Journal of Ocean Engineering and Science最新文献_第8页

Cross-sectional mechanical characteristics and sensitivity analysis of unbonded flexible risers under axial loads 轴向载荷作用下无粘结柔性立管的截面力学特性及灵敏度分析

IF 13 1区工程技术 Q1 ENGINEERING, MARINE

Journal of Ocean Engineering and Science

Pub Date : 2025-08-01 Epub Date: 2023-08-29 DOI: 10.1016/j.joes.2023.08.005

Xiansheng Zhang , Weiping Huang , Weilin Ma , Lei Su , Haoyu Tian , Yongchun Yang

Unbonded flexible risers exhibit complex structures. Different structural layers can withstand axial loads and exhibit different degrees of coupled deformation. Based on the different material properties and structural forms of each layer of an unbonded flexible riser, the structural layers are divided into three types: cylindrical, steel helical, and polymer helical layers. This study establishes a theoretical model of flexible risers under axial loads based on the law of conservation of energy and the geometry of deformation, and deduces theoretical expressions for the axial load and axial stiffness of flexible risers. MATLAB was used to compile calculation programs to calculate the cross-sectional mechanical properties of flexible risers under axial tensile and compressive loads and to compare the calculation results with the experimental results and the results of other researchers to verify the reliability of the theoretical derivation and calculation programs. By further calculating the cross-sectional force distribution of each structural layer of the flexible risers under axial tensile loads, it is clarified that the tensile armor layer is the main component that can withstand axial tensile loads. A sensitivity analysis of the helix angle and number of helical strips of the tensile armor layer on the tensile properties of flexible risers was conducted; the results show that the helix angle had a more obvious influence on the tensile properties of flexible risers. The results of this study can provide a reference for the structural design and optimization of flexible risers.

无粘结柔性立管结构复杂。不同的结构层可以承受不同的轴向载荷，并表现出不同程度的耦合变形。根据无粘结柔性隔水管各层材料性能和结构形式的不同，将其结构层分为圆柱层、钢螺旋层和聚合物螺旋层三种类型。基于能量守恒定律和变形几何，建立了轴向载荷作用下柔性立管的理论模型，推导出了柔性立管轴向载荷和轴向刚度的理论表达式。利用MATLAB编写计算程序，对柔性立管在轴向拉伸和压缩载荷作用下的截面力学性能进行计算，并将计算结果与实验结果和其他研究者的结果进行对比，验证理论推导和计算程序的可靠性。通过进一步计算柔性隔水管各结构层在轴向拉伸载荷作用下的截面受力分布，明确拉伸护甲层是承受轴向拉伸载荷的主要构件。对柔性隔水管拉伸层的螺旋角和螺旋条数进行了敏感性分析；结果表明，螺旋角对柔性立管拉伸性能的影响更为明显。研究结果可为柔性立管的结构设计和优化提供参考。

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引用次数: 0

Comparative life cycle impact assessment of offshore support vessels powered by alternative fuels for sustainable offshore wind operations using machine learning 使用机器学习对可持续海上风力发电替代燃料驱动的海上支持船的生命周期影响进行比较评估

IF 13 1区工程技术 Q1 ENGINEERING, MARINE

Journal of Ocean Engineering and Science

Pub Date : 2025-08-01 Epub Date: 2023-10-30 DOI: 10.1016/j.joes.2023.10.005

Shoaib Ahmed , Tie Li , Shi Yan Li , Run Chen

Offshore Anchor handling tug supply (AHTS) vessels, a type of offshore support vessel, are critical for the operations related to handling anchors of offshore structures, oil rigs, and wind turbines, towing them to remote deep-sea locations, and securing them in place. Amidst growing concerns regarding the environmental footprints of carbon-based fuels and impending carbon taxation, the International Maritime Organization, policymakers, classification societies, shipping firms, and stakeholders are seeking cleaner alternatives. LNG (Liquefied natural gas) and Green ammonia as energy vectors are considered among the top contenders for future clean alternatives for offshore vessels. This study evaluated the environmental performance of newly built AHTS vessels powered by LNG and Green ammonia as marine fuels designed for offshore operations. This environmental impact assessment study uses IPCC and Environmental footprint methodologies. Considered broad impact groups: Global warming, human toxicity, eutrophication, ecotoxicity, and atmosphere-related impacts, and analyzed the process impacts. This study uses Supervised machine learning algorithms such as the Random forest, Decision tree, and XGBOOST models for environmental performance evaluation and prediction. The study reveals that the recently manufactured AHTS vessel, utilizing conventional fuels like Heavy fuel oil, Marine diesel oil, and LNG, exhibits significantly increased GTP 100 and GWP 100 emission levels per tonne-kilometer when compared to green ammonia, with a 44 % and 10.6 % rise compared to Heavy fuel oil, respectively. Furthermore, the XGBOOST regression model outperformed the Random forest and Decision tree models in predictive accuracy for GWP 100. It is analyzed and proposed that effectively managing unsustainable processes would minimize environmental footprints and reduce carbon, nitrogen oxide, LNG, and ammonia-based emissions.

海上锚处理拖船供应（AHTS）船是一种海上支持船，对于处理海上结构、石油钻井平台和风力涡轮机的锚，将其拖到遥远的深海位置并将其固定在适当位置至关重要。随着人们对碳基燃料的环境足迹和即将到来的碳税的日益关注，国际海事组织、政策制定者、船级社、航运公司和利益相关者正在寻求更清洁的替代品。LNG（液化天然气）和绿色氨作为能源载体被认为是未来海上船舶清洁替代品的主要竞争者。本研究评估了由LNG和Green氨作为海上作业船用燃料的新建AHTS船的环境性能。本环境影响评估研究采用IPCC和环境足迹方法。考虑了广泛的影响组：全球变暖、人类毒性、富营养化、生态毒性和与大气相关的影响，并分析了过程影响。本研究使用随机森林、决策树和XGBOOST模型等监督式机器学习算法进行环境绩效评价和预测。研究表明，最近制造的AHTS船，使用传统燃料，如重油、船用柴油和液化天然气，与绿色氨相比，每吨公里的GTP 100和GWP 100排放水平显著增加，与重油相比分别增加了44%和10.6%。此外，XGBOOST回归模型在GWP 100的预测精度上优于随机森林和决策树模型。分析并提出，有效管理不可持续的过程将最大限度地减少环境足迹，减少碳、氮氧化物、液化天然气和氨基排放。

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引用次数: 0

Review on researches and main influencing factors on mechanical properties of offshore wind power cables 海上风电电缆机械性能研究及主要影响因素综述

IF 13 1区工程技术 Q1 ENGINEERING, MARINE

Journal of Ocean Engineering and Science

Pub Date : 2025-08-01 Epub Date: 2024-07-05 DOI: 10.1016/j.joes.2024.06.001

Xu Qin , Mengmeng Zhang , Shixiao Fu , Huailiang Li , Jing Hou , Yuwang Xu

With the rapid development of offshore wind farms, the usage and quantity of offshore wind power cables have increased significantly. However, the existing research on offshore wind power cables still cannot meet the stringent requirements of deep-sea environments. Therefore, improving the understanding of the mechanical performance of offshore wind power cables and their influencing factors holds profound implications. This paper provides an overview of existing numerical and experimental researches on mechanical performance of offshore wind power cables. The relationship between various mechanical properties of offshore wind power cables and their complex cross-sectional structural forms are systematically elaborated. The limitations of these researches are analyzed. And a prospective outlook on future research directions is provided, aiming to guide reliable engineering applications of offshore wind power cables in complex marine environments.

随着海上风电场的快速发展，海上风电电缆的使用量和数量都有了显著的增长。然而，现有的海上风电电缆研究仍不能满足深海环境的严格要求。因此，提高对海上风电电缆力学性能及其影响因素的认识具有深远的意义。本文综述了海上风电电缆力学性能的数值和实验研究现状。系统阐述了海上风电电缆各种力学性能与其复杂截面结构形式之间的关系。分析了这些研究的局限性。并对未来的研究方向进行了展望，旨在指导海上风电电缆在复杂海洋环境中的可靠工程应用。

引用次数: 0

A machine learning model for fast approximation of free-surface Green's function and its application 自由曲面格林函数快速逼近的机器学习模型及其应用

IF 13 1区工程技术 Q1 ENGINEERING, MARINE

Journal of Ocean Engineering and Science

Pub Date : 2025-08-01 Epub Date: 2023-08-19 DOI: 10.1016/j.joes.2023.08.002

Ke Zhan, Renchuan Zhu, Dekang Xu

In potential flow theory, the accurate and efficient calculation of free-surface Green's functions is essential for solving hydrodynamic issues. Given the impressive performance of machine learning methods in nonlinear function fitting, the present study utilizes an effective machine learning model called StripeGF for numerical approximation. In this model, equidistant horizontal datum lines are arranged in the computational domain away from the singularity, and Green's function and its derivatives on each line are fitted by a multi-layer perceptron (MLP) with a single input. Based on the first-order ordinary differential equation (ODE) that they satisfy, the fourth-order Runge-Kutta method is used to solve the Green's function and its derivatives between adjacent lines. In the domain nearing the singularity, a double-input MLP is applied. Use the Romberg quadrature to create a double-precision data set for training and validation, the numerical results demonstrate that StripeGF outperforms all 4 comparison methods in terms of efficiency and has accuracy of at least 4 digits in more than 99.9% of all zones. The boundary element program improved by StripeGF is verified in the hydrodynamic calculation of S175, showing good accuracy and reliability.

在势流理论中，准确有效地计算自由面格林函数对于解决流体动力学问题至关重要。鉴于机器学习方法在非线性函数拟合中的出色表现，本研究利用一种称为StripeGF的有效机器学习模型进行数值逼近。在该模型中，在远离奇异点的计算域内布置等距离的水平基准线，并使用单输入的多层感知器（MLP）拟合格林函数及其在每条基准线上的导数。在满足一阶常微分方程（ODE）的基础上，利用四阶龙格-库塔法求解格林函数及其邻线导数。在接近奇异点的区域，采用双输入MLP。使用Romberg正交建立双精度数据集进行训练和验证，数值结果表明，StripeGF在效率方面优于所有4种比较方法，并且在所有区域的准确率均超过99.9%。StripeGF改进的边界元程序在S175的水动力计算中得到了验证，显示出良好的精度和可靠性。

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引用次数: 0

Numerical simulation of violent interactions between dam break flow and a floating box using a modified MPS method 用改进的MPS方法数值模拟溃坝流与浮箱的剧烈相互作用

IF 13 1区工程技术 Q1 ENGINEERING, MARINE

Journal of Ocean Engineering and Science

Pub Date : 2025-08-01 Epub Date: 2023-08-19 DOI: 10.1016/j.joes.2023.08.003

Date Li , Huaixin Zhang , Guangfei Qin

The Moving particle semi-implicit (MPS) method is a widely used approach to simulate the violent interactions between dam break flow and downstream structures. However, most of these simulations involved fixed downstream structures and rarely considered floating objects. In this study, a modified MPS method, named MPS-SP-MG-PS method, is proposed to simulate violent interactions between dam break flow and a floating box. The proposed method includes below modifications: (1) the MPS-SP scheme with a split-pressure Poisson equation; (2) a modified space potential particle (SPP) scheme; and (3) a mixed pressure gradient and a novel particle shifting (PS) technique. Two cases are simulated, one considers heave motion only, and another considers both heave and pitch. Slamming, wave-on-deck and severe motions are involved in the cases. In order to evaluate the effect of these modifications, several numerical models with different combinations of the modifications are tested as well. Numerical results demonstrate the enhancement on stability and accuracy by these modifications: the MPS-SP scheme ensures the stability of heave motion at the initial stage; the modified SPP scheme maintains reasonable distance between free surface particles; and the combination of the mixed pressure gradient and the novel PS technique shows its accuracy in estimating box motions. Furthermore, the numerical results from the MPS-SP-MG-PS method are well consistent with experimental and existing numerical results in terms of box motions, surface elevations, fluid profiles, and slamming pressure. This indicates that the MPS-SP-MG-PS method is suitable for simulating violent interactions between dam break flow and floating structures.

运动粒子半隐式（MPS）方法是一种广泛应用于溃坝水流与下游结构物剧烈相互作用模拟的方法。然而，这些模拟大多涉及固定的下游结构，很少考虑漂浮物。本文提出了一种改进的MPS方法，即MPS- sp - mg - ps方法，用于模拟溃坝水流与浮箱之间的剧烈相互作用。提出的方法包括以下修改：(1)带分压泊松方程的MPS-SP格式；(2)改进的空间势粒子（SPP）格式；(3)混合压力梯度和新型粒子移动（PS）技术。模拟了两种情况，一种只考虑升沉运动，另一种同时考虑升沉和俯仰。撞击、甲板上的波浪和剧烈的运动都涉及到这些案件。为了评价这些修改的效果，还对几种不同修改组合的数值模型进行了测试。数值结果表明：MPS-SP方案保证了升沉运动初始阶段的稳定性；改进的SPP方案保持了自由表面粒子之间的合理距离；将混合压力梯度与新PS技术相结合，证明了该方法在估计箱体运动方面的准确性。此外，MPS-SP-MG-PS方法的数值结果与实验和现有的数值结果在箱体运动、地表高程、流体剖面和撞击压力等方面具有很好的一致性。这表明MPS-SP-MG-PS方法适用于模拟溃坝水流与浮体结构之间的剧烈相互作用。

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引用次数: 0

Run length encoding based weld seam detection from point clouds of ship stiffened panel 基于行程长度编码的船舶加筋板点云焊缝检测

IF 13 1区工程技术 Q1 ENGINEERING, MARINE

Journal of Ocean Engineering and Science

Pub Date : 2025-08-01 Epub Date: 2024-08-02 DOI: 10.1016/j.joes.2024.07.002

Jun Li , Zhen Chen , Chongben Ni , Puhao Lei

A vision-based weld seam detector is crucial for intelligent welding in ship stiffened panel as it influences the working efficiency of welding robots. This paper introduces an innovative Run Length Encoding (RLE) based Line Segment Detector (RSD) that is capable of extracting line segments from point clouds. The RLE is firstly employed to compress point cloud data by encoding them into runs. Then, the directional feature of significant line segments is determined according to the analysis of level line angles, facilitating a global line segment detection mechanism. This enables RSD to capture more complete line segments compared to region-based detection methods. Notably, this method obviates the need for manual parameter adjustments and does not require any prior information. The effectiveness and superiority of RSD are confirmed by testing various workpieces in a laboratory setting and comparing its performance with other detectors.

基于视觉的焊缝检测仪对船舶加筋板的智能焊接至关重要，它直接影响到焊接机器人的工作效率。本文介绍了一种新颖的基于运行长度编码（RLE）的线段检测器（RSD），该检测器能够从点云中提取线段。首先利用RLE对点云数据进行压缩，将点云数据进行编码。然后，根据水平线角的分析，确定重要线段的方向特征，实现全局线段检测机制；与基于区域的检测方法相比，这使得RSD能够捕获更完整的线段。值得注意的是，这种方法不需要手动调整参数，也不需要任何先验信息。通过在实验室环境中测试各种工件，并将其性能与其他探测器进行比较，证实了RSD的有效性和优越性。

引用次数: 0

Real-time prediction of ship motions based on the reservoir computing model 基于水库计算模型的船舶运动实时预测

IF 13 1区工程技术 Q1 ENGINEERING, MARINE

Journal of Ocean Engineering and Science

Pub Date : 2025-06-01 Epub Date: 2024-07-23 DOI: 10.1016/j.joes.2024.07.001

Yu Yang, Tao Peng, Shijun Liao, Jing Li

Real-time prediction of ship motions is crucial for ensuring the safety of offshore activities. In this study, we investigate the performance of the reservoir computing (RC) model in predicting the motions of a ship sailing in irregular waves, comparing it with the long short-term memory (LSTM), bidirectional LSTM (BiLSTM), and gated recurrent unit (GRU) networks. The model tests are carried out in a towing tank to generate the datasets for training and testing the machine learning models. First, we explore the performance of machine learning models trained solely on motion data. It is found that the RC model outperforms the LSTM, BiLSTM, and GRU networks in both accuracy and efficiency for predicting ship motions. Besides, we investigate the performance of the RC model trained using the historical motion and wave elevation data. It is shown that, compared with the RC model trained solely on motion data, the RC model trained on the motion and wave elevation data can significantly improve the motion prediction accuracy. This study validates the effectiveness and efficiency of the RC model in ship motion prediction during sailing and highlights the utility of wave elevation data in enhancing the RC model’s prediction accuracy.

船舶运动的实时预测对于确保海上活动的安全至关重要。在这项研究中，我们研究了水库计算（RC）模型在预测不规则波浪中航行的船舶运动方面的性能，并将其与长短期记忆（LSTM）、双向LSTM （BiLSTM）和门控循环单元（GRU）网络进行了比较。模型测试在拖曳槽中进行，以生成用于训练和测试机器学习模型的数据集。首先，我们探索仅在运动数据上训练的机器学习模型的性能。研究发现，RC模型在预测船舶运动的精度和效率上都优于LSTM、BiLSTM和GRU网络。此外，我们还研究了使用历史运动和波浪高程数据训练的RC模型的性能。结果表明，与只训练运动数据的RC模型相比，训练运动和波浪高程数据的RC模型可以显著提高运动预测精度。本研究验证了RC模型在航行过程中船舶运动预测中的有效性和有效性，突出了波浪高程数据在提高RC模型预测精度方面的作用。

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引用次数: 0

A numerical model for stress relaxation analysis of sealing systems in nonbonded pipe end fittings 非粘结管端管件密封系统应力松弛分析的数值模型

IF 13 1区工程技术 Q1 ENGINEERING, MARINE

Journal of Ocean Engineering and Science

Pub Date : 2025-06-01 Epub Date: 2023-10-13 DOI: 10.1016/j.joes.2023.10.001

Kunpeng Chen , Mengmeng Zhang , Shixiao Fu , Bing Zhao , Chunmiao Luo

Nonbonded flexible pipes consist of polymer materials that experience stress relaxation at high temperatures, which ultimately affects the sealing performance of end sealing systems. To assess stress relaxation curves under varying temperatures and pre-strains, this paper conducts both tensile and stress relaxation tests on PVDF materials. To describe the stress relaxation characteristics of these materials, the Prony series is utilized. In order to identify the parameters of the series, the paper employs the Levenberg-Marquardt method of nonlinear regression. A finite element model is established to verify the accuracy of the parameter identification method. Subsequently, the paper establishes a two-dimensional axisymmetric finite element model of the sealing system in the end fitting, while taking into account fluid pressure inside the pipeline using a pressure penetration method. The impact of stress relaxation on the sealing performance is then discussed. Finally, the paper alters the coefficients of the Prony series to explore their significance on the sealing performance of the sealing system.

非粘结柔性管由聚合物材料组成，在高温下会发生应力松弛，最终影响端部密封系统的密封性能。为了评估不同温度和预应变下的应力松弛曲线，本文对PVDF材料进行了拉伸和应力松弛试验。为了描述这些材料的应力松弛特性，使用了proony系列。为了识别序列的参数，本文采用了非线性回归的Levenberg-Marquardt方法。建立了有限元模型，验证了参数辨识方法的准确性。随后，采用压力渗透法，考虑管道内流体压力，建立了端部管件密封系统的二维轴对称有限元模型。讨论了应力松弛对密封性能的影响。最后，通过对proony系列系数的修改，探讨其对密封系统密封性能的影响。

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引用次数: 0

An advanced laboratorial measurement technique of scour topography based on the fusion method for 3D reconstruction 基于三维重建融合方法的先进冲刷地形实验室测量技术

IF 13 1区工程技术 Q1 ENGINEERING, MARINE

Journal of Ocean Engineering and Science

Pub Date : 2025-06-01 Epub Date: 2023-12-14 DOI: 10.1016/j.joes.2023.12.002

Kan Huang , Xiaoni Wu , Zhiliang Lin

Local scour is a phenomenon that occurs around water-blocking structures such as bridge piers, pile foundations, and pipelines, which threatens seriously the safety of structures. The laboratory test based on wave and flow tanks is an effective way investigating the local scour around piles. The measurement of scour depth and topography is an important basis for this type of experimental analysis, which can help the researchers to perform a quantitative analysis on the scour mechanism. The conventional measurement methods in scouring experiments have limitations in terms of operational efficiency, measurement range, and cost. Therefore, an advanced experimental measurement technique based on the RGB-D sensor and the 3D reconstruction algorithm was proposed in this work to provide the full topography information around target zone after scour. Experiments applying this 3D reconstruction method were conducted for the practical scour tests. The impact of water on the application of this technique was discussed as well. The results showed that the new technique has good accuracy in scour topography description and scour depth measurement. This work provides a new measure technique for laboratory scour tests. The proposed method has a broad application prospect in measurements for such experimental scenes.

局部冲刷是发生在桥墩、桩基、管道等堵水构筑物周围的一种现象，严重威胁构筑物的安全。基于波流罐的室内试验是研究桩周局部冲刷的有效手段。冲刷深度和地形的测量是这类实验分析的重要依据，可以帮助研究人员对冲刷机理进行定量分析。传统的冲刷试验测量方法在操作效率、测量范围和成本等方面存在局限性。因此，本文提出了一种基于RGB-D传感器和三维重建算法的先进实验测量技术，以提供冲刷后目标区域周围的完整地形信息。应用该三维重构方法进行了实际冲刷试验。讨论了水对该技术应用的影响。结果表明，新技术在冲刷地形描述和冲刷深度测量方面具有较好的精度。为室内冲刷试验提供了一种新的测量技术。该方法在此类实验场景的测量中具有广阔的应用前景。

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引用次数: 0

Visual deep learning with physics constraints for local scour evolution prediction at monopiles 利用物理约束进行可视化深度学习，预测单桩局部冲刷演变情况

IF 13 1区工程技术 Q1 ENGINEERING, MARINE

Journal of Ocean Engineering and Science

Pub Date : 2025-06-01 Epub Date: 2024-04-21 DOI: 10.1016/j.joes.2024.04.001

Bingjing Lu , Jingjing Zuo , Mohammad Shahhosseini , Hui Wang , Haichao Liu , Minxi Zhang , Guoliang Yu

Local scour threatens the safety of marine structures, necessitating the precise prediction of scour evolution around these structures. A visually oriented deep learning model, called Disentangled Physics-constrained Prediction (DPP), was proposed in this study to predict scour evolution at monopiles reliably. It integrates scouring physics with advanced video prediction techniques through a two-branch architecture. The Physics-constrained Recurrent Module (PRModule) branch leverages Recurrent Neural Networks (RNNs) for temporal differentiation, ensuring accurate prediction of scouring-related physical information. Meanwhile, the Convolutional Long-Short-Term Memory (ConvLSTM) branch captures spatial and temporal dynamics in scouring videos, focusing on the prediction of residual features. DPP outperformed three baseline models in predicting the scour evolution at monopiles. Across three scouring scenarios, DPP achieved a 14.2% decrease in Root Mean Squared Error, a 14.7% reduction in Mean Absolute Error, and an 8.1% increase in Structural Similarity on average, compared to the best-performing baseline model. The predicted scouring frames are found to agree well with the true frames, demonstrating DPP's potential as a valuable tool to protect marine infrastructures.

局部冲刷威胁着海洋构筑物的安全，需要对构筑物周围的冲刷演变进行精确预测。本研究提出了一种面向视觉的深度学习模型，称为解纠缠物理约束预测（DPP），以可靠地预测单桩冲刷演化。它通过双分支架构集成了精练物理和先进的视频预测技术。物理约束循环模块（PRModule）分支利用循环神经网络（rnn）进行时间分化，确保准确预测与冲刷相关的物理信息。同时，卷积长短期记忆（ConvLSTM）分支捕捉视频的时空动态，重点关注残差特征的预测。DPP在预测单桩冲刷演化方面优于三个基线模型。与表现最好的基线模型相比，在三种搜索场景中，DPP的均方根误差降低了14.2%，平均绝对误差降低了14.7%，结构相似性平均提高了8.1%。预测的冲刷框架与真实框架一致，证明了DPP作为保护海洋基础设施的宝贵工具的潜力。

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引用次数: 0