Ocean Engineering最新文献

{"title":"A novel arithmetic operation function utilizing height of interval type-2 fuzzy sets to express risk preference: case study of remotely controlled autonomous ship","authors":"Cunlong Fan ,&nbsp;Yongquan Chen ,&nbsp;Shiqi Fan ,&nbsp;Shanshan Fu ,&nbsp;Chengpeng Wan ,&nbsp;Yongtao Xi ,&nbsp;Zaili Yang","doi":"10.1016/j.oceaneng.2025.122940","DOIUrl":"10.1016/j.oceaneng.2025.122940","url":null,"abstract":"<div><div>Risk analysis for maritime emerging technology relies on subjective data derived from the knowledge, experiences, and individual characteristics of seafarers or experts. Risk preference is a key indicator in maritime emergencies, playing a significant role in risk analysis. This study uses interval type-2 fuzzy sets (IT2FSs) to represent risk preference and focuses on the associated arithmetic operation performed on the reference points and heights. Therefore, a function is proposed to integrate the reciprocal influences of the height of IT2FS for three types of risk preferences; namely, caution, impartiality, and adventurousness, with uncertainty. The proposed function is used to define arithmetic operations for the IT2FSs, including addition, subtraction, multiplication, division, multiplication by a crisp number, and exponentiation operations. Furthermore, case studies are conducted to validate and demonstrate that the proposed arithmetic operations apply to the fuzzy risk analysis and risk criteria design processes. The results of a case study reveal that a conservative expert increases the assessed risk and lowers its uncertainty. By contrast, the more radical the expert, the less important the consequence of the autonomous ship. Finally, this study discusses various functions, evaluating their computational time and performance, and recommends the most suitable options.</div></div>","PeriodicalId":19403,"journal":{"name":"Ocean Engineering","volume":"342 ","pages":"Article 122940"},"PeriodicalIF":5.5,"publicationDate":"2025-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145222327","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 universal visualization method for promoting system representation and performance prediction of underwater gliders based on deep learning","authors":"Wei Han ,&nbsp;Feng Gong ,&nbsp;Pan Wu ,&nbsp;Cheng Wang ,&nbsp;Wei Ma ,&nbsp;Peng Wang ,&nbsp;Shaoqiong Yang ,&nbsp;Wendong Niu ,&nbsp;Ming Yang","doi":"10.1016/j.oceaneng.2025.122986","DOIUrl":"10.1016/j.oceaneng.2025.122986","url":null,"abstract":"<div><div>Artificial intelligence is revolutionizing the process of product design to make it smarter and more efficient, which provides a promising technique for constant development and optimization of underwater gliders (UGs). In this case, this paper proposes a universal visualization method for system representation and performance prediction of UGs based on deep learning, which can achieve intelligent and rapid performance evaluation by learning from serialized design schemes. Dataset is built via co-simulation and image representation based on mass properties and layout forms. The architecture of the performance prediction model is optimized and its prediction proficiency is improved through dataset statistical analysis and hyperparameter analysis. The performance and interpretability of the trained model are evaluated by comparison with other methods and feature map visualization. Finally, the effectiveness and applicability of the proposed method are evaluated with a practical engineering prototype, and the results show that it can realize performance prediction with a remarkable speed while maintaining considerable efficiency. Compared with the traditional parameter-based prediction methods, the proposed method innovatively involves visualized design schemes of multiple models and multiple series, which can be applied to diversified products, broadening the application range of deep learning in intelligent design of underwater equipment.</div></div>","PeriodicalId":19403,"journal":{"name":"Ocean Engineering","volume":"342 ","pages":"Article 122986"},"PeriodicalIF":5.5,"publicationDate":"2025-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145159844","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":"Physical model tests under towing conditions of a novel floating wind-wave integrated platform","authors":"Zhenpeng Wang ,&nbsp;Xiaolong Dai ,&nbsp;Songwei Sheng ,&nbsp;Yaqun Zhang ,&nbsp;Min Chen ,&nbsp;Xinhui Chen ,&nbsp;Shanxun Yang ,&nbsp;Zhaoji Lin","doi":"10.1016/j.oceaneng.2025.122957","DOIUrl":"10.1016/j.oceaneng.2025.122957","url":null,"abstract":"<div><div>The combined development of wind and wave energy can significantly reduce economic costs and optimize marine space. The combined concept usually exhibits distinct static and dynamic stabilities during transportation phases, making dynamic research during the transportation stages critical. A novel semi-submersible wind-wave integrated platform with a “T”-shaped structure is proposed, and a physical model with and without a wind turbine installed is established to study the towing resistance, roll and pitch motion responses under towing conditions. A series of experiments are conducted in still water and regular waves, considering key factors such as towing speed, wave conditions, draft, and direction. Results indicate the platform's natural roll and pitch periods are approximately 10 s. The resistance increases with increasing of speed, and 5 knots balances stability and efficiency. At 2 m wave height, the maximum roll and pitch of platform are 0.34° and 2.59° respectively, meeting the requirements of towing specifications. Doubling the draft increases resistance by 51 %, and the roll and pitch increase and decrease accordingly, making it a potential measure to improve stability under extreme sea conditions. When towing in the 180° direction, the platform shows a trim-by-head floating state with greater resistance, which is inappropriate in towing operations.</div></div>","PeriodicalId":19403,"journal":{"name":"Ocean Engineering","volume":"342 ","pages":"Article 122957"},"PeriodicalIF":5.5,"publicationDate":"2025-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145159848","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":"Hydrofoil performance optimization based on the Kriging method","authors":"Qiaowen Yu ,&nbsp;Shigang Wang ,&nbsp;Rui Deng ,&nbsp;Dapeng Jiang ,&nbsp;Bing Zheng ,&nbsp;Suzhen Zeng","doi":"10.1016/j.oceaneng.2025.122909","DOIUrl":"10.1016/j.oceaneng.2025.122909","url":null,"abstract":"<div><div>In order to design a new type of hydrofoil, which is much more useful in improving the seakeeping performance in the condition of the same projected area, an improved Kriging surrogate model-based optimization method coupled with an MSP-EI-MSE(Minimize Surrogate Prediction-Expected Improvement-Mean Square Error) parallel infill criterion is proposed in this study. The computing time needed is reduced approximately 22.46 % and the variance is reduced nearly 45.14 % compared with the existing methods. Subsequently, it is demonstrated by the application of the method to the hydrofoils of an unmanned catamaran that, the moment induced by the optimized hydrofoils in pitch motion is increased 19.59 % per unit area. Later, model test is adopted to validate results obtained in the simulation, Particle Image Velocimetry is used to obtain the details of the flow fields around the hydrofoils and analyze the effect caused by optimization.</div></div>","PeriodicalId":19403,"journal":{"name":"Ocean Engineering","volume":"342 ","pages":"Article 122909"},"PeriodicalIF":5.5,"publicationDate":"2025-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145156852","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":"Analysis of the load characteristics of a local corner region inside a liquid tank impacting water surface obliquely","authors":"Chuntong Li ,&nbsp;Xiaomeng Luo ,&nbsp;Juyan Zheng ,&nbsp;Hang Xie ,&nbsp;Deyu Wang","doi":"10.1016/j.oceaneng.2025.122953","DOIUrl":"10.1016/j.oceaneng.2025.122953","url":null,"abstract":"<div><div>The impact load on liquid tanks is a current research focus. Unlike previous studies that concentrated on impact loads in flat regions, this paper delves into the load characteristics of triangular region based on the Volume of Fluid (VOF) method. The systematic analysis of flow field and pressure characteristics within an inclination angle range of 0–30° was conducted, revealing the effects of flow separation, air pockets and jet impact on the multi-peak fluctuation characteristics of impact loads. Through the comparison of load characteristics at different impact velocities between 5 and 20 m/s, the study identified patterns of load feature similarity. Furthermore, the research explored the effect of multi-degree-of-freedom motion on load characteristics, showing it can effectively reduce impact force by approximately 20 %. Lastly, the influence of corrugated structures on flow field velocity, pressure distribution, free surface flow, and load history was analyzed. According to the findings, corrugated structures can reduce the impact force by 50 %, effectively prevent excessive concentration in high-pressure regions, and provide new optimization insights for liquid tank design.</div></div>","PeriodicalId":19403,"journal":{"name":"Ocean Engineering","volume":"342 ","pages":"Article 122953"},"PeriodicalIF":5.5,"publicationDate":"2025-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145159749","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":"Hydrodynamic behaviors of rotatable horizontal aquaculture cage groups","authors":"Jun Zhang ,&nbsp;Yuheng Zhu ,&nbsp;Feipeng Wang ,&nbsp;Zhijian Liu ,&nbsp;Fang Wang ,&nbsp;Bin Wang ,&nbsp;Zhixin Geng","doi":"10.1016/j.oceaneng.2025.122966","DOIUrl":"10.1016/j.oceaneng.2025.122966","url":null,"abstract":"<div><div>To enhance the safety of aquaculture cages under extreme marine conditions and address the issue of netting biofouling, this study innovatively designed a horizontal aquaculture cage structure capable of floating, submerging, and rotating. A combined theoretical and experimental approach was adopted to investigate the hydrodynamic behavior of such cage groups under different layouts and marine conditions. Firstly, a dynamic model of the cage group was established based on the lumped mass method and Morison equation, and the rotatable performance of the cage and the reliability of the numerical model were verified through underwater tests on the physical model. Subsequently, taking the 1 × 4 layout cage group as the research object, the time-domain analysis method was used to analyze the effects of wave height and the ratio of cage spacing (<em>L</em>) to wavelength (<em>λ</em>) on hydrodynamic responses and mooring tension. Finally, the nonlinear dynamic response characteristics of the 1 × 4 and 2 × 2 layout cage groups under combined wave-current action were studied. The results show that the surge, heave, and pitch motions of horizontal cage groups in floating and submerged states are significantly affected by wave height and the ratio of <em>L</em><em>/</em><em>λ</em>. The submerged state can effectively suppress the pitch amplitude and reduce mooring tension. In layout design, cage spacing should be avoided to be close to the wavelength to prevent resonance and reduce the risk of extreme loads. Compared to the 1 × 4 layout, the 2 × 2 layout reduces the average standard deviation of mooring tension by 6.06 % with more uniform tension distribution. However, positive incidence of wave-current significantly increases the pitch amplitude of the rear cages in the 2 × 2 layout.</div></div>","PeriodicalId":19403,"journal":{"name":"Ocean Engineering","volume":"342 ","pages":"Article 122966"},"PeriodicalIF":5.5,"publicationDate":"2025-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145159847","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 unified framework for predicting vertical bearing capacity of fully embedded pipes/tunnels in clay seabed based on the undrained failure mechanisms","authors":"Yu Zhao ,&nbsp;Xing-Tao Lin ,&nbsp;Wei-Jian Li ,&nbsp;Jun-Chen Zhang ,&nbsp;Zhi-Yao Tian ,&nbsp;Quan-Mei Gong","doi":"10.1016/j.oceaneng.2025.122924","DOIUrl":"10.1016/j.oceaneng.2025.122924","url":null,"abstract":"<div><div>Understanding failure mechanism and predicting bearing capacity for the seabed soil-structure interaction is crucial in the design of offshore tunnel/pipeline. This study employs mesh-adaptive finite element limit analysis (FELA) to investigate the uplift/penetration failure mechanisms and bearing capacity of a tunnel/pipe segment in undrained clay seabed. Most of the critical parameters were considered in the FELA simulation, including unit weight of soil (<em>γ′</em>), undrained shear strength (<em>s</em>_u) profiles of uniform <em>s</em>_u or heterogeneous <em>s</em>_u with gradient <em>k</em>, embedment ratio (<em>H</em>/<em>D</em>), soil-structure interface tensile capacity, and interface roughness (<em>μ</em>). The criteria for the transition state between breakaway and no breakaway were quantified. When no breakaway between the structure and surrounding soil occurs, the uplift and penetration failure mode is basically the same, regardless of embedment ratio, and interface tension capacity. Dimensionless bearing capacity was quantified as functions of dimensionless parameters <em>H</em>/<em>D</em>, <em>γ′D</em>/<em>s</em>_u, <em>γ</em>′/<em>k</em>, and <em>μ</em>, for no-tension and full-tension conditions. Then, a unified predictive framework for both uplift and penetration bearing capacity of tunnel/pipe structures under arbitrary geotechnical conditions was proposed and validated. This work provides design framework for predicting uplift or penetration resistance, with particular relevance to upheaval buckling stability of offshore pipelines and anti-buoyancy stability of submerged tunnels.</div></div>","PeriodicalId":19403,"journal":{"name":"Ocean Engineering","volume":"342 ","pages":"Article 122924"},"PeriodicalIF":5.5,"publicationDate":"2025-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145156938","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":"Undisturbed wave elevation estimation: Correcting for radiation and diffraction effects in measured data near floating wind turbines","authors":"Isaac D. Sewell ,&nbsp;Amrit S. Verma ,&nbsp;Andrew J. Goupee","doi":"10.1016/j.oceaneng.2025.122863","DOIUrl":"10.1016/j.oceaneng.2025.122863","url":null,"abstract":"<div><div>A reliable estimation of the undisturbed wave elevation from full-scale measurements is required for model correlation studies for floating offshore structures, but radiation and diffraction effects from the structure itself can decrease the quality of local wave measurements when the floating structure is large compared to the wavelength of the incoming environment. To address this issue, a methodology utilizing a potential flow model is proposed to estimate the undisturbed environmental wave from local measurements in the presence of radiation and diffraction effects from a floating offshore structure. Potential flow theory is a computationally efficient approach for evaluating wave-structure interaction for radiation and diffraction. A scaled model test was performed in a wave tank to test the efficacy of this methodology in three unidirectional irregular wave environments scaled from the design load cases (DLCs) for a barge-type floating offshore wind turbine platform. The experimental campaign enabled the: (1) determination of in which environments radiated and diffracted waves significantly impacted recorded wave elevation, (2) identification of the ideal location to mount wave probes to avoid interference from the structure, and (3) evaluation of the methodology’s ability to determine accurate spectral statistics (<span><math><msub><mi>H</mi><mi>s</mi></msub></math></span>, <span><math><msub><mi>T</mi><mi>p</mi></msub></math></span>, shape factor, and total error in the spectrum) and time series wave heights. In an environment where diffraction was significant, the area of total error in the recorded spectrum was reduced by 73 % for the bow probe and by 63 % for the starboard probe. This method will be tested on a field deployed floating offshore wind turbine in the near future.</div></div>","PeriodicalId":19403,"journal":{"name":"Ocean Engineering","volume":"342 ","pages":"Article 122863"},"PeriodicalIF":5.5,"publicationDate":"2025-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145156943","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 new similarity criterion for real-time hybrid testing of floating wind turbines in wind tunnels: Verification and application","authors":"Tianxiao Luo ,&nbsp;Pan Zhang ,&nbsp;Zhixun Li ,&nbsp;Hairui Zhang ,&nbsp;Guangxing Wu ,&nbsp;Jianhua Zhang","doi":"10.1016/j.oceaneng.2025.122890","DOIUrl":"10.1016/j.oceaneng.2025.122890","url":null,"abstract":"<div><div>Accurate scaled model testing for floating wind turbines remains challenging due to limitations in traditional similarity approaches. Based on key issues such as aero-hydro mismatch, deficiencies in dynamic effect similarity, and power coefficient dissimilarity under the traditional Froude number similarity criterion, this paper proposes an improved similarity criterion specifically suited for wind tunnel model tests of floating wind turbines. The new criterion introduces three key modifications: (1) matching the tip speed ratio at the optimal power coefficient segment while compensating for power differences, enabling simultaneous power and thrust similarity; (2) deriving the crucial constraint of equal rate of change of tip speed ratio for dynamic aerodynamic similarity, subsequently determining scaling ratios for motion amplitude and frequency; and (3) matching equivalent pitch amplitude and motion frequency with rotational frequency to capture similarity for dynamic effects induced by equivalent wind shear. Validation via unsteady momentum blade element theory calculations (using the NREL 5 MW as prototype) showed significant error reductions: under sinusoidal pitch motion, power coefficient (Cp) and thrust coefficient (Ct) errors decreased by 14.87 % and 6.78 % respectively; under coupled pitch-surge motions, average Cp and Ct errors decreased by 13.68 % and 3.23 %. Wind tunnel verification using a model turbine on a 6-Degree-of-Freedom (6-DoF) motion platform further confirmed the improvement: under forced motion, power and thrust errors decreased by 24.14 % and 9.38 %; in real-time hybrid model applications, the relative error of the surge displacement response decreased by 138.5 % and the pitch displacement response by 116.6 %. This provides clear scientific guidance for the design of model experiments.</div></div>","PeriodicalId":19403,"journal":{"name":"Ocean Engineering","volume":"342 ","pages":"Article 122890"},"PeriodicalIF":5.5,"publicationDate":"2025-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145159756","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":"Effect of different pitch ratios on the flow around tandem circular cylinders with spoilers","authors":"Mücella İlkentapar ,&nbsp;Serhat Akşi̇t ,&nbsp;Ahmet Alper Öner ,&nbsp;Mustafa Serdar Genç","doi":"10.1016/j.oceaneng.2025.122933","DOIUrl":"10.1016/j.oceaneng.2025.122933","url":null,"abstract":"<div><div>This study experimentally investigates the unsteady aerodynamic characteristics of two tandem circular cylinders subjected to various pitch ratios and spoiler configurations in a controlled wind tunnel environment. The primary objective is to understand how the placement and presence of spoiler's influence flow separation, wake interference, surface pressure distributions, and overall aerodynamic performance. The experiments were conducted for three pitch ratios (2D, 4D, and 7D) and four spoiler configurations: NN (no spoilers on either cylinder), NS (spoiler on the downstream cylinder only), SN (spoiler on the upstream cylinder only), and SS (spoilers on both cylinders). Measurements included surface pressure, velocity distribution via hot-wire anemometry, and aerodynamic forces, while qualitative flow patterns were assessed using smoke-wire visualization. The results indicate that the usage of spoilers substantially alters the wake structure and pressure profiles, especially in closely spaced configurations. In the NN configuration, increasing the pitch ratio led to a progressive decoupling of the flow between the cylinders, transitioning from a merged wake to more isolated vortex shedding. In the SN and NS configurations, the asymmetrical placement of spoilers induced unsteady wake interactions and altered reattachment dynamics on the downstream body. The SS configuration exhibited the most disturbed flow regime at low pitch ratios, which gradually stabilized as the spacing increased. Violin plots derived from velocity measurements provided statistical insight into flow symmetry and turbulence intensity, while smoke visualizations captured coherent structures and transition zones across the configurations. The combined analysis demonstrates that both pitch ratio and spoiler configuration are critical parameters in controlling aerodynamic interference and unsteady wake behavior in tandem arrangements. These findings offer valuable implications for flow management and control strategies in offshore structures, cylindrical risers, and heat exchanger tube banks, where vortex-induced vibrations and flow separation play crucial roles.</div></div>","PeriodicalId":19403,"journal":{"name":"Ocean Engineering","volume":"342 ","pages":"Article 122933"},"PeriodicalIF":5.5,"publicationDate":"2025-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145222325","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}