Applied Ocean Research最新文献_第4页

Optimization of spudcan penetration and influence on caisson foundation 优化钻孔和对沉箱地基的影响

IF 4.3 2区工程技术

Applied Ocean Research Pub Date : 2024-08-26 DOI: 10.1016/j.apor.2024.104186

{"title":"Optimization of spudcan penetration and influence on caisson foundation","authors":"","doi":"10.1016/j.apor.2024.104186","DOIUrl":"10.1016/j.apor.2024.104186","url":null,"abstract":"<div><p>The penetration of spudcans have adverse effects on pre-existing bucket foundations during the blade lifting process of offshore wind power systems, which brings uncertainties for the design and construction of bucket foundations. This study employs the Euler-Lagrange method to explore the influence of spudcan penetration on the adjacent caissons in homogeneous clay within a large deformation finite element (LDFE) model. The LDFE model is validated against centrifuge tests data, with good agreement obtained. Parametric study is then conducted to explore, (i) the influence of the angle between vessel and caissons on the movements of the caisson, and (ii) potential influence factors on the movements of the caisson with an optimal angle between the vessel and caissons, including soil properties, dimensions of caisson and spudcan, and the distance between spudcan and caissons. The results show that 60° is the optimal angle between the vessel and caissons that results in the smallest movement of the caisson, and the caisson foundation inclination angle ranges between 0° and 0.025°, when the pile shoe penetration progress ranges between 0.1 and 1.0. An empirical formula is proposed to predict the rotational angle of caisson with the optimal angle. The study establishes a quantitative approach to assess the influence of the spudcan penetration on existing three-caisson jacket foundations, which provides guidance for the design and construction of offshore wind turbine bucket foundations.</p></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142077375","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

The structural assessment for concrete structure on the onset of cracking with respect to steel corrosion 混凝土结构对钢筋锈蚀开裂的结构评估

IF 4.3 2区工程技术

Applied Ocean Research Pub Date : 2024-08-24 DOI: 10.1016/j.apor.2024.104200

{"title":"The structural assessment for concrete structure on the onset of cracking with respect to steel corrosion","authors":"","doi":"10.1016/j.apor.2024.104200","DOIUrl":"10.1016/j.apor.2024.104200","url":null,"abstract":"<div><p>The present study concerns structural behaviour of a marine bridge in terms of cracking exposed to a seawater environment under the risk of chloride-induced corrosion with the axial loading. In the modelling process, the corrosion propagation was expressed into the rust formation on the steel surface, while the axial load was given 5–30 % to the compressive strength of concrete. The interfacial gap between steel and concrete was taken 10 µm, imposing the buffering capacity against a build-up of the rust at the steel-concrete interface. As a result, it was found that the tensile damage produced the cracking on the surface of concrete with a minimal corrosion of steel, which was further developed into the inner concrete depth with increasing corrosion formation. Also, an increase in the axial load resulted in an increase in the surface cracking at a given rust formation. At the steel-concrete interface, the cracking was much affected by the compressive deformation arising from a build-up of rust, as being limited in the vicinity in the interfacial zone, presumably due to the limited rust formation. A combination of steel corrosion and axial loading imposes the accelerated cracking of concrete structure then to rapidly deteriorate its serviceability.</p></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142050207","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

On the effects of wind and operating conditions on mooring line tensions for floating offshore wind turbine 风力和运行条件对浮式海上风力涡轮机系泊线张力的影响

IF 4.3 2区工程技术

Applied Ocean Research Pub Date : 2024-08-24 DOI: 10.1016/j.apor.2024.104197

{"title":"On the effects of wind and operating conditions on mooring line tensions for floating offshore wind turbine","authors":"","doi":"10.1016/j.apor.2024.104197","DOIUrl":"10.1016/j.apor.2024.104197","url":null,"abstract":"<div><p>The present work addresses a significant topic in the current understanding of the structural dynamic behavior of mooring lines for floating offshore wind turbines (FOWT) in operating condition and aims to contribute to the ongoing efforts to enhance the performance and reliability of floating offshore wind energy systems. The present paper investigates the impact of operating conditions on mooring line tension for FOWT. A numerical model of a spar-type FOWT developed in Orcaflex, validated with experimental data, was employed to perform dynamic analyses and to calculate the most probable maximum tension values for scenarios involving wave-only and combined wind-wave actions under various operating conditions. Results indicate that the peak frequency of oscillations is primarily influenced by wave frequency and remain unchanged in operating conditions, but the significant variability in the structure’s displacement response leads to a notable fluctuation in tensions within the mooring lines. Specifically, higher tensions are observed in the upwind region while lower tensions are evident in the downwind area. However, for prolonged periods it becomes apparent that operating conditions induce high tension levels across all mooring lines, while also exerting a damping contribution related to wave-induced effects. The study underscores that the primary detrimental factor affecting mooring lines in operating conditions is the widening of the operating tension range.</p></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0141118724003183/pdfft?md5=76e6c5859625aa9efee72368aabaaab1&pid=1-s2.0-S0141118724003183-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142050208","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

Investigation on the oblique water entry of the flared cavity 关于喇叭形空腔斜向进水的研究

IF 4.3 2区工程技术

Applied Ocean Research Pub Date : 2024-08-24 DOI: 10.1016/j.apor.2024.104156

{"title":"Investigation on the oblique water entry of the flared cavity","authors":"","doi":"10.1016/j.apor.2024.104156","DOIUrl":"10.1016/j.apor.2024.104156","url":null,"abstract":"<div><p>An experimental study of the oblique water entry of a flared cavity is reported in this paper. A numerical model is established that takes gas compressibility into account. This model effectively captures the additional flow phenomena that occur due to gas expansion and contraction within the cavity. There is a significant fluctuation phenomenon during the oblique water entry of the flared cavity, which is reflected not only in the movement of the water entry bubble but also in the slamming pressure. This fluctuation phenomenon is caused by the bottom cavity of the flared cavity, which adds the additional processes of external fluid inflow and internal fluid outflow compared with the closed-bottom structure, leading to additional flow due to conventional flow separation. When the external liquid flows into the cavity, the additional flow reduces the velocity potential of the fluid near the flow separation point, causing the bubble diameter near the flow separation point to contract. At the same time, the external liquid inflow causes the gas in the cavity to compress and the slamming pressure to increase. When the liquid flows out of the cavity, the additional flow increases the velocity potential of the fluid near the flow separation point, causing the bubble diameter near the flow separation point to expand. Meanwhile, the internal fluid outflow causes the gas in the cavity to expand and the slamming pressure to decrease.</p></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142050114","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

The surrogate model for short-term extreme response prediction based on ANN and Kriging algorithm 基于 ANN 和 Kriging 算法的短期极端响应预测代用模型

IF 4.3 2区工程技术

Applied Ocean Research Pub Date : 2024-08-24 DOI: 10.1016/j.apor.2024.104196

{"title":"The surrogate model for short-term extreme response prediction based on ANN and Kriging algorithm","authors":"","doi":"10.1016/j.apor.2024.104196","DOIUrl":"10.1016/j.apor.2024.104196","url":null,"abstract":"<div><p>Numerical simulation is a common method for calculating the short-term extreme response of floating offshore wind turbines (FOWTs). However, it requires significant computational resources. This study presents a dynamic response database for a 5MW semi-submersible FOWT under complex environmental conditions, including wind speed, effective wave height, and wave spectral peak period, using a numerical model. The peak over threshold (POT) method can be used to obtain the parametric database of short-term extreme responses, which includes the short-term extreme response distribution parameters for four responses: float surge, mooring tension, outward bending moment at the leaf root surface (OoPBM) and tower base pitching moment (TBPM). And the parameter database is applied to train models such as the Genetic Algorithm optimization Back Propagation neural network (GA-BP) and Kriging algorithm models. The research indicates that a correlation can be established between environmental conditions and short-term extreme response parameters using two algorithms. The accuracy of surrogate model prediction for some parameters can be improved by grouping the data based on wind speed and training separately. Additionally, selecting the appropriate surrogate model for each parameter separately can improve the accuracy of short-term extreme response prediction.</p></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142058031","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

An experimental study of a rectangular floating breakwater with flexible curtains as wave-dissipating components 以柔性帷幕作为消波部件的矩形浮式防波堤实验研究

IF 4.3 2区工程技术

Applied Ocean Research Pub Date : 2024-08-21 DOI: 10.1016/j.apor.2024.104185

{"title":"An experimental study of a rectangular floating breakwater with flexible curtains as wave-dissipating components","authors":"","doi":"10.1016/j.apor.2024.104185","DOIUrl":"10.1016/j.apor.2024.104185","url":null,"abstract":"<div><p>In this study, the flexible curtains are attached to the bottom of a rectangular floating breakwater as wave-dissipating components. Through a comprehensive experimental investigation, the wave attenuation, motion responses, and mooring forces of the proposed floating breakwater are examined, with a particular focus on the effects of wave height and the hanging length and porosity of the flexible curtain. Meanwhile, comparative analyses are conducted with the stand-alone rectangular floating breakwater and with attaching one rigid slotted barrier. Our experimental results indicate that one underhanging flexible curtain can augment wave attenuation across all tested wave conditions, which is comparable to the rigid slotted barrier. Furthermore, attaching two flexible curtains contributes to a more significant enhancement for harbor or coastal protection, especially against long waves. This can be attributed to the buffer function of flexible curtains, and the increased added mass induced by the water body confined between them, which increases the natural period of floating breakwaters. Furthermore, the attachment of the flexible curtains significantly suppresses the motion responses of the breakwater, which can alleviate the undesirable strong mooring forces. In general, increasing the length or decreasing the porosity of flexible curtains leads to similar trends in the performance of floating breakwaters. The flexible curtains have been proven to be effective wave-dissipating components for rectangular floating breakwaters.</p></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142020542","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

The influence of flow field bottom effect and sand cloud effect on the hydrodynamic performance and stability of bottom trawling otter board under tilted attitudes 倾斜姿态下流场底效应和沙云效应对底层拖网獭板水动力性能和稳定性的影响

IF 4.3 2区工程技术

Applied Ocean Research Pub Date : 2024-08-21 DOI: 10.1016/j.apor.2024.104176

{"title":"The influence of flow field bottom effect and sand cloud effect on the hydrodynamic performance and stability of bottom trawling otter board under tilted attitudes","authors":"","doi":"10.1016/j.apor.2024.104176","DOIUrl":"10.1016/j.apor.2024.104176","url":null,"abstract":"<div><p>To explore how bottom and sand cloud effects influence the hydrodynamic performance and stability of bottom trawling otter board under tilted attitudes, this study combines numerical simulations by oval cambered otter board and flume tank experiments verification. By assessing drag and lift coefficients (<em>C<sub>D</sub>,C<sub>L</sub></em>), center-of-pressure coefficients (<em>C<sub>pc</sub>, C<sub>pb</sub></em>) and longitudinal moment (<em>M<sub>y</sub></em>) in different heel angles, the study evaluates the impact under the two effects on hydrodynamics and stability. Findings reveal that inward and outward tilting increases <em>C<sub>D</sub></em> maximally under sand cloud effect, while minimizing it under broad-field only water conditions; <em>C<sub>L</sub></em> is maximal under bottom effect and minimal under broad-field only water conditions. For forward and backward tilting, <em>C<sub>D</sub></em> under sand cloud effect is greater than that under bottom effect, with minimal values in broad-field only water conditions; <em>C<sub>L</sub></em> is maximal under bottom effect and minimal under broad-field only water conditions. Additionally, stability varies across different flow field conditions, deteriorating along the <em>x</em>-axis due to bottom and sand cloud effects, while maintaining relative stability along the <em>y</em>-axis and <em>z</em>-axis. This study demonstrates that the bottom effect and sand cloud effect alter the otter board's proximity to the seabed and the fluid viscosity, leading to differences in hydrodynamic performance and stability under inclined attitudes. The findings aim to provide insights for the use and design of bottom trawling otter boards, ensuring stability and safety under various operating conditions and attitudes.</p></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142020541","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

Trajectory tracking control for unmanned amphibious surface vehicles with actuator faults 存在致动器故障的无人驾驶两栖水面飞行器的轨迹跟踪控制

IF 4.3 2区工程技术

Applied Ocean Research Pub Date : 2024-08-20 DOI: 10.1016/j.apor.2024.104182

引用次数: 0

“Assessment of combined wind and wave energy in European coastal waters using satellite altimetry.” "利用卫星测高法评估欧洲沿海水域的风能和波浪能组合"。

IF 4.3 2区工程技术

Applied Ocean Research Pub Date : 2024-08-19 DOI: 10.1016/j.apor.2024.104184

{"title":"“Assessment of combined wind and wave energy in European coastal waters using satellite altimetry.”","authors":"","doi":"10.1016/j.apor.2024.104184","DOIUrl":"10.1016/j.apor.2024.104184","url":null,"abstract":"<div><p>In this study, the combined wind and wave energy potential assessment is presented for various locations in European coastal waters. The objective is to investigate the feasibility of satellite altimetry-based assessments of combined wind/wave renewable energy potential on the European shelf. The study is motivated by the potential reduction in energy supply variability by combining wind and wave. The method consists of using a homogenized multi-mission altimeter database available by the European Space Agency Sea State Climate Change Initiative (Sea_State_cci) that comprises 26 years of data, from January 1991 to December 2018, that allows extending the time range and spatial coverage to estimate site wind and wave power densities. An empirical model is used to estimate the wave energy period from the altimeter Ku band significant wave height and radar backscatter coefficient required to compute the wave power density. The results show that wind/wave energy is relatively correlated in the Mediterranean but not in the North Atlantic sites studied. Thus, the Western North Atlantic sites are the most adequate places for wind and wave farms, from the point of view of combined exploitation.</p><p>The different characteristics of the studied sites show some correspondence between variability and mean wave power, which is an essential input to a marine renewable energy strategy in any jurisdiction. The level of overall variability decreases with an increase in mean wave power, related to the higher power swell waves are not highly correlated with the local wind.</p></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142006722","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

Investigation of tracked mining vehicles' driving performance at varying travel speeds by experimental and numerical simulation 通过实验和数值模拟研究履带式采矿车辆在不同行驶速度下的驾驶性能

IF 4.3 2区工程技术

Applied Ocean Research Pub Date : 2024-08-19 DOI: 10.1016/j.apor.2024.104142

{"title":"Investigation of tracked mining vehicles' driving performance at varying travel speeds by experimental and numerical simulation","authors":"","doi":"10.1016/j.apor.2024.104142","DOIUrl":"10.1016/j.apor.2024.104142","url":null,"abstract":"<div><p>The design of a tracked mining vehicle (TMV) that can efficiently and safely travel on the deep seabed is the core technology in the deep-sea polymetallic nodule mining system, and one of the main aspects influencing the TMV's driving performance and efficiency is its travel speed. To overcome the current limitations of low mining vehicle efficiency and susceptibility to slipping and sinking, this study investigates the impact of travel speed on vehicle performance based on laboratory model experiments and numerical simulation methods. Initially, track driving model experiments were conducted, revealing that traction force increases with travel speed, analyzing the influence on the stage-wise variation of shear strength-displacement relationship between the track and sediment interface. An optimized traction force calculation model was proposed, and applied in multi-body dynamics software and validating its rationality. Multi-body dynamics simulation experiment results indicate a significant increase in the settlement amount of TMVs with increasing travel speed. However, the magnitude of the travel speed changes the variation pattern of settlement amount with travel displacement, and it was found that the slip rate during stable vehicle traveling is positively correlated with travel speed. The impact of travel speed on the performance of TMVs traveling on sediment eroded by jets in actual engineering was also analyzed. It is found that excessive or insufficient travel speed is detrimental to the performance of TMVs. In this study, when the travel speed is 0.7 m/s, the effect of weakening the mechanical strength of eroded sediment on TMV's driving performance is relatively small. This research provides a scientific theoretical basis for improving mining vehicle efficiency and enhancing mining capability.</p></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142012466","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