Applied Ocean Research最新文献

Investigation of morphodynamic response to the storm-induced currents and waves in the Bay of Bengal 孟加拉湾风暴引起的海流和海浪的形态动力学响应研究

IF 4.3 2区工程技术

Applied Ocean Research Pub Date : 2024-11-05 DOI: 10.1016/j.apor.2024.104285

{"title":"Investigation of morphodynamic response to the storm-induced currents and waves in the Bay of Bengal","authors":"","doi":"10.1016/j.apor.2024.104285","DOIUrl":"10.1016/j.apor.2024.104285","url":null,"abstract":"<div><div>Storm surges, driven by Tropical Cyclones (TCs), pose a threat to the coastal areas of the Bay of Bengal (BoB), causing sediment transport and beach erosion. This study introduces a coupled hydrodynamic (TELEMAC-2D) -wave (TOMAWAC) -morphodynamic (GAIA) model to investigate morphodynamic changes during storm surges. The cyclonic wind is crucial for precisely predicting storm surges, wind waves, and morphodynamic bed evolution. Thus, this study introduced a modified parametric wind model to enhance wind field representation near and far from the cyclone center. The simulated storm surges and wind waves were validated against in-situ observations for TC Hudhud (2014) and TC Varadah (2016), and the simulated morphodynamic bed evolution was validated with field-measured data collected for TC Nivar (2020). Further, this study evaluates the performance of different bed load transport formulations for predicting morphodynamic bed evolution during TC Nivar (2020) under storm-induced currents and waves. Results indicate that the Engelund-Hansen model is most effective for currents alone, while the Bijker model excels for combined currents and waves along the open coast of BoB. The results also indicate that the incorporation of the effect of waves along with currents has enhanced the predictive capability of the coupled model framework.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142586403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Wave Energy Potential and the Role of Extreme Events on South America's Coasts. A Regional Frequency Analysis 南美洲海岸的波浪能潜力和极端事件的作用。区域频率分析

IF 4.3 2区工程技术

Applied Ocean Research Pub Date : 2024-11-04 DOI: 10.1016/j.apor.2024.104280

{"title":"Wave Energy Potential and the Role of Extreme Events on South America's Coasts. A Regional Frequency Analysis","authors":"","doi":"10.1016/j.apor.2024.104280","DOIUrl":"10.1016/j.apor.2024.104280","url":null,"abstract":"<div><div>This study examines wave energy potential and generation capacity from extreme waves along South America's Pacific and Atlantic coasts. Utilizing the Regional Frequency Analysis (RFA) method and the WAVERYS wave reanalysis model, 27 homogeneous regions with distinct wave patterns were identified. There's a notable southward increase in median and average wave heights and energy. Unlike previous studies, this research emphasizes the significant role of extreme wave events, which contribute up to 33 % of the total energy—a critical factor often overlooked in regional energy assessments. In the Pacific, three main zones were delineated, with energy peaks reaching 120 kW/m south of 50°S, while the Atlantic identified two zones with energy values ranging from 10 kW/m to 30 kW/m. Zones between 10°S to 40°S in the Pacific and 30°S to 60°S in the Atlantic stand out as particularly promising for energy harvesting. A comprehensive statistical methodology enabled predictions of wave heights and energy for 50 and 100-year return periods, predominantly utilized generalized Pareto and Gumbel distributions. The study affirms the efficacy of the RFA in improving the understanding of wave dynamics and highlights the necessity of integrating extreme events in energy assessments. This research provides a foundation for advancing wave energy initiatives and coastal risk mitigation in South America.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142577971","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Evaluation, sampling and testing methods for offshore disturbed sands with plastic fines: A case study 含塑性细砂的近海扰动砂的评估、取样和测试方法：案例研究

IF 4.3 2区工程技术

Applied Ocean Research Pub Date : 2024-11-04 DOI: 10.1016/j.apor.2024.104297

{"title":"Evaluation, sampling and testing methods for offshore disturbed sands with plastic fines: A case study","authors":"","doi":"10.1016/j.apor.2024.104297","DOIUrl":"10.1016/j.apor.2024.104297","url":null,"abstract":"<div><div>Sandy seabed, prevalent near continental shelves, often contains fines that obviously affect their apparent behaviour. The variation in the physical properties of sands and fines, the difference between seismic and marine wave loads, and the challenges in obtaining accurate geotechnical parameters and undisturbed samples for analysis make it difficult to effectively evaluate the properties of sands with plastic fines in offshore engineering. To address this issue, a method for discriminating and re-sampling sands with plastic fines is suggested, along with a case study to assess the static and dynamic behaviours of such sands from an offshore site in the South China Sea. In this study, evaluation processes for detecting the presence of fines in sands and classifying them as plastic or non-plastic are first recommended to gain a better understanding of such sands. Then, a reconstitution approach of re-sampling for disturbed sand samples from site and compactness assessment guided by the optimum moisture content, is suggested to restore their in-situ characteristics, addressing the difficulty in obtaining undisturbed sand samples. Subsequently, the failure behavior and shear strain development under cyclic loading are analyzed via a cyclic contour diagram to evaluate their mechanical properties under marine environmental loads. The obtained contour diagrams can be further integrated into the constitutive model in subsequent research and used in finite element analysis to simplify the computation for marine foundation design. These results can provide valuable insights for improving understandings and engineering practices related to sandy seabed with plastic fines in offshore environments.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142577972","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Dynamic response of three different floating platform (OC4, BSS, GVA) using multi-segment mooring system 使用多段系泊系统的三种不同浮式平台（OC4、BSS 和 GVA）的动态响应

IF 4.3 2区工程技术

Applied Ocean Research Pub Date : 2024-11-04 DOI: 10.1016/j.apor.2024.104301

{"title":"Dynamic response of three different floating platform (OC4, BSS, GVA) using multi-segment mooring system","authors":"","doi":"10.1016/j.apor.2024.104301","DOIUrl":"10.1016/j.apor.2024.104301","url":null,"abstract":"<div><div>The design of mooring lines for floating platforms is an essential task to guarantee structure survivability and its components under different metocean conditions. This paper focuses on the application and comparison of the MSM-BMW system across various types of semisubmersible platforms, including the OC4-DeepCwind, the braceless semi-submersible (BSS) with three catenary mooring lines, and the drilling rig GVA 4000 with eight mooring lines. The performance of the BMW mooring system for these three platforms is compared under operational and survival conditions. The hybrid mooring concept is a multi-segment mooring (MSM) arrangement of the catenary and taut, including single buoy and multi-clump weight (BMW), generally named MSM-BMW. Hydrodynamic responses and mooring forces are compared between original and hybrid systems under regular and irregular wave conditions. The dynamic response of the platform is performed utilizing both Morrison theory and three-dimensional radiation/diffraction theory based on the boundary element method (BEM) in ANSYS-AQWA software. The results show that using BMW on the three floating platforms significantly reduces platform motion at low frequencies, with minimal effect on wave-frequency resonance. However, the BMW system increases mooring force at wave frequency, while having a smaller effect at low frequencies. The effectiveness of the BMW system varies across platforms and motion types. The BSS platform shows significant improvement in surge motion, while the GVA platform has the smallest ratio in heave motion. Additionally, the BSS platform demonstrates the least response in pitch motion.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142577973","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Numerical study of underwater acoustic radiation and propagation induced by structural vibration in ocean environments using FEM-BMSBM 利用 FEM-BMSBM 对海洋环境中结构振动引起的水下声辐射和传播进行数值研究

IF 4.3 2区工程技术

Applied Ocean Research Pub Date : 2024-11-01 DOI: 10.1016/j.apor.2024.104294

{"title":"Numerical study of underwater acoustic radiation and propagation induced by structural vibration in ocean environments using FEM-BMSBM","authors":"","doi":"10.1016/j.apor.2024.104294","DOIUrl":"10.1016/j.apor.2024.104294","url":null,"abstract":"<div><div>Understanding underwater acoustic radiation and propagation induced by structural vibration in the ocean environment involves analyzing the interaction between the ocean acoustic field and the structure. For this reason, this paper proposes a novel hybrid scheme integrating the finite element method (FEM), singular boundary method (SBM) and Burton-Miller (BM) technique. The three-dimensional and axisymmetric calculation formulations of the hybrid scheme are presented. By leveraging the respective strengths, the FEM simulates structural free vibrations, the SBM analyzes underwater acoustics in various ocean environments, and the BM technique resolves irregular frequency issues. The accuracy and feasibility of the hybrid FEM-BMSBM are confirmed by comparisons with experimental and other numerical results. The numerical findings demonstrate that the hybrid FEM-BMSBM alleviates the high computational cost of the traditional FEM and the ill-posed problem of the wave superposition method (WSM), and successfully mitigates irregular frequency phenomena of underwater acoustic simulations in various ocean environments. Additionally, the influence of the ocean surface and sediment on the underwater sound field is studied. Numerical study shows that the reflection effects of the ocean surface and sediment cause fluctuations in the underwater sound pressure level curve, and the number of side lobes of the sound pressure level curve increases with the increase of the excitation frequency.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142572013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Estimation of moored ship motions using a combination of machine learning techniques 利用机器学习技术组合估算停泊船只的运动

IF 4.3 2区工程技术

Applied Ocean Research Pub Date : 2024-11-01 DOI: 10.1016/j.apor.2024.104298

{"title":"Estimation of moored ship motions using a combination of machine learning techniques","authors":"","doi":"10.1016/j.apor.2024.104298","DOIUrl":"10.1016/j.apor.2024.104298","url":null,"abstract":"<div><div>The moored ship motions can cause problems for the efficiency of the operation, and for the people and equipment involved. Therefore, being able to predict movements and anticipate possible risk situations is of great interest to operators and the port community. This work presents a methodology applying different machine learning techniques that has allowed positive results to be obtained for this objective, with particular emphasis on the highest values (outliers), which are usually associated with problematic situations. The field campaigns carried out allowed 77 different vessels to be monitored in the outer port of A Coruña (Spain). The techniques used were gradient boosting (GBM), a neural network (DNN), a quantile regression (qReg) and several models generated by stacking (GBM*). The results indicate a lower root mean square error (RMSE) with the use of the latter technique (the validation on the swell is 0.13 m, while the DNN is twice as high), and a better performance on most motions in the outlier subset than those obtained with the individual models (the validation on the outlier subset for the pitch gives an RMSE of 0.12° and 0.2 for the GBM). Finally, the results show that this methodology can be extrapolated to other ports.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142572014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Underwater plasma arc cutting process of oil casing in shallow water environment 浅水环境中石油套管的水下等离子弧切割工艺

IF 4.3 2区工程技术

Applied Ocean Research Pub Date : 2024-11-01 DOI: 10.1016/j.apor.2024.104302

引用次数: 0

Fatigue life analysis of threaded connections in offshore wind turbines 海上风力涡轮机螺纹连接的疲劳寿命分析

IF 4.3 2区工程技术

Applied Ocean Research Pub Date : 2024-10-31 DOI: 10.1016/j.apor.2024.104287

{"title":"Fatigue life analysis of threaded connections in offshore wind turbines","authors":"","doi":"10.1016/j.apor.2024.104287","DOIUrl":"10.1016/j.apor.2024.104287","url":null,"abstract":"<div><div>With the rapid expansion of the installed offshore wind capacity around the world, it is essential to improve the structural integrity of these energy structures for reduced electricity cost and prolonged operational lifespans. An important part of the offshore wind turbine structures is the connection between the monopile foundation and the transition piece. Currently the dominant technology for connecting the monopile to transition piece is using L flanges held together with large-scale bolts. Threaded connections have emerged as a prevalent technology for linking sections of wind turbines, boasting commendable performance despite some inherent drawbacks. This study conducts a comprehensive review of the recommended fatigue design curves for threaded connections in international standards and compares them with the existing fatigue data on medium to large scale bolt sizes. Additionally, the fatigue behaviour of M72 threaded connections has been further analysed by performing new tests with two different values of mean stress. The obtained data from this study have been discussed in terms of the level of conservatism in the recommended fatigue design curves available in international standards for threaded connections. Moreover, the experimental analysis has been combined with numerical and analytical investigations to provide further insight into the life prediction of the threaded connections under fatigue loading conditions.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142561025","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}

引用次数: 0

A novel tool for floating offshore wind substructures design: Validation and definition of design guidelines 用于浮式海上风电子结构设计的新型工具：验证和定义设计准则

IF 4.3 2区工程技术

Applied Ocean Research Pub Date : 2024-10-29 DOI: 10.1016/j.apor.2024.104275

{"title":"A novel tool for floating offshore wind substructures design: Validation and definition of design guidelines","authors":"","doi":"10.1016/j.apor.2024.104275","DOIUrl":"10.1016/j.apor.2024.104275","url":null,"abstract":"<div><div>An efficient frequency-domain numerical tool for the preliminary design of Floating Offshore Wind (FOW) substructures has been developed, investigated, and validated against a state-of-the-art time-domain method. This tool, focused on floating substructures and particularly semi-submersible platforms, aims to expedite the design process. Its originality lies in coupling two novel methods to determine hydrodynamic loads: one estimates linear hydrodynamic coefficients, and the other predicts second-order wave loads. Combined with a simplified frequency domain response model, it enables rapid assessment of the dynamics of various platform designs, thus accelerating preliminary design.</div><div>To minimise computational costs, certain simplifications have been adopted, such as assuming negligible interaction effects between platform members. This assumption enhances the method’s accuracy, particularly when platform columns are spaced further apart for a given diameter. Despite these simplifications, the tool has shown to produce results comparable to existing methods regarding FOW structures’ dynamic behaviour, helping identify the most suitable platform designs for further evaluation in advanced design phases. Its notable efficiency also makes it suitable for sensitivity analyses, enhancing understanding of FOWT dynamic behaviour and quantifying the influence of different parameters on platform design.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142538119","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Numerical investigation of cross waves in water flume with a shoal 带浅滩水槽中横波的数值研究

IF 4.3 2区工程技术

Applied Ocean Research Pub Date : 2024-10-29 DOI: 10.1016/j.apor.2024.104278

{"title":"Numerical investigation of cross waves in water flume with a shoal","authors":"","doi":"10.1016/j.apor.2024.104278","DOIUrl":"10.1016/j.apor.2024.104278","url":null,"abstract":"<div><div>This study examines the symmetrical and anti-symmetrical transverse modes of cross waves in a water flume, particularly focusing on those induced by longitudinally incident waves created by a wavemaker. The primary modes with the lowest mode numbers, symmetrical (1,0) and anti-symmetrical (1,1), were the focus due to their significant energy concentration. Numerical simulations were employed to investigate their occurrence mechanism, evolution processes, and spatial patterns, along with the factors influencing their behavior. Following experimental observations and preliminary analytical solutions, the simulations delved into the detailed behavior of these transverse modes, confirming their presence and characteristics through comparison with analytical solutions. The study reveals that minor perturbations, like water surface disturbances or cross slope variations on the hyperbolic cosine shoal, are essential for exciting these modes. Notably, while symmetrical and anti-symmetrical transverse waves can be initially excited, they cannot maintain a steady form and decay rapidly, indicating their transient nature in the flume environment. The incident wave height and bathymetrical parameter significantly influence the development and characteristics of these waves, with larger incident waves promoting more frequent and varied transverse modes. The interaction between longitudinal and transverse modes on the hyperbolic cosine shoal was also preliminarily observed, aligning with previous studies and suggesting a need for further investigation into their interaction and energy transfer mechanisms.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142538221","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0