Ocean Engineering最新文献_第9页

Evaluation of fatigue performance of post-fire AH32 marine steel welded joints using digital image correlation AH32钢火灾后焊接接头疲劳性能的数字图像相关评价

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-04-15 Epub Date: 2026-02-12 DOI: 10.1016/j.oceaneng.2026.124591

Chenfeng Li , Guanchen Wei , Zixiong Kang , Huilong Ren , Guoqing Feng

To enhance the safety assessment and repair design reliability of ship structures after fire, fatigue tests are conducted on AH32 marine steel butt joints after elevated-temperature exposure. The fatigue stresses at the welded joints are measured using complementary strain gauge and digital image correlation (DIC) techniques. The results demonstrate that, compared to the strain gauge method, DIC technology can directly acquire strain data at the weld based on digital images, enabling a correction of the S-N curve obtained by the strain gauge method. The modified S-N curve reveals a significant influence of post-fire temperature on the fatigue life of the butt joints, with fatigue life first increasing and then decreasing as the temperature rises. Comparative analysis between experimental S-N curves and those recommended by the International Institute of Welding (IIW) reveals systematic assessment differences: The IIW nominal stress curve demonstrates conservative predictions when validated against strain gauge data. In contrast, the IIW notch stress curve exhibits non-conservative behavior when evaluated using DIC results. Finally, scanning electron microscopy (SEM) is employed to analyze the fatigue fracture morphology, explaining the influence of post-fire temperature on fatigue performance from a micromechanical perspective.

为提高船舶结构火灾后的安全评估和修复设计可靠性，对AH32船用钢对接接头进行了高温暴露疲劳试验。采用互补应变片和数字图像相关（DIC）技术测量焊接接头处的疲劳应力。结果表明，与应变片法相比，DIC技术可以直接获取焊缝处基于数字图像的应变数据，从而对应变片法得到的S-N曲线进行校正。修正S-N曲线揭示了火灾后温度对对接接头疲劳寿命的显著影响，随着温度的升高，疲劳寿命先升高后降低。对比分析了实验S-N曲线和国际焊接协会（IIW）推荐的S-N曲线之间的系统评估差异：IIW标称应力曲线在与应变片数据验证时显示出保守的预测。相比之下，当使用DIC结果评估时，IIW缺口应力曲线表现出非保守行为。最后，利用扫描电镜（SEM）对疲劳断口形貌进行了分析，从微观力学角度解释了火后温度对疲劳性能的影响。

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引用次数: 0

Digital twin system for deepwater well construction: Enhancing operational efficiency and safety 深水井建设数字孪生系统：提高作业效率和安全性

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-04-15 Epub Date: 2026-02-09 DOI: 10.1016/j.oceaneng.2026.124378

Dongsheng Xu , Jin Yang , Haiyan Zheng , Bin Chen , De Yan , Jianchun Fan , Qingying Tang , Yingfang Zhou

Deepwater oil and gas resources are vital to global energy supply, yet their development often faces challenges such as prolonged construction cycles, low efficiency, high emissions, and operational failures. To tackle these challenges, this study analyzes how operational and geotechnical factors affect conductor installation time and bearing capacity, during jetting and waiting stages. The intelligent optimization algorithm integrating MT-FCNN, LSTM, and PSO was proposed. A digital twin system for deepwater well construction is established for the first time, employing a modularly coupled architecture to integrate installation and post-installation processes. Validation results show that the DWC system exhibits strong performance in predicting jetting flow rates and controlling ROP during conductor installation. The model achieved a coefficient of determination R² above 0.95 and MAPE below 6 %. In beach-scale experiments, all measured values of time-varying bearing capacity fell within the 95 % confidence interval of the DWC system predictions, demonstrating its high accuracy. Finally, the case study was conducted to analyze the impact of flow rate and waiting time on construction parameters and operational decisions. The findings provide a solid theoretical and technical foundation for intelligent decision-making and enhanced reliability in deepwater well construction.

深水油气资源对全球能源供应至关重要，但其开发往往面临施工周期长、效率低、排放高、操作失败等挑战。为了应对这些挑战，本研究分析了在喷射和等待阶段，操作和岩土因素如何影响导体安装时间和承载能力。提出了将MT-FCNN、LSTM和粒子群算法相结合的智能优化算法。首次建立了用于深水井施工的数字孪生系统，采用模块化耦合架构集成安装和安装后流程。验证结果表明，DWC系统在预测喷流速率和控制钻速方面表现出色。模型的决定系数R2大于0.95，MAPE小于6%。在海滩尺度实验中，实测的时变承载力值均落在DWC系统预测值的95%置信区间内，具有较高的准确性。最后，通过实例分析了流量和等待时间对施工参数和运营决策的影响。研究结果为深水井建设的智能化决策和可靠性提高提供了坚实的理论和技术基础。

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引用次数: 0

Fully nonlinear analysis of wave diffraction by cylinders on a sloping terrain using the Irrotational Green-Naghdi model 用irrotation Green-Naghdi模型对倾斜地形上圆柱波衍射的完全非线性分析

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-04-15 Epub Date: 2026-02-07 DOI: 10.1016/j.oceaneng.2026.124375

Gao-fei Su , Ying Gou , Bo Zhou , Bin Teng , Yuzhu Pearl Li

This study develops a finite element numerical model based on the Irrotational Green-Naghdi (IGN) equations to investigate wave diffraction around an infinitely long array of side-by-side vertical cylinders under head-sea conditions on a sloping seabed. In numerical implementation, the horizontal momentum equations of the IGN equations are solved simultaneously in the local coordinate system of curved boundaries to ensure precise satisfaction of the impermeable boundary condition. Model validation is performed through wave flume experiments measuring wave diffraction around a single vertical cylinder. The numerical predictions of wave forces and free water surface elevations show strong consistency with experimental measurements. The validated model is applied to systematically examine how water depth, seabed slope, cylinder spacing, and cylinder radius influence the wave forces. Numerical analysis demonstrates that wave resonance occurs when the spacing between adjacent cylinders equals half, one, or two times the incident wavelength, amplifying the wave forces. Moreover, for incident wave frequencies just below the resonance frequency, the steep seabed can cause peaks or troughs of the wave surface elevation behind the cylinders to shift between adjacent cylinders, resulting in wave force reduction.

本研究建立了一个基于Irrotational Green-Naghdi （IGN）方程的有限元数值模型，以研究在倾斜海床上，在头海条件下，波浪绕无限长并排垂直圆柱体阵列的衍射。在数值实现中，IGN方程的水平动量方程在弯曲边界的局部坐标系中同时求解，以确保精确满足不渗透边界条件。通过波浪水槽实验，测量绕单个垂直圆柱体的波衍射，对模型进行验证。波浪力和自由水面高度的数值预测结果与实验结果具有很强的一致性。应用验证的模型系统地研究了水深、海底坡度、柱体间距和柱体半径对波浪力的影响。数值分析表明，当相邻圆柱体之间的间距等于入射波长的一半、一倍或两倍时，会发生波共振，从而放大波浪力。此外，对于刚好低于共振频率的入射波频率，陡峭的海床会使柱面后波面高程的波峰或波谷在相邻柱面之间发生移位，导致波浪力减小。

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引用次数: 0

Cavitation-sand synergistic erosion in Francis turbines: Three-Phase flow simulation and runner optimization for enhanced operational stability 混流式水轮机的空化-砂协同侵蚀：三相流模拟和转轮优化，以提高运行稳定性

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-04-15 Epub Date: 2026-02-07 DOI: 10.1016/j.oceaneng.2026.124563

Longgang Sun , Tingting Ji , Zhaoning Wang , Yanyan Li , Pengcheng Guo

Francis turbines operating under sediment-laden conditions suffer from cavitation and sediment erosion, whose synergistic interaction critically threatens operational stability. This study employs a three-phase numerical framework for a Francis turbine and develops a multi-objective optimization strategy integrating hydraulics enhancement, cavitation alleviation, and erosion resistance. Two inter-blade cavitation vortices and a sheet-like flow-separation cavitation are identified at different guide vane openings, causing flow blockage, velocity redistribution, and particle accumulation near vortex peripheries. Erosion is strongly correlated with these vortical structures, exhibiting high intensity at vortex boundaries due to elevated particle velocity and concentration, whereas remaining weak in vortex cores and wall-vortex interfaces. Runner optimization with increased inlet-edge twist effectively modifies the flow pattern and sediment transport. Under two inter-blade cavitation vortex conditions, optimized hydraulic efficiency increases by 2.858% and 1.846%, with cavitation volume reduced by 33.405% and 62.265%, and average blade erosion rate decreased by 19.659% and 23.363%, respectively. Under the sheet-like cavitation condition, hydraulic efficiency increases by 0.169%, accompanied by reductions of 91.898% in cavitation volume and 30.868% in erosion rate. Morphologically, high-erosion regions induced by inter-blade vortices are significantly alleviated. These findings elucidate cavitation-erosion coupling mechanisms and confirm the effectiveness of integrated optimization in suppressing cavitation and erosion.

混流式水轮机在泥沙淤积条件下运行时存在空化和泥沙侵蚀问题，二者的协同作用严重威胁着水轮机的运行稳定性。本文采用三相数值框架对混流式水轮机进行了研究，并开发了一种集水力增强、空化缓解和抗冲蚀为一体的多目标优化策略。在不同导叶开度处发现了两个叶片间空化涡和一个片状流分离空化涡，在涡周附近造成流动阻塞、速度重分布和颗粒堆积。侵蚀与这些涡旋结构密切相关，由于粒子速度和浓度的提高，在涡旋边界处表现出高强度，而在涡旋核心和壁面涡旋界面处则表现出弱强度。优化流道，增加入口边缘扭转，有效地改变了水流模式和泥沙输运。两种叶片间空化涡条件下，优化后的水力效率分别提高了2.858%和1.846%，空化体积分别减小了33.405%和62.265%，叶片平均侵蚀率分别降低了19.659%和23.363%。在片状空化条件下，水力效率提高了0.169%，空化体积减小了91.898%，侵蚀速率减小了30.868%。在形态上，叶片间涡诱导的高侵蚀区明显减轻。这些发现阐明了空化-侵蚀耦合机制，证实了综合优化在抑制空化和侵蚀方面的有效性。

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引用次数: 0

Experimental study and analysis of flow field characteristics of floating breakwaters with different cross-sectional shapes 不同断面形状浮式防波堤流场特性的试验研究与分析

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-04-15 Epub Date: 2026-02-06 DOI: 10.1016/j.oceaneng.2026.124527

Bin Sun , Jianyu Wang , Danyang Di , Chunyang He , Feifei Wang

As a critical protective facility in marine engineering, floating breakwaters serve as an essential technical means for mitigating marine environmental risks and ensuring the safety of engineering structures. Given that the shape of floating breakwaters significantly influences their energy dissipation effectiveness, this study systematically investigates the wave attenuation efficiency and dynamic response characteristics of rectangular, trapezoidal, and triangular floating breakwaters. In the study, six floating breakwater models were constructed by designing trapezoidal floating breakwaters with six different base angles. A combined approach of physical wave tank experiments and numerical simulations was employed to analyze the wave attenuation performance and dynamic response characteristics of these six models. The findings reveal that under constant wave height, draft depth, and period conditions, the 45° trapezoidal floating breakwater, with its gentler slope, more effectively suppresses mooring force growth, thereby extending the service life of the floating structure. Furthermore, precise adjustment of the inclination angle enables optimization of the breakwater's wave-attenuation performance under various operational conditions.

浮式防波堤是海洋工程中重要的防护设施，是减轻海洋环境风险、保障工程结构安全的重要技术手段。鉴于浮式防波堤的形状对其耗能效果有显著影响，本研究系统地研究了矩形、梯形和三角形浮式防波堤的消波效率和动力响应特性。通过设计六种不同底角的梯形浮式防波堤，构建了六个浮式防波堤模型。采用物理波槽实验和数值模拟相结合的方法，对这6种模型的波衰减性能和动力响应特性进行了分析。研究结果表明，在一定波高、吃水深度和周期条件下，45°梯形浮式防波堤坡度较缓，能更有效地抑制锚泊力的增长，从而延长浮式结构的使用寿命。此外，倾斜角度的精确调整可以优化防波堤在各种操作条件下的减波性能。

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引用次数: 0

Mechanical behavior of marine coral sand - coral clay mixtures reinforced with bionic honeycomb polymer grid: Experimental and artificial intelligence methods 仿生蜂窝聚合物网格增强海洋珊瑚砂-珊瑚粘土混合物的力学行为：实验和人工智能方法

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-04-15 Epub Date: 2026-02-05 DOI: 10.1016/j.oceaneng.2026.124406

Kaiwei Xu , Jiaqi Luo , Jiaming Zhao , Danda Shi , Zhiming Chao , Titi Sui

Marine coral clay, a critical fine-grained component in reclaimed island foundations for ocean engineering, is typically mixed with marine coral sand to form composite foundation soil that governs offshore infrastructure stability. To address accurate strength prediction of this soil reinforced by 3D-printed bionic honeycomb polymer grid (BHPG), this study develops a CNN-LSTM model, uses SHapley Additive exPlanations (SHAP) to quantify input parameter importance, and validates it with 1200 triaxial shear tests. Results confirm high accuracy and identify reinforcement type, layers, and confining pressure as key factors, while a derived empirical formula enables rapid engineering use. A user-friendly graphical user interface (GUI) is also developed for ocean engineering practitioners to get real-time strength predictions. This work reduces test costs, advances deep learning-marine engineering integration, and supports BHPG application in reclaimed islands and offshore platforms.

海洋珊瑚粘土是海洋工程填海岛屿地基的关键细粒成分，通常与海洋珊瑚砂混合形成复合地基土，控制海上基础设施的稳定性。为了准确预测3d打印仿生蜂窝聚合物网格（BHPG）加固土的强度，本研究建立了CNN-LSTM模型，使用SHapley加性解释（SHAP）来量化输入参数的重要性，并通过1200次三轴剪切试验对其进行验证。结果证实了较高的准确性，并确定了钢筋类型、层数和围压是关键因素，同时推导出的经验公式使工程快速应用。为海洋工程从业者提供了一个用户友好的图形用户界面（GUI），以获得实时强度预测。这项工作降低了测试成本，推进了深度学习与海洋工程的整合，并支持BHPG在填海岛屿和海上平台的应用。

引用次数: 0

Free-field response of a seawater-frozen seabed system under obliquely incident SV waves 斜入射SV波作用下海水-冻结海床系统的自由场响应

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-04-15 Epub Date: 2026-02-05 DOI: 10.1016/j.oceaneng.2026.124525

Huipeng Jiang , Qiang Ma

Submarine permafrost occurs in shallow cold-region shelves, where seismic shaking may threaten offshore infrastructure. This study derives an analytical free-field solution for a coupled seawater-frozen seabed-bedrock system subjected to obliquely incident plane SV waves. Seawater is modelled as an inviscid compressible acoustic layer, the frozen seabed as a frozen saturated three-phase porous medium described by LCAM (Linearised Contact-Adhesion Model), and the bedrock as an elastic half-space. Using Helmholtz-decomposed potentials, Snell's law, and the transmission-reflection (T-R) method, closed-form frequency-domain displacements are obtained, capturing P-SV mode conversion within the frozen layer. Dimensionless horizontal and vertical surface-to-base transfer functions are defined, and pulse-excited time histories are reconstructed via inverse FFT. The solution is verified against published benchmark results for coupled seawater-seabed-bedrock systems. Parametric analyses examine temperature, porosity, incident angle, cementation-related Poisson's ratio, ice-skeleton contact condition, and depth. Results show that both the overlying seawater and the incident angle strongly reshape the transfer functions, with the vertical response particularly sensitive to fluid-solid coupling and interference/mode conversion. Lower temperatures reduce displacements and shift dominant peaks to higher frequencies, whereas higher porosity and weaker inter-phase constraint increase amplification. The formulation provides efficient baseline motions for subsequent seawater-frozen seabed-structure interaction analyses at laterally uniform sites.

海底永久冻土层位于浅层寒区大陆架，地震震动可能威胁到海上基础设施。本文导出了受斜入射平面SV波作用的海水-冻结海床-基岩耦合系统的解析自由场解。海水被建模为无粘性的可压缩声学层，冻结的海底被建模为LCAM（线性接触-粘附模型）描述的冻结饱和三相多孔介质，基岩被描述为弹性半空间。利用亥姆霍兹分解势、斯涅尔定律和透射反射（T-R）方法，获得了封闭形式的频域位移，捕获了冻结层内的P-SV模式转换。定义了无因次水平和垂直面基传递函数，并通过逆FFT重构了脉冲激励时程。该解决方案与已发表的海水-海床-基岩耦合系统的基准结果进行了验证。参数分析包括温度、孔隙度、入射角、胶结相关泊松比、冰骨架接触条件和深度。结果表明，上覆海水和入射角对传递函数有强烈的重塑作用，其中垂向响应对流固耦合和干涉/模态转换尤为敏感。较低的温度降低了位移，使主导峰向更高的频率移动，而较高的孔隙度和较弱的相间约束增加了放大。该公式为后续在横向均匀位置的海水-冻结海床-结构相互作用分析提供了有效的基线运动。

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引用次数: 0

Convex formulation of the maritime fleet size and mix problem considering battery electric ships 考虑纯电动船舶的海上船队规模和混合问题的凸公式

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-04-15 Epub Date: 2026-02-12 DOI: 10.1016/j.oceaneng.2026.124415

Antti Ritari, Jani Romanoff, Kari Tammi

This paper focuses on the problem of determining a minimum-cost fleet of battery electric ships for a given liner shipping operation. The problem is strongly nonlinear and includes integer decision variables, which make it intractable for most real-world instances. The conventional approach in the literature is to formulate a linear approximation by restricting available ship types to a small number of predetermined alternatives. Contrary to the conventional linearization approach, this paper models the nonlinearities directly. We show that the nonlinearities have a hidden convex form uncovered by changes of variables. Computational experiments show that our convex formulation achieves 15.1% lower fleet cost on average and reduces solve time by at least 10 ×  compared to the linear formulation. The solve time advantage is attributed to the elimination of binary variables for ship type selection. Our implementation is available at https://github.com/ajritari/cvxfleet.

本文主要研究在给定的班轮运输条件下，如何确定一个成本最低的纯电动船队。该问题是强非线性的，并且包含整数决策变量，这使得它对于大多数现实世界的实例来说都很棘手。文献中的传统方法是通过将可用的船型限制为少数预先确定的备选方案来制定线性近似。与传统的线性化方法相反，本文直接对非线性进行建模。我们证明了非线性具有一种由变量变化所揭示的隐凸形式。计算实验表明，与线性公式相比，我们的凸公式平均降低了15.1%的车队成本，并将求解时间减少了至少10 × 。求解时间上的优势在于消除了船型选择的二元变量。我们的实现可以在https://github.com/ajritari/cvxfleet上获得。

引用次数: 0

Survivability strategy for an eagle wave energy converter based on CFD modeling 基于CFD建模的鹰波能量转换器生存性策略

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-04-15 Epub Date: 2026-02-12 DOI: 10.1016/j.oceaneng.2026.124604

Shanxun Yang , Songwei Sheng , Xianyuan Yang , Xiaolong Dai , Xinhui Chen

Severe sea states pose significant challenges to the survivability of wave energy converters (WECs). To address collision problems caused by excessive motion of the floating body observed during sea trials of the Eagle WEC, a CFD numerical model based on overset mesh approach was developed to investigate the motion response. The model was systematically validated against 1:30-scale physical experiments under three scenarios, including empty wave tank, floating body only and PTO included. The results demonstrate excellent agreement. Using the full-scale numerical model, the effects of power take-off (PTO) load and ballast on the pitch response of the floating body were investigated. The results indicate that increasing the PTO load effectively suppresses the motion response of the floating body and enhances the operational safety margin of the device; increasing ballast can suppress upward motion but amplifies the downward response, its impact on operational safety is twofold. The coordinated ballast–PTO adjustment strategy was proposed and evaluated under irregular wave conditions. The results show that, during an extreme wave event with a maximum instantaneous wave height of 6.51 m, by increasing ballast while maintaining a high PTO load, the motion envelope can be shifted downward and kept within the operational safety limits.

恶劣的海况对波浪能转换器（WECs）的生存能力提出了重大挑战。为了解决Eagle WEC海上试验中观测到的浮体过度运动导致的碰撞问题，开发了基于过偏移网格方法的CFD数值模型来研究运动响应。通过1:30比例尺的物理实验对模型进行了系统验证，包括空波槽、仅浮体和含PTO三种场景。结果显示了极好的一致性。采用全尺寸数值模型，研究了载力和压载对浮体俯仰响应的影响。结果表明：增大PTO载荷可有效抑制浮体的运动响应，提高装置的运行安全裕度；增加压载可以抑制上升运动，但会放大下降响应，对运行安全的影响是双重的。提出了非规则波条件下的压舱- pto协调调整策略，并对其进行了评价。结果表明，在最大瞬时波高为6.51 m的极端波浪事件中，通过增加压载量同时保持较高的PTO负载，可以将运动包络线向下移动并保持在运行安全范围内。

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引用次数: 0

Experimental and numerical study on the four-point bending behaviour of small-scale steel pipes with dents 带凹痕小钢管四点弯曲特性的试验与数值研究

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-04-15 Epub Date: 2026-02-10 DOI: 10.1016/j.oceaneng.2026.124500

Utkarsh Bhardwaj , Baiqiao Chen, C. Guedes Soares

This paper investigates the structural behaviour of small-diameter steel pipes with dents subjected to four-point bending. Experiments are conducted to determine the influence of small pre-induced dents on the pipes’ bending performance and failure characteristics. The tests involve measuring the load-displacement response and identifying the critical failure modes. Numerical simulations using the finite element method are performed to model the bending process and validate the experimental results. The simulations provide insights into the stress distribution and deformation patterns of the dented pipes. The comparison between experimental and numerical results demonstrates a good correlation, indicating the accuracy of the simulation model. This research contributes to understanding the effects of dents on the structural integrity of steel pipes and offers a validated approach for future predictive modelling.

本文研究了带凹痕的小直径钢管在四点弯曲作用下的结构性能。通过试验研究了预诱导小凹痕对管材弯曲性能和破坏特性的影响。试验包括测量荷载-位移响应和识别临界破坏模式。利用有限元方法对弯曲过程进行了数值模拟，验证了实验结果。模拟提供了对凹痕管道的应力分布和变形模式的深入了解。实验结果与数值结果的对比表明，仿真模型具有良好的相关性，表明了仿真模型的准确性。这项研究有助于理解凹痕对钢管结构完整性的影响，并为未来的预测建模提供了一种有效的方法。

引用次数: 0