Ocean Engineering最新文献_第6页

Offshore wind support structures – Evaluation of size effects and influencing factors on the fatigue performance of butt-welded joints using an updated database 海上风力支撑结构。使用更新数据库对对接焊接接头疲劳性能的尺寸效应和影响因素的评价

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-28 DOI: 10.1016/j.oceaneng.2026.124370

H. Bartsch , S. Röscher , M. Braun , J. Maljaars , J. Schubnell , M. Rauch , A. Chahardehi , A. Mehmanparast

Offshore wind turbine support structures, such as monopiles, require high fatigue resistance at welded connections, particularly around the circumferential welds. This paper reviews the influence of plate thickness on the fatigue performance of welded butt joints and presents a statistical evaluation of relevant fatigue test data. The analysis combines the European fatigue database (DASt Database) with newly available data related to welded offshore wind structures to ensure representativeness for modern monopile structures. The unfiltered European fatigue database contains more than 4700 data points for butt welds, but its heterogeneity in materials, welding processes, and specimen geometries produces a large scatter. After filtering for offshore wind-relevant conditions, by including thick plates (t ≥ 25 mm), various sub-grades of S355 structural steel, double-sided butt welds, submerged arc welding, axial loading condition, and load ratios of R ≥ 0 the dataset reduces drastically but yields consistent results based on relevant test data. In this subset, the characteristic fatigue resistance corresponds to FAT 90, while the inverse slope of the S–N curve increased to m ≈ 3.45, which is higher than the EN 1993-1-9 standard assumption of m = 3 but in excellent agreement with the monopile-specific D curve in DNV-RP-C203 standard. The newly added offshore wind related datasets, particularly for plate thicknesses of 40 mm and 50 mm, confirm these findings. They demonstrate a fatigue life reduction trend with increasing the plate thickness for t ≥ 25 mm, while the thickness correction formulation in EN 1993-1-9 standard has been found to produce a trend that falls at the lower bound of the scatter. Moreover, the variations in the load ratios of R ≥ 0 and the yield strength in various sub-grades of S355 steel were found to have no significant influence on fatigue resistance. Overall, the results demonstrate that targeted filtering and integration of offshore wind-specific data provide a more realistic basis for fatigue design and life assessment of monopile support structures.

海上风力涡轮机支撑结构，如单桩，在焊接连接处，特别是在周向焊缝处，要求具有高的抗疲劳性。本文综述了钢板厚度对焊接对接接头疲劳性能的影响，并对相关疲劳试验数据进行了统计评价。该分析将欧洲疲劳数据库（DASt数据库）与最新的海上焊接风结构相关数据相结合，以确保现代单桩结构的代表性。未经过滤的欧洲疲劳数据库包含超过4700个对接焊缝数据点，但其材料、焊接工艺和试样几何形状的异质性产生了很大的分散。在对海上风力相关条件进行过滤后，通过纳入厚板（t≥25 mm）、S355结构钢的各种子级、双面对接焊、埋弧焊、轴向加载条件和R≥0的载荷比，数据集大幅减少，但基于相关测试数据的结果一致。在该子集中，特征疲劳抗力对应于FAT 90，而S-N曲线的反斜率增加到m≈3.45，高于EN 1993-1-9标准中m = 3的假设，但与DNV-RP-C203标准中单桩特异性D曲线非常吻合。新增加的海上风电相关数据集，特别是40毫米和50毫米板厚度的数据集，证实了这些发现。当钢板厚度≥25mm时，其疲劳寿命随厚度的增加呈下降趋势，而EN 1993-1-9标准中的厚度修正公式在散点的下界处呈现下降趋势。此外，R≥0载荷比和屈服强度的变化对S355钢的抗疲劳性能没有显著影响。总体而言，结果表明，有针对性地过滤和整合海上风场数据为单桩支撑结构的疲劳设计和寿命评估提供了更现实的依据。

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引用次数: 0

Cambered blade effects on fixed-pitch and variable-pitch Darrieus hydrokinetic turbine performance 弯曲叶片对定节距和变节距Darrieus水轮机性能的影响

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-28 DOI: 10.1016/j.oceaneng.2026.124410

Dhanjita Medhi, Atul Kumar Soti

This study presents Computational Fluid Dynamics (CFD) simulations of a Darrieus hydrokinetic turbine equipped with cambered blade profiles, evaluated over a range of Tip Speed Ratios (

T S R

s) from 0.5 to 3.5. Using a 2-D CFD simulation, the investigation is performed with 3 asymmetric blade profiles: NACA 2408, NACA 2418, and NACA 2424. By subjecting these cambered profile blades, the influence of blade asymmetry on the power coefficient (

C_{p}

) is analyzed for both Fixed-Pitch (FP) and Variable-Pitch (VP) vertical-axis turbines. The variable-pitch motion is achieved through sinusoidal blade pitching with different pitch angle amplitudes ranging from

2 ° - 10 °

. The numerical simulations are carried out by solving the nonlinear Unsteady Reynolds Average Navier-Stokes (URANS) equations and SST

k - ω

turbulence model to capture the turbulent flow around the turbine rotor. The effect of cambered profile blade thickness on the hydrodynamic performance of FP and VP turbines is analyzed, revealing that the NACA 2424 profile performs best in both configurations. In terms of

C_{p}

, the FP turbine with NACA 2418 blade profile achieved a maximum

C_{p}

of 0.30 at a TSR of 1.5, while a VP turbine with NACA 2424 profile reached a peak

C_{p}

of 0.225 at a TSR of 1. Computational results show that, for small-scale hydrokinetic applications, FP turbines with asymmetric blade profiles outperform VP turbines operating at lower pitch amplitudes with the same blade profiles in terms of hydrodynamic efficiency.

本研究采用计算流体动力学（CFD）模拟了一种带有弯曲叶型的Darrieus水动力涡轮，在0.5到3.5的叶尖速比（TSR）范围内进行了评估。利用二维CFD模拟，对NACA 2408、NACA 2418和NACA 2424三种非对称叶片进行了研究。通过对这些弯曲叶片进行实验，分析了叶片不对称对定螺距和变螺距垂直轴涡轮功率系数的影响。变桨距运动是通过桨叶的正弦俯仰来实现的，桨叶俯仰的俯仰幅度在2°~ 10°之间。通过求解非线性非定常雷诺平均Navier-Stokes （URANS）方程和SST k−ω湍流模型进行了数值模拟，以捕获涡轮转子周围的湍流。分析了弧形叶片厚度对FP和VP涡轮水动力性能的影响，结果表明NACA 2424型在两种配置下都表现最佳。Cp方面，NACA 2418叶型的FP涡轮在TSR为1.5时最大Cp为0.30，而NACA 2424叶型的VP涡轮在TSR为1时最大Cp为0.225。计算结果表明，在小型水动力应用中，非对称叶型的FP涡轮在水动力效率方面优于相同叶型、低桨距振幅的VP涡轮。

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引用次数: 0

Turbulence characteristics and energy cascade in wave-current flow over an adverse sloping bed 逆坡床上波浪流的湍流特性和能量级联

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-28 DOI: 10.1016/j.oceaneng.2026.124427

Souvik Roy , Koustuv Debnath , Vikas Kumar Das

Wave-current interactions play a crucial role in shaping coastal dynamics, influencing turbulence characteristics, sediment transport, and morphodynamic evolution. This study experimentally investigates turbulent flow behaviour over an adverse sloping bed under combined wave-current forcing, addressing the limited understanding of slope effects in such environments. An open-channel flume with a 1:16 bed slope was used to generate steady currents at three Reynolds numbers (Re = 21,600, 32,400, and 43,200) superimposed with surface waves at frequencies of 0.6 Hz and 0.8 Hz. High-resolution Acoustic Doppler Velocimetry (ADV) measurements were analysed to obtain mean velocity profiles, turbulence intensities, Reynolds stresses, probability density functions (PDFs), and Integral and Kolmogorov length scales. Spectral and wavelet analyses were employed to identify the dominant turbulence scales and coherent structures that govern energy transfer. Results show that wave frequency has a strong influence on turbulence dynamics, with higher frequencies amplifying turbulence intensity and Reynolds stress, particularly at lower Reynolds numbers. Compared with a plain bed, the adverse slope introduces additional pressure gradients, flow separation, and instability, significantly modifying boundary-layer characteristics and energy distribution. This study links turbulence structure to the energy-cascade framework through a new energy-ratio parameter, revealing nonlinear energy exchange between waves and currents.

波流相互作用在塑造海岸动力学、影响湍流特征、沉积物输运和形态动力学演化中起着至关重要的作用。本研究通过实验研究了波浪-流联合作用下在不利斜坡床上的湍流行为，解决了对这种环境中斜坡效应的有限理解。采用1:16河床坡度的明渠水槽，产生三种雷诺数（Re = 21,600, 32400和43,200）的稳定电流，并叠加频率为0.6 Hz和0.8 Hz的表面波。分析了高分辨率声学多普勒测速（ADV）测量结果，以获得平均速度剖面、湍流强度、雷诺兹应力、概率密度函数（pdf）以及积分和Kolmogorov长度尺度。利用光谱和小波分析确定了控制能量传递的主要湍流尺度和相干结构。结果表明，波浪频率对湍流动力学影响较大，频率越高湍流强度越大，雷诺数越低时雷诺数越大。与平原层相比，逆坡面引入了额外的压力梯度、流动分离和不稳定性，显著改变了边界层特征和能量分布。本研究通过一个新的能量比参数将湍流结构与能量级联框架联系起来，揭示了波流之间的非线性能量交换。

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引用次数: 0

Localized anomaly detection and recovery of marine engine data to support digital twin development in shipping 船舶发动机数据的局部异常检测和恢复，以支持航运业的数字孪生发展

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-28 DOI: 10.1016/j.oceaneng.2026.124356

Mahmood Taghavi , Lokukaluge P. Perera

Digitization has made its way into the shipping industry in recent years. Consequently, a vast amount of data is being generated, recorded, and utilized in the development of Digital Twins (DTs) designed for various applications, such as condition monitoring and efficiency improvements in industrial systems. Due to different reasons, such as malfunctions in onboard data acquisition systems in vessels, an assortment of anomalies and missing values can be observed among measured performance and navigation data in vessels. These issues can degrade the performance of the DT models and, therefore, the credibility of the resulting analysis. Consequently, cleaning the dataset is a crucial step in developing any data-driven model development framework, such as DTs in shipping. This process includes the identification, isolation, and ultimately, treatment of anomalies and missing values in datasets from ocean-going vessels. The main contribution of this study is the introduction of a data quality improvement framework for identifying and isolating anomalies, as well as recovering the missing values by estimating appropriate values. To better illustrate the proposed framework, a dataset from an oceangoing vessel is used as a sample case study, and the results of applying the proposed methods to it are presented.

近年来，数字化已经进入航运业。因此，大量的数据被生成、记录并用于为各种应用而设计的数字双胞胎（dt）的开发，例如工业系统的状态监测和效率提高。由于各种原因，如船舶机载数据采集系统故障，在船舶的测量性能和导航数据中可以观察到各种异常和缺失值。这些问题会降低DT模型的性能，从而降低结果分析的可信度。因此，清理数据集是开发任何数据驱动的模型开发框架（例如交付中的dt）的关键步骤。这一过程包括识别、隔离并最终处理来自远洋船舶的数据集中的异常和缺失值。本研究的主要贡献是引入了一个数据质量改进框架，用于识别和隔离异常，以及通过估计适当的值来恢复缺失值。为了更好地说明所提出的框架，以一艘远洋船舶的数据集为例进行了示例案例研究，并给出了将所提出的方法应用于该数据集的结果。

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引用次数: 0

Unified probabilistic model for axial strength of concrete-filled aluminum alloy tube columns with circular and square cross-sections 圆形和方形截面铝合金混凝土管柱轴向强度统一概率模型

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-28 DOI: 10.1016/j.oceaneng.2026.124384

Hao Cheng , Junlei Tang , Zecheng Yu , Mingfei Yang , Bo Yu

Concrete-filled aluminum alloy tube (CFAT) columns play a vital role in the offshore jacket platforms due to their excellent corrosion resistance, high strength-to-weight ratio, and low maintenance requirements. However, traditional deterministic models fail to account for the epistemic and aleatory uncertainties inherent in CFAT columns, which consequently poses significant challenges to the safety and durability assessment of offshore jacket platforms. In order to overcome this limitation, a novel unified probabilistic model was proposed for predicting the axial strength of CFAT columns with circular and square cross-sections. A new unified deterministic model for the axial strength of CFAT columns was developed first by incorporating the equivalent cross-sectional area of the polygon CFAT columns, the effective constraint zone principle, the Lamé solution, and the unified strength theory. A unified probabilistic model was then formulated by integrating the proposed deterministic model into a Markov Chain Monte Carlo Bayesian framework. Meanwhile, the predictive performance of the proposed model was verified through comparisons with traditional deterministic models, design codes, and experimental data. Finally, the confidence intervals and probabilistic distribution functions derived from the proposed model were utilized to calibrate existing deterministic models for CFAT columns with circular and square cross-sections.

混凝土填充铝合金管（CFAT）柱具有优异的耐腐蚀性、高强度重量比和低维护要求，在海上导管架平台中发挥着至关重要的作用。然而，传统的确定性模型未能考虑到CFAT柱固有的认知和选择性不确定性，这给海上导管架平台的安全性和耐久性评估带来了重大挑战。为了克服这一限制，提出了一种新的统一概率模型来预测圆形和方形截面的CFAT柱的轴向强度。本文首先结合多边形CFAT柱的等效截面积、有效约束区原理、lam解和统一强度理论，建立了CFAT柱轴向强度的统一确定性模型。然后将确定性模型整合到马尔可夫链蒙特卡罗贝叶斯框架中，形成统一的概率模型。同时，通过与传统确定性模型、设计规范和实验数据的比较，验证了该模型的预测性能。最后，利用该模型得到的置信区间和概率分布函数对圆形和方形截面的CFAT柱的现有确定性模型进行校准。

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引用次数: 0

Enhancing prediction performance of experimental pressure on square cylinders with CFD data and deep transfer learning 利用CFD数据和深度迁移学习提高方形圆柱体实验压力预测性能

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-27 DOI: 10.1016/j.oceaneng.2026.124425

Zhixin Liu , Haotian Dong , Caiyao Hu , Xiaoqing Du

Accurate estimation of fluid-induced loading is critical for bluff-body aerodynamics, which is sometimes limited by insufficient sensors used in wind tunnel experiments. With the aid of computational fluid dynamics (CFD) and deep transfer learning, the prediction performance of experimental pressure on square cylinders is improved. This is achieved by combining Transfer Learning (TL) with Proper Orthogonal Decomposition (POD) and Long Short-Term Memory (LSTM) networks. The TL-POD-LSTM framework was tested for uniform flow past a single and two tandem square cylinders. The prediction errors, aerodynamic coefficients, pressure coefficients, and pressure time-series are discussed considering various training tap numbers. For a single square cylinder, the root-mean-square errors are reduced by 68 %, 40 %, and 9 % for 4, 12, and 20 training taps by introducing CFD data and TL-POD-LSTM, suggesting the proposed method has a better performance when the training data is insufficient. The errors of aerodynamic coefficients and Strouhal number are within 4 % using only 4 training taps. The regions of non-Gaussian pressure and extremes of instantaneous pressure are also well predicted by TL-POD-LSTM. For two tandem square cylinders, three spacing ratios 1.25, 3, and 4 were tested, and the proposed method works well in reproducing the pressure on the downstream cylinder.

流体诱导载荷的准确估计对崖体空气动力学至关重要，有时由于风洞实验中使用的传感器不足而受到限制。利用计算流体力学（CFD）和深度迁移学习技术，提高了方形圆柱体实验压力的预测性能。这是通过将迁移学习（TL）与适当正交分解（POD）和长短期记忆（LSTM）网络相结合来实现的。TL-POD-LSTM框架通过一个和两个串联方形圆柱体进行了均匀流动测试。讨论了不同训练分锥数下的预测误差、气动系数、压力系数和压力时间序列。对于单个方形圆柱体，通过引入CFD数据和TL-POD-LSTM， 4、12和20个训练抽头的均方根误差分别降低了68%、40%和9%，表明该方法在训练数据不足的情况下具有更好的性能。仅用4次训练拍，气动系数和斯特罗哈尔数的误差在4%以内。TL-POD-LSTM还能很好地预测非高斯压力区域和瞬时压力极值。对两个串联方缸分别进行了1.25、3、4三种间距比的测试，结果表明该方法能较好地再现下游缸的压力。

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引用次数: 0

Numerical investigation: Undrained capacity of a hybrid anchor under VHMT combined loading in clay 粘土中VHMT复合荷载下混合锚杆不排水能力的数值研究

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-27 DOI: 10.1016/j.oceaneng.2026.124423

Fengwei Yang , Maolin Li , Dengfeng Fu , Yue Yan , Dong Wang

With increasing requirements for the bearing capacity of anchor in floating systems, the concept of hybrid foundations comprising upper gravity mats and lower caisson anchors has been proposed to deliver enhanced load-bearing capabilities. This study employed numerical simulation to analyse the failure mechanisms and holding capacity of the hybrid anchors under vertical uplift, horizontal, bending moment, and torsion (VHMT) loads within clay. By comparing performance with traditional caisson anchors, the study reveals the influence of gravity mats on uniaxial ultimate bearing capacity and combined loading. Results indicate that gravity mats alter the failure mechanism of hybrid anchors, enhancing all uniaxial bearing capacities of the hybrid anchors. Notably, the capacity improvement is significantly greater in homogeneous clay than in normally consolidated clay. Furthermore, the coupling effects between different combined loads undergo changes. Building upon this, this study quantifies the primary failure mechanisms to establish equations for evaluating uniaxial ultimate bearing capacity. The influence of coplanar moments and non-coplanar torsion on the combined holding capacity is further elucidated based on failure envelope analysis. By integrating the proposed uniaxial capacity formula with failure envelopes, a practical framework is established for hybrid anchor design and is demonstrated through representative design cases.

随着对浮式系统中锚的承载能力要求的提高，提出了由上部重力垫和下部沉箱锚组成的混合基础的概念，以提供增强的承载能力。采用数值模拟的方法，分析了粘土中复合锚杆在竖向、水平、弯矩和扭转（VHMT）荷载作用下的破坏机理和承载力。通过与传统沉箱锚杆的性能对比，揭示了重力垫对沉箱锚杆单轴极限承载力和组合荷载的影响。结果表明，重力垫改变了复合锚杆的破坏机制，提高了复合锚杆的单轴承载能力。值得注意的是，均质粘土的承载力提高明显大于正常固结粘土。此外，不同组合荷载之间的耦合效应也发生了变化。在此基础上，本研究量化了主要破坏机制，建立了评估单轴极限承载力的方程。基于失效包络分析，进一步阐明了共面弯矩和非共面扭转对组合持力的影响。将提出的单轴承载力公式与破坏包络线相结合，建立了混合锚杆设计的实用框架，并通过具有代表性的设计实例进行了论证。

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引用次数: 0

Iterative fine-grained decoupling graph neural network for offshore wind turbine remaining useful life prediction 海上风电机组剩余使用寿命预测的迭代细粒度解耦图神经网络

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-27 DOI: 10.1016/j.oceaneng.2026.124411

Linjie Zheng , Yi Qin

The effectiveness of graph neural networks (GNNs) in handling spatial dependencies among sensors has driven their adoption for remaining useful life (RUL) estimation. Yet, present GNN-based approaches directly apply node features to RUL prediction and sensor spatial dependency modeling, neglecting the distinct requirements of these two tasks for node features and failing to achieve task-level feature optimization. Therefore, this paper proposes an iterative fine-grained decoupling graph neural network (IFGDGNN) with adaptive graph pooling for multi-sensor equipment RUL prediction. In IFGDGNN, the proposed node feature iterative decoupling module (NFIDM) employs an iterative pre-decoupling strategy and a decoupling enhancement function, achieving fine-grained decoupling of node features. Subsequently, the decoupled features-based graph update module (DFGUM) is proposed to use the decoupled features separately for spatial dependency modeling and RUL prediction. DFGUM provides task-specific feature optimization directions for NFIDM and employs a coupling network to enable iterative graph updates. Furthermore, a node connectivity-based adaptive graph pooling module is constructed to discard weakly correlated nodes adaptively, optimizing the graph's readout process. The proposed method has not only achieved outstanding performance on two public datasets, but has also been successfully applied to the RUL prediction of the real-world offshore wind turbine, thereby demonstrating its engineering value.

图神经网络（gnn）在处理传感器空间依赖关系方面的有效性推动了它们在剩余使用寿命（RUL）估计中的应用。然而，目前基于gnn的方法直接将节点特征应用于RUL预测和传感器空间依赖建模，忽略了这两个任务对节点特征的不同要求，未能实现任务级特征优化。为此，本文提出了一种具有自适应图池的迭代细粒度解耦图神经网络（IFGDGNN），用于多传感器设备RUL预测。在IFGDGNN中，提出的节点特征迭代解耦模块（NFIDM）采用迭代预解耦策略和解耦增强函数，实现了节点特征的细粒度解耦。随后，提出了基于解耦特征的图更新模块（DFGUM），分别利用解耦特征进行空间依赖建模和规则关系预测。DFGUM为NFIDM提供了特定任务的特征优化方向，并采用耦合网络实现迭代图更新。构建了基于节点连通性的自适应图池模块，自适应丢弃弱相关节点，优化了图的读出过程。该方法不仅在两个公共数据集上取得了优异的性能，而且还成功地应用于实际海上风力机的RUL预测，证明了其工程价值。

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引用次数: 0

Study on energy harvesting performance of flapping hydrofoil with sidewalls and pitching axis 带侧壁和俯仰轴的扑翼水翼能量收集性能研究

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-27 DOI: 10.1016/j.oceaneng.2026.124387

Guanxi Zhang, Weizhong Li, Zhumei Luo, Yandong Bao, Mengqin Yao, Yi Zhao

Based on computational fluid dynamics and three-dimensional overlapping grid technique, the effects of sidewalls, pitching axis configuration, and tandem arrangement on the energy harvesting performance of flapping hydrofoil are systematically investigated. The results indicate that the energy harvesting efficiency gradually increases as the sidewalls distance decreases. And it reaches 40.2 % without pitching axis structure at the distance of 0.004b, which is 10.68 % higher than without sidewalls. With an elliptical pitching axis, the efficiency further improves to 40.65 %. Furthermore, it was found that a staggered arrangement of two-hydrofoil system has a positive effect on the energy harvesting performance. At a horizontal spacing of 1c and a longitudinal spacing of 3c, the impact of a downstream hydrofoil on the energy harvesting efficiency of an upstream hydrofoil is mediated through the disruption of its wake vortex and the creation of a flow blocking effect, the energy harvesting efficiency reaches 38.37 %. The energy harvesting efficiency of the downstream flapping hydrofoil reaches 46.14 %, which is 5.49 % higher than the best-performing single flapping hydrofoil case.

基于计算流体力学和三维重叠网格技术，系统研究了侧壁、俯仰轴构型和串列布置对扑翼水翼能量收集性能的影响。结果表明，随着侧壁距离的减小，能量收集效率逐渐提高。在距离为0.004b处，无俯仰轴结构时，比无侧壁时高10.68%，达到了40.2%。采用椭圆俯仰轴后，效率进一步提高到40.65%。此外，还发现双水翼系统的交错排列对能量收集性能有积极的影响。在水平间距为1c，纵向间距为3c时，下游水翼对上游水翼能量收集效率的影响是通过尾流涡的破坏和流动阻塞效应来调节的，能量收集效率达到38.37%。下游扑翼水翼的能量收集效率达到46.14%，比性能最佳的单扑翼水翼提高了5.49%。

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引用次数: 0

Excitation mechanisms and vibration response of a horizontal elbow in gas-liquid two-phase flow 气液两相流中水平弯头的激励机理及振动响应

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-27 DOI: 10.1016/j.oceaneng.2026.124248

Yitong Fu , Xiang Li , Bolun Ding , Yiran Duan , Lin Ding

Flow-induced vibration caused by gas-liquid two-phase flow in elbow piping systems is a critical concern in energy and process industries, as it can lead to structural fatigue, noise, and operational instability. In this study, gas-liquid two-phase flow in a horizontal downward elbow was simulated using the Volume of Fluid (VOF) method combined with the SST k-ω turbulence model, and the corresponding vibration responses were analyzed through a fluid-structure interaction (FSI) approach. The research examined flow pattern transitions, excitation force fluctuations, and the resulting vibration response and modal switching as different gas-liquid patterns pass through horizontal elbow. The results show that interfacial inertia and momentum differences at the elbow intensify secondary flow and drive downstream pattern transitions. Momentum flux fluctuations caused by interfacial oscillations and slug switching at the bend form the main excitation source, and both excitation amplitude and dominant frequency increasing with superficial velocity. Flow pattern strongly shapes the spatiotemporal vibration characteristics: under stratified-wavy flow, the response is first-mode dominated, with a decaying in-plane peak at the center of the horizontal span, whereas slug flow excites coupled first and third modes and produces sustained, periodic in-plane and out-of-plane vibrations. Overall, the study highlights the crucial roles of flow pattern, superficial velocity and natural modes in governing excitation forces and vibration responses in internal two-phase flow.

弯头管道系统中气液两相流动引起的流动诱发振动是能源和加工工业中一个关键问题，因为它可能导致结构疲劳、噪音和运行不稳定。本研究采用流体体积法（VOF）结合SST k-ω湍流模型模拟了水平向下弯头内气液两相流动，并通过流固耦合（FSI）方法分析了相应的振动响应。该研究考察了不同气液模式通过水平弯头时的流型转换、激振力波动以及由此产生的振动响应和模态切换。结果表明，弯头处的界面惯性和动量差加剧了二次流动，驱动了下游流型的转变。界面振荡和弯道段塞切换引起的动量通量波动是主要激励源，激励幅度和主导频率随表面速度的增加而增加。流动模式强烈地决定了时空振动特征：在分层波流下，响应以第一模态为主，在水平跨度中心有一个衰减的面内峰值，而段塞流激发耦合的第一模态和第三模态，产生持续的、周期性的面内和面外振动。总体而言，该研究强调了流型、表面速度和自然模态在控制两相流内部激励力和振动响应中的关键作用。

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