres. A set of lines was recovered from two shallow water sites after up to 2.5 years at sea. Significant loss of strength was measured after service, up to 50%. The reasons for this, mainly damage to external polyester fibres caused by mussel attachment, are discussed.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"154 ","pages":"Article 104366"},"PeriodicalIF":4.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143167000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the risk of fatigue failure of structural elements exposed to bottom wave slamming – Impulse response regime","authors":"Romain Hascoët,&nbsp;Nicolas Jacques","doi":"10.1016/j.apor.2024.104411","DOIUrl":"10.1016/j.apor.2024.104411","url":null,"abstract":"<div><div>This study aims to investigate whether fatigue damage induced by bottom wave slamming can be a failure mode, important to consider when sizing a marine structural element. The body exposed to wave impacts is assumed to have a shape and structural arrangement such that the duration of wave-impact loads is short relative to the structure’s vibratory response time. In this dynamical regime, fatigue is found to be a potentially important failure mechanism: accounting for the risk of failure due to fatigue damage may result in design constraints that are significantly more conservative than those based on the risk of ultimate strength exceedance. The role of fatigue damage depends on the elevation of the body. It is predominant for low elevations, for which slamming events are frequent. Since this study aims to provide general insight, the specific details of the body, such as its shape and structural arrangement, are not specified. Instead, a general framework is used for the analysis. The way forward to address a specific case study, possibly including the effects of forward and seakeeping motions, is briefly explained.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"154 ","pages":"Article 104411"},"PeriodicalIF":4.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166401","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fixed-time adaptive RBF neural network controller via minimum learning parameter for ship roll stabilization","authors":"Van Suong Nguyen ,&nbsp;Quang Duy Nguyen ,&nbsp;Tuan Son Le ,&nbsp;Hai Van Dang","doi":"10.1016/j.apor.2024.104403","DOIUrl":"10.1016/j.apor.2024.104403","url":null,"abstract":"<div><div>In this study, a fixed-time adaptive radial basis function (RBF) neural network controller is proposed for ship roll stabilization, considering fixed-time convergence, the computational burden reduction, unknown dynamics, and external disturbances. First, the fixed-time stability theory is integrated with the backstepping method to design a controller for the ship's anti-roll fin stabilizers. With this controller, the errors of the closed-loop system are ensured to converge into the origin with faster convergent time. Moreover, the settling time of the system is independent from the initial states. Second, the unknown dynamics of the ship rolling model are estimated by the RBF neural network. To reduce the computational burden of the neural control system, the minimum learning parameter (MLP) technique is incorporated into the adaptive law of the RBF neural network. Based on the Lyapunov theory, the stability of a closed-loop system is proven to be guaranteed within a fixed time. Finally, numerical simulations and comparison analyses are performed to demonstrate the effectiveness and superiority of the proposed controller.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"154 ","pages":"Article 104403"},"PeriodicalIF":4.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Computational analysis of submerged submarine bow hull dynamics subjected to torpedo blunt impact and warhead detonation events","authors":"Anand Pai ,&nbsp;Sudheendra Prabhu K. ,&nbsp;Marcos Rodriguez-Millan ,&nbsp;Chandrakant R. Kini ,&nbsp;Satish Shenoy B.","doi":"10.1016/j.apor.2024.104330","DOIUrl":"10.1016/j.apor.2024.104330","url":null,"abstract":"<div><div>In the maritime sector, ensuring the survivability of ships and submarines against diverse threats such as torpedo impacts, Underwater Explosion (UNDEX) events, and environmental factors is paramount. Comprehensive analysis of hull dynamics under various impact scenarios is essential. Numerical simulations of these impacts utilize different material models, ship grounding tests, impact modes, UNDEX simulations, and failure mechanisms. In the current study, the blunt impact of a torpedo on the submarine bow and the surface detonation effects of the torpedo warhead (at different distances from the hull) on the submarine bow structure were analyzed within an underwater enclosure. The torpedo design was based on the MK-48, with Ti<img>6Al<img>4V alloy used for the torpedo hull and HY-80 steel for the submarine hull. The impact simulations were conducted using ANSYS Explicit Dynamics® computational software. For the blunt impact scenario, a torpedo speed of 55 knots (102 km/h) was used. For the UNDEX studies, the warhead at the front end of the torpedo was modeled using PBX-9501 (a commonly used high explosive in warheads). The novelty of the current work was the employment of a water enclosure in the model to simulate the underwater impacts. The analysis focused on hull deformation, equivalent plastic and elastic strains, equivalent stress and damage profiles for the different impact scenarios. To effectively capture fluid–structure interactions, the study also examined pressure variations within the Eulerian domain. Among the scenarios analyzed, the near-field detonation of the warhead emerged as the most destructive, resulting in severe structural damage to the bow hull. In contrast, the blunt impact of the torpedo induced moderate plastic deformation, while the far-field detonation resulted in minimal damage.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"154 ","pages":"Article 104330"},"PeriodicalIF":4.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166910","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Coastal storm surge amplification by wave radiation stress: The case study of 2015 Typhoon Soudelor in East Taiwan","authors":"Yu-Lin Tsai ,&nbsp;Tso-Ren Wu ,&nbsp;Philip Li-Fan Liu ,&nbsp;Yi-Cheng Teng ,&nbsp;Hwa Chien ,&nbsp;Hao-Yuan Cheng","doi":"10.1016/j.apor.2024.104370","DOIUrl":"10.1016/j.apor.2024.104370","url":null,"abstract":"<div><div>This study investigated the coastal storm surges along the east coast of Taiwan during the passage of Typhoon Soudelor in 2015, which was a representative typhoon event making landfall from eastern Taiwan. A new coupled surge-tide-wave model was developed to simulate storm surges, tides, and wind waves from offshore to nearshore regions. The hindcast simulation was driven by the global reanalysis winds, and the input wind data and the simulation results were validated using the observations from tide gauges and marine buoys. The simulation results captured the spatial and temporal variations of storm surges, predicting the peak water levels and their arrival times accurately. Comparisons between the model simulations with and without considering waves revealed that the wave-induced radiation stresses contributed significantly to the peak surges, amplifying them by 30–50% at several tide gauge locations along the east coast of Taiwan. The intensity of radiation stress gradients was found to be 20–80 times larger than that of wind shear stresses and sea-level atmospheric pressure gradients within the surf zones at the time of Typhoon Soudelor's landfall in Taiwan. Moreover, the overall contribution of radiation stresses to storm surges was found to amplify storm tides by 23.3% to 31.5% along the east coast of Taiwan.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"154 ","pages":"Article 104370"},"PeriodicalIF":4.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166921","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hybrid data-driven long-term wave analysis in the southern Coral Sea, Australia","authors":"Mingyuan Ma ,&nbsp;Gaelle Faivre ,&nbsp;Darrell Strauss ,&nbsp;Daryl Metters ,&nbsp;Hong Zhang","doi":"10.1016/j.apor.2024.104374","DOIUrl":"10.1016/j.apor.2024.104374","url":null,"abstract":"<div><div>This paper investigates the long-term statistical characteristics of waves in the southern Coral Sea, Australia. Measured and simulated datasets from three representative sites, including both nearshore and offshore locations, were utilised. The study focuses on wave conditions with highly frequent observations and the forecast of extreme events. To address data gaps, an innovative artificial neural network model is proposed to fill in missing data points. The uncertainty in the statistical results due to seasonal variability is also assessed. The analysed results indicate that the wave climate in the southern Coral Sea shows distinct seasonal differences, but stationary stochasticity can still be applied in data analysis. For the studied sites, the lognormal distribution is suitable for describing the frequently observed wave conditions, while a GEV-GP two-part distribution model may provide an improved and flexible fitting for extreme events, albeit with wide confidence intervals. In addition, under a given recurrence period, as the significant wave height <em>H_s</em> approaches the maxima, the variation in the mean zero up-crossing wave periods <em>T_z</em> tends to concentrate within a narrow range (indicating medium-distance swell dominance), while the variation in <em>T_z</em> spans a wider range (indicating the presence of either wind waves or swells) when <em>H_s</em> is smaller. These findings enhance our understanding of wave statistics and extreme events and provide valuable insights for the design of coastal and offshore structures, as well as other research related to wave climate.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"154 ","pages":"Article 104374"},"PeriodicalIF":4.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166936","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}