Applied Ocean Research最新文献

{"title":"Reduced Order Modeling (ROM) based method for the two-dimensional water exit problem using snapshot Proper Orthogonal Decomposition (POD) and CFD simulations","authors":"Xupeng Sui ,&nbsp;Kamal Djidjeli ,&nbsp;Zhe Sun ,&nbsp;Jing Tang Xing","doi":"10.1016/j.apor.2025.104697","DOIUrl":"10.1016/j.apor.2025.104697","url":null,"abstract":"<div><div>In this paper, the concepts of snapshot Proper Orthogonal Decomposition (POD) and Reduced Order Modeling (ROM) are combined (referred to the POD-ROM method) to solve the two-dimensional (2D) water exit problem. Attention is paid to the pressure distribution along the wetted surface of the body. Computational Fluid Dynamics (CFD) simulations are employed to obtain high-fidelity data on pressure distribution. After applying snapshot POD, it is found that two POD basis modes for the wedge model and three modes for the ship section model are adequate to capture dynamic features of the pressure distribution without losing too much detail. It can also be observed that neither the body motion state nor the initial immersion condition influences all POD functions of the wedge model, but the temporal POD functions of the ship section model are significantly dependent on the initial immersion height. A group of empirical formulae is provided to deal with this issue. The validity and reliability of our POD-ROM method are assessed by investigating water exit cases with both constant and time-varying body accelerations. In this context, after deriving POD functions of any given 2D body from a single CFD simulation, predictions of the pressure distribution along the body can be facilitated for further water exit cases.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"161 ","pages":"Article 104697"},"PeriodicalIF":4.3,"publicationDate":"2025-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144580303","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":"A full wind bivariate bias correction method","authors":"Sebastian Solari,&nbsp;Rodrigo Alonso","doi":"10.1016/j.apor.2025.104686","DOIUrl":"10.1016/j.apor.2025.104686","url":null,"abstract":"<div><div>This study proposes a non-parametric bivariate bias correction method for wind direction and speed, capable of correcting the full bivariate distribution of these variables, not just their marginal distributions. The proposed method is applied to a case study in the inner Río de la Plata estuary, where its performance is evaluated and compared with other commonly used approaches for bias correction in coastal and ocean engineering. Additionally, the impact of wind bias correction on modeling wave generation and propagation within the inner estuary is analyzed. The results demonstrate that the proposed method performs exceptionally well in bivariate wind bias correction, outperforming the other methods examined. However, this improvement does not lead to a better performance of the wave model, although this latter result may be attributed to the short duration of the available wave data series.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"161 ","pages":"Article 104686"},"PeriodicalIF":4.3,"publicationDate":"2025-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144571792","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":"High speed planing craft dynamics in irregular waves: Safety improvement using interceptor systems","authors":"Fatemeh Roshan ,&nbsp;Rasul Niazmand Bilandi ,&nbsp;Fabio De Luca ,&nbsp;Simone Mancini ,&nbsp;Pentti Kujala ,&nbsp;Abbas Dashtimanesh","doi":"10.1016/j.apor.2025.104692","DOIUrl":"10.1016/j.apor.2025.104692","url":null,"abstract":"<div><div>This study investigates the potential for improving the dynamic performance and human safety of High-Speed Planing Craft (HSPC) in irregular head waves through the implementation of a Transom Interceptor System (TIS) and a Double Interceptor System (DIS). Experimental tests measure hull resistance, heave and pitch motions, and vertical accelerations in semi-planing, transient, and planing modes. The recorded data for the bare hull, the hull equipped with TIS in transient mode, and the hull equipped with TIS and DIS in planing mode are compared to evaluate the interceptor performance in improving the dynamics of HSPC. Additionally, the crew safety exposed to vertical acceleration is evaluated according to the ISO 2631–1 (1997), ISO 2631–5 (2004), and EU Directive 2002/44/EC (2002). The results indicate that TIS effectively enhances dynamic performance in transient and planing modes as well as human safety and comfort by reducing moderate vertical acceleration. However, in transient mode, TIS may amplify impact shocks, increasing the possibility of adverse health effects. Moreover, the DIS increases hull motions, vertical acceleration, and the potential for health and comfort risks in planing mode. These findings emphasize the potential of TIS in enhancing HSPC dynamics and safety, while it is crucial to optimize interceptor configurations based on operational speeds.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"161 ","pages":"Article 104692"},"PeriodicalIF":4.3,"publicationDate":"2025-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144571791","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":"Exploring bluff body geometries for enhanced energy harvesting from flow-induced vibrations using machine learning","authors":"Shohreh Jalali,&nbsp;Ebrahim Barati,&nbsp;Amir Sarviha","doi":"10.1016/j.apor.2025.104688","DOIUrl":"10.1016/j.apor.2025.104688","url":null,"abstract":"<div><div>This study investigates energy harvesting from flow-induced vibrations using various bluff body geometries, combining experimental techniques and machine learning for performance analysis. An electromagnetic energy harvester, featuring a permanent magnet in motion within a coil and coupled to a flexible diaphragm, was used to extract energy from vortex-induced vibrations in a flow channel. The study expands prior research by evaluating Circle, Square (at 0, 22.5, and 45 degrees), Rectangle, Trapezoid (small and large cases), and Diamond geometries across Reynolds numbers (<em>Re</em> = 3000, 4000, and 5000). A key innovation lies in applying six advanced machine learning models—Decision Tree, Random Forest, XGBoost, Gradient Boosting, CatBoost, and LightGBM—for voltage prediction, with a novel Weighted Ensemble method demonstrating exceptional accuracy (MAE: 0.1540, MSE: 0.0459, RMSE: 0.2141, R²: 0.9336). Experimental results revealed that Diamond and Circle geometries achieved superior energy outputs of 3.8 and 2.6 units at <em>Re</em> = 5000, while Trapezoid (large case) and Square at 45 degrees performed optimally at <em>Re</em> = 4000. This work enhances understanding of flow-induced energy harvesting, offering comprehensive insights into optimizing harvester designs through a synergy of experimental validation and machine learning predictions.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"161 ","pages":"Article 104688"},"PeriodicalIF":4.3,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144548509","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 wave spectrum representation on power production estimations from point absorbers","authors":"Matías Alday,&nbsp;Vaibhav Raghavan,&nbsp;George Lavidas","doi":"10.1016/j.apor.2025.104626","DOIUrl":"10.1016/j.apor.2025.104626","url":null,"abstract":"<div><div>This study presents a first long term (30 years) assessment to quantify the effects of both, the wave spectrum representation, and occurrences of multi-modal sea states, on power production estimations from a point-absorber Wave Energy Converter (WEC). Analysis in 3 different offshore locations (Portugal, Ireland and The Netherlands) is included to ensure robustness of results. In general, traditional methods based on the use of the JONSWAP spectrum, with an adequate gamma shape value, can lead to mean overestimation in yearly power production <span><math><mrow><mo>&gt;</mo><mn>12</mn><mtext>%</mtext></mrow></math></span> when compared to reference hindcast spectral data. This can be partially reduced when capping is applied to power production, but still can be close to <span><math><mrow><mn>10</mn><mtext>%</mtext></mrow></math></span>. An alternative method is proposed to modulate the JONSWAP spectrum at each time step which helps to reduce differences, but leads to slight yearly underestimations (−2.5 to −5% in average). Although in all analyzed sites the occurrences of multi-modal spectra is <span><math><mrow><mo>&gt;</mo><mn>30</mn><mtext>%</mtext></mrow></math></span>, contribution to errors due to misrepresentation of these sea states are estimated to be of about <span><math><mrow><mn>2</mn><mo>.</mo><mn>5</mn><mtext>%</mtext></mrow></math></span>. These findings provide valuable insights on the uncertainties introduced in power production estimations, related to wave conditions characterization, that can have important economic impact when planning for large scale deployments.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"161 ","pages":"Article 104626"},"PeriodicalIF":4.3,"publicationDate":"2025-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144522716","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":"Separating swell from mixed waves around island through wave action balance modeling","authors":"Zongbing Yu ,&nbsp;Yuxi Wu ,&nbsp;Li Zou ,&nbsp;Zhen Wang ,&nbsp;Guoqing Jin ,&nbsp;Liangyu Liu","doi":"10.1016/j.apor.2025.104687","DOIUrl":"10.1016/j.apor.2025.104687","url":null,"abstract":"<div><div>Wind seas and swells typically co-occur around islands, resulting in a wave spectrum with a frequency characterized by double or multiple peaks. Separating the wave energies of wind seas and swells is crucial for accurately estimating the wave loads exerted on offshore structures around islands. This study presents a novel method for accurately separating wind sea and swell, considering the effects of wind fields and topographic features around the island on the wave spectrum. The fetch around the island was determined by the wave conditions and wind sea growth curve with respect to wind velocity, and the local wind field was then vanished and the wave action balance model executed again to obtain the swell component. The remaining energy in the wave spectrum was regarded as wind sea. The proposed method was validated using the observed wave conditions during Typhoon Sarika in the Atoll area of the South China Sea. The method successfully separated the wind sea and swell, and both exhibit wave spectra, which differ from the separation frequency obtained by traditional methods. Furthermore, both the one-dimensional and directional spectra demonstrated excellent performance.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"161 ","pages":"Article 104687"},"PeriodicalIF":4.3,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144522714","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":"Design and analysis of wall-climbing robot with passive adaptive parallel mechanism","authors":"Pei Jia ,&nbsp;Tianyu Zheng ,&nbsp;Manhong Li ,&nbsp;Minglu Zhang ,&nbsp;Zhexuan Huang","doi":"10.1016/j.apor.2025.104690","DOIUrl":"10.1016/j.apor.2025.104690","url":null,"abstract":"<div><div>Wall-climbing robots (WCRs) are widely used for inspecting and maintaining large ship facades to ensure structural safety and reliable performance. However, most existing WCRs hardly pass through facades with variable curvature and dense obstacles because of their rigid mechanisms with limited degrees of freedom and inflexible motion. We propose an omnidirectional mobile WCR integrating a passive adaptive parallel mechanism and omnidirectional steering hauling mechanism. Using the atlas method design criteria, a passive adaptive parallel mechanism combining rotational and translational units was developed, compensating for height differences and fitting angles during wheel rolling on irregular surfaces. By mounting the omnidirectional steering hauling mechanism on the parallel mechanism, specific motion modes enable the robot to flexibly adjust the wheel directions for navigating constrained environments. Considering the adhesive force direction change with curvature, an index representing the varying angle allows us to establish mechanical equilibrium relations and calculate the minimum magnetic force required to ensure stable adhesion. Circuit analysis of the permanent magnet module yielded optimal parameters to enhance adhesion efficiency and stability. Experiments demonstrate that the developed robot can adhere stably and move flexibly on facades with variable curvature and localized obstacles, showing promise for ship inspection and maintenance.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"161 ","pages":"Article 104690"},"PeriodicalIF":4.3,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144522715","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":"An analysis on OpenMetBuoy-v2021 drifter in-situ data and Lagrangian trajectory simulations in the Agulhas Current System","authors":"Bente Moerman ,&nbsp;Øyvind Breivik ,&nbsp;Lars R. Hole ,&nbsp;Gaute Hope ,&nbsp;Johnny A. Johannessen ,&nbsp;Jean Rabault","doi":"10.1016/j.apor.2025.104649","DOIUrl":"10.1016/j.apor.2025.104649","url":null,"abstract":"<div><div>The primary objective of this study is to perform a sensitivity analysis of Lagrangian trajectory models. Trajectory simulations have been compared to six OpenMetBuoy-v2021 drifter trajectories in the Agulhas Current System (Jan–Mar 2023). Three different Lagrangian trajectory simulations have been assessed: (1) two offline Lagrangian tracking tools, OpenDrift and Parcels, (2) three Eulerian ocean surface current products, HYCOM, Mercator and Globcurrent, and (3) the addition of wind and/or wave forcing parameterizations. The latter has also been evaluated by strong ocean current, high wind speed and Stokes drift regimes.</div><div>Firstly, using the same time stepping scheme and linear interpolation methods, the different Lagrangian simulators OpenDrift and Parcels, performed identically. Secondly, the Globcurrent product showed the highest mean skill of the three ocean current products, although it underestimated the speed for strong ocean currents due to its spatial resolution. The HYCOM and Mercator model simulations showed, respectively, 40% and 15% lower skill than the Globcurrent simulations. Finally, the addition of the Stokes drift and a wind drift factor (WDF), improved the Lagrangian simulation performance in skill and speed, especially in high wind (<span><math><mo>&gt;</mo></math></span>10 m/s) and/or Stokes drift regimes (<span><math><mo>&gt;</mo></math></span>0.15 m/s). The optimal WDF for the OpenMetBuoy-v2021 is found to be 1.8% and 2.3% for simulations including and excluding Stokes drift forcing respectively. To further improve the incorporation of Stokes drift and direct wind drag on the trajectory simulations, a more physically based solution is advised as there are still numerous wind and wave related processes that remain unresolved, like wave–current interactions and vertical shear.</div><div>To statistically strengthen the conclusions from this research, incorporating additional observed drifter trajectories would be highly favourable.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"161 ","pages":"Article 104649"},"PeriodicalIF":4.3,"publicationDate":"2025-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144514086","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 analysis of offshore monopile foundations in layered clay","authors":"Ali Khezri ,&nbsp;Hongbae Park ,&nbsp;Daeyong Lee","doi":"10.1016/j.apor.2025.104685","DOIUrl":"10.1016/j.apor.2025.104685","url":null,"abstract":"<div><div>Monopiles are often embedded in layered soil profiles, where stratification significantly influences their lateral load response. However, much of the existing literature and proposed methodologies predominately focus on uniform soil profiles which is far from the reality. To address this, three-dimensional (3D) finite-element (FE) analyses were conducted on laterally loaded monopiles with varying slenderness ratios in different clay layering configurations. Three general profiles were examined: a two-layer clay profile, a soft interlayer within a stiff layer, and a three-layer clay profile. By systematically varying layer thickness and position, a broad range of scenarios was analyzed, leading to quantitative design recommendations for monopiles with different slenderness ratios. Additionally, two methods are proposed for estimating monopile capacity in layered soils, based on its capacity in the corresponding homogeneous soil profile. The first, a predictive equation, is more accurate and convenient for two-layer profiles but becomes complex for multi-layered systems. To overcome this, an alternative approach—the <em>layer-coefficient method</em>—was developed. This method differentiates lateral capacity ratio (LCR) curves to generate layer coefficient graphs, providing insight into each layer’s influence on lateral capacity. Compared to the equation-based method, the <em>layer-coefficient</em> approach is more intuitive, offers clearer design guidance, and is more convenient for multilayered soil profiles.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"161 ","pages":"Article 104685"},"PeriodicalIF":4.3,"publicationDate":"2025-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144514085","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":"Interaction of water surface waves with periodic and quasiperiodic cylinder arrays","authors":"Joseph A. Smerdon ,&nbsp;Sam Coates ,&nbsp;Bogdan J. Matuszewski ,&nbsp;Benedict D. Rogers","doi":"10.1016/j.apor.2025.104673","DOIUrl":"10.1016/j.apor.2025.104673","url":null,"abstract":"<div><div>Inspired by transformation optics and photonic crystals, this paper presents a computational investigation into the interaction between water surface waves and array waveguides of cylinders with multiple previously unexplored lattice geometries, including, for the first time, quasiperiodic geometries. Extending beyond conventional square and hexagonal periodic arrays, transformation optics has opened up entirely new opportunities to investigate water wave propagation through arrays based on quasiperiodic lattices, and quasiperiodically arranged vacancy defects. Using the linear potential flow open-source code Capytaine, missing element and <span><math><mi>τ</mi></math></span>-scaled Fibonacci square lattices, the Penrose lattice, hexagonal <span><math><msub><mrow><mi>H</mi></mrow><mrow><mn>00</mn></mrow></msub></math></span> lattice and Ammann–Beenker lattice are investigated. The existence of band gaps for all arrays is observed. A hexagonal lattice with vacancy defects transmits the least energy. Bragg diffraction consistent with azimuthal rotational symmetry is observed from all arrays. Bragg resonance causes reflection from arrays, resulting in multiple Bloch band gaps. Away from Bragg resonance, waves will distort significantly to achieve periodic relationships with arrays, supporting transformation-based waveguides. The possible uses include adaptation to more versatile waveguides with applications such as offshore renewable energy and coastal defence.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"161 ","pages":"Article 104673"},"PeriodicalIF":4.3,"publicationDate":"2025-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144510998","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}