Ocean Engineering最新文献_第3页

Reliability-based dynamic damage modelling for monopile scour protection under combined waves and currents 波流联合作用下单桩冲刷防护的可靠性动态损伤建模

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-04-30 Epub Date: 2026-02-23 DOI: 10.1016/j.oceaneng.2026.124697

Farshad Homaei , Mohammad Najafzadeh , Sajad Basirian

Scour around monopile foundations presents a critical risk to the structural stability and serviceability of offshore infrastructure. Traditional deterministic models often fail to capture the inherent uncertainties and non-linear dynamics of scour progression and protection system degradation. This study develops a probabilistic framework to evaluate dynamic scour-induced damage functions using three complementary modeling techniques: the Model Tree (MT), Bayesian Regression (BR), and Explanatory Regression (ER). These models incorporate environmental and structural variables, account for epistemic uncertainties, and generate damage estimates expressed via the three-dimensional damage index (S_3D). 160 experiments from six independent sources were used to train and validate the models, incorporating both wave and current effects. The damage evolution is quantified probabilistically across storm durations using a normalized damage function with wave number (N), S_3D/N^0.243. In this study, to evaluate the probability of failure and generate the Exceedance Probability curves, 1,000,000 (one million) iterations of Monte Carlo simulation were used for each of the three models (MT, Bayesian, and Explanatory) and for each wave number scenario (N = 1000, 3000, 5000). This high number was selected to ensure statistical accuracy in the probability estimates, particularly for low-probability damage levels (the tails of the distribution). Results demonstrate that the ER model yields the highest predictive accuracy (Coefficient of Determination [R²] = 0.7534), followed by BR and MT. Importance analysis reveals that U_C/w_s (ratio of the depth-averaged flow velocity [U_C] to sediment particle fall velocity [w_s]), associated with hydrodynamic forcing, is the dominant contributor to scour damage. The probabilistic approach effectively captures the spatial and temporal variability of damage, offering enhanced insight into risk-informed design and maintenance of monopile scour protection systems. By integrating data-driven and interpretable regression methods into a unified reliability framework, the study advances the assessment and forecasting of dynamic scour impacts in offshore environments.

单桩基础周围的冲刷对海上基础设施的结构稳定性和使用能力构成严重威胁。传统的确定性模型往往无法捕捉冲刷过程和保护系统退化的内在不确定性和非线性动力学。本研究开发了一个概率框架，利用三种互补的建模技术：模型树（MT）、贝叶斯回归（BR）和解释回归（ER）来评估动态冲刷引起的损伤函数。这些模型结合了环境和结构变量，考虑了认知上的不确定性，并通过三维损伤指数（S3D）产生损伤估计。来自6个独立来源的160个实验用于训练和验证模型，包括波浪和电流效应。利用波数(N)为S3D/N0.243的归一化损伤函数，对风暴持续时间内的损伤演化进行了概率量化。在本研究中，为了评估故障概率并生成超越概率曲线，对三种模型（MT、贝叶斯和解释性）和每种波数场景（N = 1000、3000、5000）分别使用了1,000,000（一百万）次蒙特卡罗模拟。选择这个高的数字是为了确保概率估计的统计准确性，特别是对于低概率的损害水平（分布的尾部）。结果表明，ER模型的预测精度最高（决定系数[R2] = 0.7534），其次是BR和MT。重要性分析表明，UC/ws（深度平均流速[UC]与泥沙颗粒下降速度[ws]之比）与水动力强迫相关，是冲刷破坏的主要因素。概率方法有效地捕获了破坏的空间和时间变化，为单桩冲刷保护系统的风险设计和维护提供了更好的见解。通过将数据驱动和可解释回归方法整合到统一的可靠性框架中，研究推进了海上环境动态冲刷影响的评估和预测。

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引用次数: 0

Mooring lines structural health monitoring based on floating wind turbine response using an integrated ESAX-ResNet-50 model 基于ESAX-ResNet-50集成模型的浮式风力发电机响应系泊缆结构健康监测

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-04-30 Epub Date: 2026-02-18 DOI: 10.1016/j.oceaneng.2026.124696

Pu Xu , Zhipeng Lin , Ullah Zahid , Jixiang Zheng , Qiming Song , Bo Han

Mooring lines play a crucial role in maintaining the stability and equilibrium of floating offshore wind turbines in harsh marine environments. The failure of a single mooring line can significantly affect the floating wind turbine, resulting in disruption of its operation. Therefore, the structural health monitoring and mooring line damage detection in its early stage is essential for safe operation. The inaccessibility and submergence of mooring lines make its direct and visual monitoring difficult and challenging. Therefore, in this study, an integrated Enhanced Symbolic Aggregation Approximation (ESAX)-ResNet-50 model is developed for indirect monitoring of moorings utilizing the dynamic responses of floating wind turbine. The model symbolically represents the dynamic response using ESAX, followed by bitmap encoding to generate bitmap image of the response. The bitmap images are processed by trained ResNet-50 to classify the health status of mooring lines. For training of the ResNet-50, a semisubmersible floating wind turbine is analyzed under different loading cases with different mooring damaged conditions. The results demonstrate robust capabilities of ESAX-ResNet-50 model in accurate classification of mooring lines health conditions. The model can be effectively used for early damage detection of mooring lines ensuring safe operation of floating wind turbine.

在恶劣的海洋环境中，系泊缆绳对维持漂浮式海上风力发电机的稳定和平衡起着至关重要的作用。单个系泊线的失效会对浮式风力发电机组产生重大影响，导致其运行中断。因此，早期进行结构健康监测和系泊索损伤检测对船舶的安全运行至关重要。系泊线的不可接近性和隐蔽性使其直接可视化监测变得困难和具有挑战性。因此，在本研究中，开发了一种集成的增强符号聚集近似(ESAX)-ResNet-50模型，用于利用浮式风力发电机的动态响应间接监测系泊。该模型使用ESAX符号表示动态响应，然后进行位图编码生成响应的位图图像。使用经过训练的ResNet-50对位图图像进行处理，对系泊线的健康状态进行分类。为了对ResNet-50进行训练，对半潜式浮式风力机在不同载荷情况下、不同系泊损坏情况下进行了分析。结果表明，ESAX-ResNet-50模型在准确分类系泊线健康状况方面具有强大的能力。该模型可有效地用于船舶系泊索的早期损伤检测，保证浮动式风力机的安全运行。

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引用次数: 0

Prototype-scale simulation of key wave parameters and force induced by black tsunamis 黑色海啸关键波浪参数和力的原型尺度模拟

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-04-30 Epub Date: 2026-02-18 DOI: 10.1016/j.oceaneng.2026.124718

Xin Liu, Tomoaki Nakamura, Yong-Hwan Cho, Norimi Mizutani

Black tsunamis, characterized by high concentrations of suspended fine sediments, pose serious threats to marine infrastructure, particularly in enclosed ports and bay areas. This study applies FS3M, a multiphase flow model that incorporates sediment-induced variations in density and viscosity, to numerically investigate black-tsunami impacts. The model is first validated against small-scale flume experiments with different sediment concentrations, showing good agreement in water level, wave pressure, and wave force. Prototype-scale 2D and 3D simulations are then conducted. In the 2D cases, suspended sediment enhances viscous damping under non-breaking conditions, reducing inundation depth and flow velocity. Under breaking conditions, added-mass effects near the quay wall dominate, intensifying the initial surge and inducing vertical stratification. Based on these findings, 3D simulations place structures at three apron positions to examine spatial variability. For non-breaking tsunamis (H = 6–8 m), sediment consistently attenuates horizontal wave forces, indicating that clear-water simulations provide conservative estimates. In contrast, some breaking-wave cases (H = 10 m) exhibit force amplification (ratios 1.02–1.06). These results demonstrate that relying solely on water level may underestimate forces under energetic, sediment-laden conditions, highlighting the need to consider dynamic indicators and emphasizing the importance of including sediment effects in tsunami impact assessments.

黑色海啸的特点是悬浮细沉积物高度集中，对海洋基础设施，特别是封闭港口和海湾地区构成严重威胁。本研究采用了FS3M（一种多相流模型，包含了沉积物引起的密度和粘度变化）来数值研究黑色海啸的影响。该模型首先通过不同泥沙浓度的小规模水槽实验进行验证，在水位、波浪压力和波浪力方面表现出良好的一致性。然后进行了原型尺寸的二维和三维仿真。在二维情况下，悬浮泥沙增强了非破碎条件下的粘性阻尼，降低了淹没深度和流速。在破碎条件下，码头附近的附加质量效应占主导地位，加剧了初始浪涌，诱发了垂直分层。基于这些发现，3D模拟将结构放置在三个停机坪位置以检查空间变异性。对于非破坏性海啸（H = 6-8 m），沉积物持续衰减水平波浪力，这表明清水模拟提供了保守的估计。与此相反，某些破浪情况（H = 10 m）表现出力放大（比率1.02-1.06）。这些结果表明，仅仅依靠水位可能低估了在充满能量和沉积物的条件下的作用力，突出了考虑动态指标的必要性，并强调了在海啸影响评估中包括沉积物效应的重要性。

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引用次数: 0

Experimental and numerical investigations on the hydrodynamics of multi-chambered porous breakwaters with a backwall 多室多孔后壁防波堤水动力特性的实验与数值研究

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-04-30 Epub Date: 2026-02-19 DOI: 10.1016/j.oceaneng.2026.124582

M. Marshal Jins , V. Kumaran , K.G. Vijay , Soumen De

Breakwaters play a vital role in coastal and harbour protection by attenuating incoming waves, with porous types offering unique advantages in energy dissipation and resilience. Owing to the advantages of thin porous barriers, in this study, a breakwater with different thin porous configurations is investigated experimentally and numerically to assess its hydrodynamic performance. A series of experiments is conducted on three porous breakwaters, such as single, dual and triple-chambered designs. The Dual Boundary Element Method (DBEM) effectively models wave scattering by incorporating the quadratic pressure drop boundary condition (QPDC) within the framework of linear wave theory. Further, flow dynamics near porous barriers are analysed using Computational Fluid Dynamics (CFD) simulations, focusing on turbulent kinetic energy (TKE) and velocity vectors. The triple-chambered configuration shows the minimum reflection (K_R = 0.153) at k₀h = 1.53, achieving 38% and 19% greater reflection reduction compared to the single and dual-chambered breakwaters, respectively. This improvement is attributed to enhanced turbulence and vertical flow redirection within the chambers caused by the internal vertical barriers, which promote wave trapping and energy dissipation. A geometric porosity (ε) of 0.3 demonstrates superior energy dissipation, with reflection consistently below 0.125 over the range

k_{0} h = 0.8 - 1.7

, which is a 60% reduction as compared to the 0.2 porosity. Further, the reduced horizontal plate submergence (h₁/h) enhances breakwater performance for longer waves (k₀h < 1.5) without compromising energy dissipation of shorter waves. Overall, the proposed triple-chambered porous breakwater provides multiple advantages for coastal protection when tailored to site-specific wave conditions.

防波堤在海岸和港口保护中起着至关重要的作用，多孔防波堤在能量耗散和弹性方面具有独特的优势。鉴于薄孔屏障的优点，本文对不同薄孔结构的防波堤进行了实验和数值研究，以评估其水动力性能。对单腔、双腔和三腔多孔防波堤进行了一系列试验研究。双边界元法将二次压降边界条件引入线性波理论框架，有效地模拟了波的散射。此外，利用计算流体动力学（CFD）模拟分析了多孔屏障附近的流动动力学，重点分析了湍流动能（TKE）和速度矢量。在k0h = 1.53时，三腔防波堤的反射最小（KR = 0.153），与单腔防波堤和双腔防波堤相比，分别减少了38%和19%的反射。这种改善是由于内部垂直屏障引起的腔室内湍流增强和垂直流动重定向，从而促进了波捕获和能量耗散。几何孔隙度（ε）为0.3表现出优越的能量耗散，在k0h=0.8 ~ 1.7范围内，反射率始终低于0.125，与0.2孔隙度相比降低了60%。此外，降低的水平板淹没度（h1/h）提高了防波堤在较长波浪（k0h <； 1.5）下的性能，而不影响较短波浪的能量耗散。总的来说，拟议的三腔多孔防波堤为海岸保护提供了多种优势，当针对特定的海浪条件进行定制时。

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引用次数: 0

Flow-induced vibration energy harvesting performance enhanced with convergent-acceleration effect 收敛加速效应增强了流激振动能量收集性能

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-04-30 Epub Date: 2026-02-19 DOI: 10.1016/j.oceaneng.2026.124700

Hongjun Sun , Zeyao Yang , Jinxia Li , Zhen Yang

Flow-induced vibration energy harvesting can convert fluid energy into electricity, providing a self-powered solution for micro-power devices. Despite advances, most devices still exhibit high cut-in flow velocity and low efficiency. A new flow-induced vibration energy harvester (FIVEH) based on convergent-acceleration is proposed to enhance performance, especially for lower cut-in flow velocity. The convergent-accelerator profile is optimized, and flow field modulation is validated by wind tunnel test. The Quintic curve-accelerator with 1.67 contraction ratio could reduce the cut-in flow velocity for vortex-induced vibration by 62.3% due to stable fluid acceleration with smooth pressure gradient. The shape of the elastically installed bluff body is optimized, and the different energy harvesting performances at various locations are compared. The results indicate the triangular cylinder at the back of the accelerator has the best performance, with efficiency increased by 508.3% and cut-in flow velocity reduced by 58.3%. Simulation reveals the gradual profile reduction increases pressure differences in both streamwise and spanwise directions, leading to stronger vortex shedding and greater alternating fluid lift on the bluff body, enhancing vibration amplitude and reducing cut-in flow velocity.

流激振动能量收集可以将流体能量转化为电能，为微功率设备提供自供电解决方案。尽管取得了进步，但大多数设备仍然表现出高切割流速和低效率。提出了一种基于收敛加速的新型流激振动能量采集器（FIVEH），以提高其性能，特别是在低切割流速下。对收敛加速型线进行了优化，并通过风洞试验验证了流场调制效果。收缩比为1.67的五次曲线加速器由于流体加速度稳定且压力梯度平滑，可使涡激振动的切割速度降低62.3%。优化了弹性安装钝体的形状，比较了不同位置的能量收集性能。结果表明，采用后置三角形气缸的加速装置效率最高，效率提高508.3%，切割速度降低58.3%。仿真结果表明，剖面的逐渐减小增加了沿流方向和展向方向的压力差，导致钝体上更强的涡脱落和更大的交变流体升力，增强了振动幅值，降低了切入流速。

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引用次数: 0

Sequential multi-objective maintenance optimization with dynamic importance ranking: A case study of subsea transportation system 基于动态重要性排序的顺序多目标维修优化：以海底运输系统为例

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-04-30 Epub Date: 2026-02-20 DOI: 10.1016/j.oceaneng.2026.124672

Yixin Zhao , Baoping Cai , Yiliu Liu , Yanping Zhang , Shibo Wu , Gan Li

Significant failure dependence exists among components of engineering systems, leading to rapid failure propagation and state changes of components. Such compounding dynamics render conventional maintenance strategies prone to inefficiency like over-maintenance, under-maintenance, or maintenance delays. To address the issue of dynamics, this paper proposes a dynamic importance ranking-driven sequential multi-objective maintenance optimization (SMOMO) model. Using a rolling time window approach, the integrated importance of components is dynamically evaluated and ranked based on their real-time states within each window to guide maintenance decision-makings. The window then rolls forward, updating the calculation of long-term expected system cost and availability, based on which a Multi-objective Particle Swarm Optimization (MOPSO) algorithm optimizes maintenance scheduling for cost minimization and availability maximization across the rolling horizon. The proposed methodology is demonstrated and validated using a case study of subsea transportation system. Results illustrate the necessity of dynamic importance evaluation for capturing evolving system status and the effectiveness of the proposed model in optimizing maintenance schedules.

工程系统中构件之间存在着显著的失效依赖关系，导致构件的快速失效传播和状态变化。这种复合动态使得传统的维护策略容易产生低效率，如过度维护、维护不足或维护延迟。为了解决动力学问题，本文提出了一种动态重要性排序驱动的顺序多目标维护优化（SMOMO）模型。采用滚动时间窗方法，根据各部件在每个窗口内的实时状态，对部件的综合重要性进行动态评估和排序，以指导维修决策。然后窗口向前滚动，更新长期预期系统成本和可用性的计算，在此基础上，多目标粒子群优化（MOPSO）算法优化维护计划，以实现成本最小化和可用性最大化。通过海底运输系统的案例研究，验证了所提出的方法。结果表明，动态重要性评估对于捕获不断变化的系统状态是必要的，所提出的模型在优化维修计划方面是有效的。

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引用次数: 0

Effects of flow intensity and vibration–flow alignment angle on riprap protection around a vibrating monopile: An experimental study 流动强度和振流对准角对振动单桩抛石防护效果的实验研究

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-04-30 Epub Date: 2026-02-18 DOI: 10.1016/j.oceaneng.2026.124597

Zihao Tang , Bruce W. Melville , Asaad Y. Shamseldin , Dawei Guan

Riprap is one of the most widely adopted methods for protecting offshore wind turbine monopile foundations against local scour. However, its performance under monopile vibration remains insufficiently understood. This study presents a series of physical model experiments investigating riprap stability and scour development under three flow intensities and three alignment angles between monopile vibration and steady current. The results demonstrate that flow intensity has a direct influence, with higher flow intensities leading to deeper scour. In contrast, the vibration–flow alignment angle exhibits different levels of influence on various scour metrics. In particular, the dynamically enlarged blockage area is shown to play a dominant role in controlling scour depth. Based on the experimental data, empirical equations are proposed to predict multiple scour metrics. The proposed equations demonstrate acceptable accuracy for engineering applications and provide practical guidance for designing riprap protection around vibrating monopile foundations. These findings contribute to improving the reliability of scour protection strategies for offshore wind energy infrastructure.

抛石是保护海上风力发电机单桩基础免受局部冲刷的最广泛采用的方法之一。然而，对其在单桩振动作用下的性能还不够了解。本文通过一系列物理模型实验，研究了三种水流强度和三种单桩振动与稳态电流的定向角度下抛石的稳定性和冲刷发展情况。结果表明，水流强度对冲刷有直接影响，水流强度越大，冲刷程度越深。相比之下，振动流向角对各种冲刷指标的影响程度不同。特别是，动态扩大的堵塞面积在控制冲刷深度方面起主导作用。在实验数据的基础上，提出了预测多个冲刷指标的经验方程。所提出的方程在工程应用中具有良好的精度，为振动单桩基础抛石防护设计提供了实用的指导。这些发现有助于提高海上风能基础设施冲刷保护策略的可靠性。

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引用次数: 0

Numerical research on the impact of built-in rectangular poles on the dynamic characteristics of rectangular liquid tanks 矩形内嵌杆对矩形液罐动力特性影响的数值研究

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-04-30 Epub Date: 2026-02-21 DOI: 10.1016/j.oceaneng.2026.124728

Xin He , Chao Li , Lingwei Chen , Gang Hu , Jinping Ou

Tuned liquid damper (TLD) mitigates excessive vibration responses of offshore platform structures by utilizing liquid oscillation within a tank. However, the conventional pure-water TLD exhibits limited energy dissipation capacity, which is often insufficient to meet structural vibration control requirements. To enhance the damping performance of TLD, the incorporation of internal obstruction devices is necessary. Moreover, when applied to offshore platform structures, the large dimensions of the TLD tank and the significant liquid sloshing forces require robust internal supporting components to ensure safe and stable operation. In this study, an innovative TLD configuration with built-in rectangular poles is proposed. First, based on computational fluid dynamics (CFD), the two-phase flow solver in OpenFOAM is improved by coupling the level set and volume of fluid (VOF) algorithms (CLS-VOF). This improvement effectively suppresses spurious flows and enhances the accuracy of free-surface capturing. The numerical simulation results show good agreement with experimental data, demonstrating the reliability and accuracy of the proposed numerical model. Subsequently, the effects of critical parameters, including the liquid filling level, number of poles, pole installation position, pole blockage ratio, and excitation amplitude, on the nonlinear sloshing behavior of the internal liquid are systematically investigated, establishing a fundamental database of the dynamic characteristics of the rectangular liquid tank with poles. Then, an equivalent mechanical model is developed using the particle swarm optimization (PSO) algorithm to estimate the sloshing frequency and damping performance of the rectangular liquid tank with poles. The theoretical predictions are compared with numerical simulation results to validate the accuracy of the proposed model. The equivalent mechanical model enables rapid and reliable determination of the dynamic parameters of the TLD, providing effective support for the preliminary design and optimization of TLD in engineering applications.

调谐液体阻尼器（TLD）通过利用储罐内的液体振动来减轻海洋平台结构的过度振动响应。然而，传统的纯水TLD耗能能力有限，往往不能满足结构振动控制的要求。为了提高TLD的阻尼性能，必须加入内阻装置。此外，当应用于海洋平台结构时，TLD储罐的大尺寸和显著的液体晃动力需要坚固的内部支撑部件来确保安全稳定运行。在这项研究中，提出了一种具有内置矩形极点的创新TLD配置。首先，基于计算流体力学（CFD），通过耦合水平集和流体体积（VOF）算法（CLS-VOF）对OpenFOAM中的两相流求解器进行改进。这种改进有效地抑制了杂散流，提高了自由表面捕获的精度。数值模拟结果与实验数据吻合较好，验证了所建数值模型的可靠性和准确性。随后，系统研究了液体填充液位、极数、极安装位置、极堵塞比、激励幅值等关键参数对内部液体非线性晃动行为的影响，建立了矩形极液罐动态特性基础数据库。然后，利用粒子群优化（PSO）算法建立了等效力学模型，对带杆矩形液罐的晃动频率和阻尼性能进行了估计。将理论预测结果与数值模拟结果进行了比较，验证了模型的准确性。该等效力学模型能够快速、可靠地确定TLD的动态参数，为TLD在工程应用中的初步设计和优化提供有效支持。

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引用次数: 0

A CFD-informed machine learning framework for generalized ship resistance prediction under wind and wave conditions 用于风浪条件下船舶阻力预测的cfd信息机器学习框架

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-04-30 Epub Date: 2026-02-21 DOI: 10.1016/j.oceaneng.2026.124759

Yangyang Zhai, Xuefeng Yang, Shengli Chen

Accurate prediction of ship fuel consumption is critical for optimizing operations and reducing emissions, yet remains challenging for most of vessels lacking high-precision sensor data. To address this, we propose a novel hybrid framework that integrates computational fluid dynamics (CFD) and machine learning to achieve predictions without relying on extensive sensor measurements. Our approach begins with fusing multi-source data (AIS, meteorological, and voyage reports) to reconstruct hourly operational profiles. A clustering-based technique is then employed to identify a limited set of representative typical operating conditions from the overall conditions. High-fidelity CFD is used to compute ship resistance at these selected typical conditions (7-60 types), generating a high-quality dataset. Finally, a suite of machine learning models (including MPR, RR, LASSO, RF, XGBoost, and ANN) are trained and evaluated on this dataset to generalize resistance predictions across the entire operational conditions. In a case study of a 3600 TEU containership, our framework achieves a mean absolute error of below 0.86 in resistance prediction, demonstrating comparable accuracy to sensor-based models. This work provides an effective, scalable, and accurate alternative for ship fuel consumption prediction, with significant potential for global application.

准确预测船舶燃油消耗对于优化运营和减少排放至关重要，但对于大多数缺乏高精度传感器数据的船舶来说，这仍然是一项挑战。为了解决这个问题，我们提出了一个新的混合框架，它集成了计算流体动力学（CFD）和机器学习，以实现预测，而不依赖于广泛的传感器测量。我们的方法首先是融合多源数据（AIS、气象和航次报告）来重建每小时的运营概况。然后采用基于聚类的技术从总体条件中识别出一组有限的具有代表性的典型操作条件。采用高保真CFD计算这些选定的典型工况（7-60种）下的船舶阻力，生成高质量的数据集。最后，在该数据集上对一套机器学习模型（包括MPR、RR、LASSO、RF、XGBoost和ANN）进行训练和评估，以推广整个操作条件下的阻力预测。在3600 TEU集装箱船的案例研究中，我们的框架在阻力预测方面的平均绝对误差低于0.86，证明了与基于传感器的模型相当的准确性。这项工作为船舶燃料消耗预测提供了一种有效、可扩展和准确的替代方案，具有巨大的全球应用潜力。

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引用次数: 0

An analytical framework for torsional dynamic response of floating piles in viscoelastic unsaturated transversely isotropic soils 粘弹性非饱和横向各向同性土中浮桩扭转动力响应的分析框架

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-04-30 Epub Date: 2026-02-23 DOI: 10.1016/j.oceaneng.2026.124783

Wenjie Ma , Jiayi Gao , Xu Wang , Bolin Wang , Eng-Choon Leong , Changdan Wang , Yalong Zhou

This study develops an analytical framework to assess the torsional response of floating piles by considering the fractional viscoelasticity and transverse isotropy of unsaturated soils, addressing the critical yet overlooked influence of the finite-thic kness soil layer between the pile tip and bedrock. By introducing a fictitious unsaturated soil pile (FUSP) methodology, the pile is virtually extended to bedrock, with the FUSP inheriting the fractional-order viscoelastic properties of the surrounding soil. The governing equations integrate three-phase interactions, transverse isotropy, and fractional calculus-based viscoelasticity, enabling unified modeling of both floating and end-bearing piles. The derivation process involves the techniques of separation of variables and eigenfunction expansion, leading to closed-form solutions for the frequency-domain torsional impedance, while semi-analytical time-domain responses under semi-sine pulse excitation are obtained via inverse Fourier transformation and convolution theory. Parametric analyses demonstrate the sensitivity of pile head impedance and twist angle to FUSP and pile length, saturation, transverse isotropy ratios, fractional derivative order, and viscoelastic relaxation times.

本研究通过考虑非饱和土的分数粘弹性和横向各向同性，建立了一个分析框架来评估浮动桩的扭转响应，解决了桩端与基岩之间有限厚度土层的关键但被忽视的影响。通过引入一种虚拟非饱和土桩（FUSP）方法，将桩虚拟地扩展到基岩，FUSP继承了周围土体的分数阶粘弹性特性。控制方程集成了三相相互作用、横向各向同性和分数阶基于微积分的粘弹性，从而实现了浮动桩和端承桩的统一建模。推导过程涉及变量分离和特征函数展开技术，得到频域扭转阻抗的封闭解，而半正弦脉冲激励下的半解析时域响应则通过傅里叶反变换和卷积理论得到。参数分析表明，桩顶阻抗和扭转角对FUSP和桩长、饱和度、横向各向同性比、分数阶导数阶数和粘弹性松弛时间的敏感性。

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