Ocean Engineering最新文献

{"title":"Vulnerability analysis of offshore wind turbines considering the correlation of wind and waves","authors":"Tao Wu ,&nbsp;Bo Chen ,&nbsp;Ying Sun","doi":"10.1016/j.oceaneng.2026.124636","DOIUrl":"10.1016/j.oceaneng.2026.124636","url":null,"abstract":"<div><div>Vulnerability analysis, by considering load and structural uncertainties, provides an approach to reducing costs through optimized structural performance utilization. Addressing limitations in existing research regarding wind-wave correlation and performance level, this manuscript employs measured wind-wave data to estimate coherence functions using a 4th-order bandpass filter and 12th-order vector autoregressive. By analyzing wind-wave coherence under different sea states, a coherence function model is established and validated. OpenFAST is then utilized to generate wind-wave load time histories incorporating wind-wave correlations. An OWT numerical model is established in ANSYS to investigate dynamic responses, involving platform pitching, nacelle acceleration, and stress of tower and blade. A unified damage evaluation indicator and a three-stage performance level division standard for OWTs are proposed accordingly. The study subsequently conducts vulnerability analysis considering both wind-wave correlations and three-stage performance level. The study demonstrate that the proposed division standard effectively distinguishes between slight, moderate, and severe damage of OWT, with significant probability variations under identical load. This provides a reference for the design to fully utilize performance of OWTs. Notably, probabilities of achieving each performance level increase when wind-wave correlations are considered compared to uncorrelated cases, underscoring the necessity of incorporating wind-wave correlation in performance-based OWT design.</div></div>","PeriodicalId":19403,"journal":{"name":"Ocean Engineering","volume":"353 ","pages":"Article 124636"},"PeriodicalIF":5.5,"publicationDate":"2026-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386347","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}

{"title":"Novel algorithm for the calibration of DVL in underwater integrated navigation system","authors":"Haixu Zhang ,&nbsp;Chong Li ,&nbsp;Tao Zhang ,&nbsp;Guangcai Wang ,&nbsp;Di Wang","doi":"10.1016/j.oceaneng.2026.124676","DOIUrl":"10.1016/j.oceaneng.2026.124676","url":null,"abstract":"<div><div>Calibration plays a critical role in enhancing the performance of underwater integrated navigation systems. Widely used calibration algorithms based on filtering theory often neglect higher-order disturbance terms in the expansion of the target equation and commonly assume misalignment angles as small quantities for approximate calculations. In engineering applications, when misalignment angles cannot be considered negligible, the resulting computational errors become significant.</div><div>To address this problem, we propose a novel Local Area Segmentation (LAS) optimization algorithm for Doppler Velocity Log (DVL) error calibration that incorporates all error terms. Building upon the commonly used single-valued scale factor calibration model, we develop extended calibration models to include three-axis scale factors and four-beam scale factors. All three models are utilized to validate the superiority of the proposed algorithm. Experimental results demonstrate that the proposed algorithm achieves higher estimation accuracy, significantly improving DVL calibration precision.</div></div>","PeriodicalId":19403,"journal":{"name":"Ocean Engineering","volume":"353 ","pages":"Article 124676"},"PeriodicalIF":5.5,"publicationDate":"2026-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147387096","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}

{"title":"Reliability-based dynamic damage modelling for monopile scour protection under combined waves and currents","authors":"Farshad Homaei ,&nbsp;Mohammad Najafzadeh ,&nbsp;Sajad Basirian","doi":"10.1016/j.oceaneng.2026.124697","DOIUrl":"10.1016/j.oceaneng.2026.124697","url":null,"abstract":"<div><div>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.</div></div>","PeriodicalId":19403,"journal":{"name":"Ocean Engineering","volume":"353 ","pages":"Article 124697"},"PeriodicalIF":5.5,"publicationDate":"2026-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147387103","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}

{"title":"Mooring lines structural health monitoring based on floating wind turbine response using an integrated ESAX-ResNet-50 model","authors":"Pu Xu ,&nbsp;Zhipeng Lin ,&nbsp;Ullah Zahid ,&nbsp;Jixiang Zheng ,&nbsp;Qiming Song ,&nbsp;Bo Han","doi":"10.1016/j.oceaneng.2026.124696","DOIUrl":"10.1016/j.oceaneng.2026.124696","url":null,"abstract":"<div><div>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.</div></div>","PeriodicalId":19403,"journal":{"name":"Ocean Engineering","volume":"353 ","pages":"Article 124696"},"PeriodicalIF":5.5,"publicationDate":"2026-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386431","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}

{"title":"Prototype-scale simulation of key wave parameters and force induced by black tsunamis","authors":"Xin Liu,&nbsp;Tomoaki Nakamura,&nbsp;Yong-Hwan Cho,&nbsp;Norimi Mizutani","doi":"10.1016/j.oceaneng.2026.124718","DOIUrl":"10.1016/j.oceaneng.2026.124718","url":null,"abstract":"<div><div>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 (<em>H</em> = 6–8 m), sediment consistently attenuates horizontal wave forces, indicating that clear-water simulations provide conservative estimates. In contrast, some breaking-wave cases (<em>H</em> = 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.</div></div>","PeriodicalId":19403,"journal":{"name":"Ocean Engineering","volume":"353 ","pages":"Article 124718"},"PeriodicalIF":5.5,"publicationDate":"2026-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386559","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}

{"title":"Experimental and numerical investigations on the hydrodynamics of multi-chambered porous breakwaters with a backwall","authors":"M. Marshal Jins ,&nbsp;V. Kumaran ,&nbsp;K.G. Vijay ,&nbsp;Soumen De","doi":"10.1016/j.oceaneng.2026.124582","DOIUrl":"10.1016/j.oceaneng.2026.124582","url":null,"abstract":"<div><div>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 (<em>K_R</em> = 0.153) at <em>k</em>₀<em>h</em> = 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 <span><math><mrow><msub><mi>k</mi><mn>0</mn></msub><mi>h</mi><mo>=</mo><mn>0.8</mn><mo>−</mo><mn>1.7</mn></mrow></math></span>, which is a 60% reduction as compared to the 0.2 porosity. Further, the reduced horizontal plate submergence (<em>h</em>₁/<em>h</em>) enhances breakwater performance for longer waves (<em>k</em>₀<em>h</em> &lt; 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.</div></div>","PeriodicalId":19403,"journal":{"name":"Ocean Engineering","volume":"353 ","pages":"Article 124582"},"PeriodicalIF":5.5,"publicationDate":"2026-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386704","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}

{"title":"Flow-induced vibration energy harvesting performance enhanced with convergent-acceleration effect","authors":"Hongjun Sun ,&nbsp;Zeyao Yang ,&nbsp;Jinxia Li ,&nbsp;Zhen Yang","doi":"10.1016/j.oceaneng.2026.124700","DOIUrl":"10.1016/j.oceaneng.2026.124700","url":null,"abstract":"<div><div>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.</div></div>","PeriodicalId":19403,"journal":{"name":"Ocean Engineering","volume":"353 ","pages":"Article 124700"},"PeriodicalIF":5.5,"publicationDate":"2026-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386768","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}

{"title":"Sequential multi-objective maintenance optimization with dynamic importance ranking: A case study of subsea transportation system","authors":"Yixin Zhao ,&nbsp;Baoping Cai ,&nbsp;Yiliu Liu ,&nbsp;Yanping Zhang ,&nbsp;Shibo Wu ,&nbsp;Gan Li","doi":"10.1016/j.oceaneng.2026.124672","DOIUrl":"10.1016/j.oceaneng.2026.124672","url":null,"abstract":"<div><div>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.</div></div>","PeriodicalId":19403,"journal":{"name":"Ocean Engineering","volume":"353 ","pages":"Article 124672"},"PeriodicalIF":5.5,"publicationDate":"2026-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147387254","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}

{"title":"Effects of flow intensity and vibration–flow alignment angle on riprap protection around a vibrating monopile: An experimental study","authors":"Zihao Tang ,&nbsp;Bruce W. Melville ,&nbsp;Asaad Y. Shamseldin ,&nbsp;Dawei Guan","doi":"10.1016/j.oceaneng.2026.124597","DOIUrl":"10.1016/j.oceaneng.2026.124597","url":null,"abstract":"<div><div>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.</div></div>","PeriodicalId":19403,"journal":{"name":"Ocean Engineering","volume":"353 ","pages":"Article 124597"},"PeriodicalIF":5.5,"publicationDate":"2026-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386346","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}

{"title":"Numerical research on the impact of built-in rectangular poles on the dynamic characteristics of rectangular liquid tanks","authors":"Xin He ,&nbsp;Chao Li ,&nbsp;Lingwei Chen ,&nbsp;Gang Hu ,&nbsp;Jinping Ou","doi":"10.1016/j.oceaneng.2026.124728","DOIUrl":"10.1016/j.oceaneng.2026.124728","url":null,"abstract":"<div><div>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.</div></div>","PeriodicalId":19403,"journal":{"name":"Ocean Engineering","volume":"353 ","pages":"Article 124728"},"PeriodicalIF":5.5,"publicationDate":"2026-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386351","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}