Ocean Engineering最新文献_第6页

Study on displacement volume precise control and geometric feasibility in shifting method for hull form optimization 船型优化移位法排水量精确控制及几何可行性研究

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-02-10 DOI: 10.1016/j.oceaneng.2026.124532

Xinwang Liu, Luyao Wang, Xu Sun, Lei Yuan, Zitong Rong, Xiaohang Ji

Displacement volume is a key geometric parameter governing ship buoyancy and load capacity, significantly influencing hydrodynamic and operational performance. In hull form optimization, it is commonly imposed as a constraint to limit its variation and ensure design feasibility. However, when applying common deformation methods such as the shifting method, the mapping relationship between design variables and displacement volume change remains unclear, hindering precise volume control. Traditional hull form optimization relies on an empirical “design-verification-adjustment" iterative process, requiring repeated verification of volume constraints and gradual adjustment of the design space, resulting in low efficiency. In this study, an analytical expression for volume variation under the shifting method is derived for the first time, based on the principles of integral calculus and numerical computation. This enables the direct prediction of volume variation without the need for actual deformation, thereby avoiding the iterative trial-and-error adjustment of both new hull forms and design spaces. Additionally, a geometric feasibility criterion for the deformed hull is established using the principles of differential calculus. To validate the proposed method, a numerical study was conducted on Series 60 hull using 250 sample points. The results show excellent agreement between the volume changes computed by the derived expression and those obtained from hydrostatic principles, confirming the reliability of both the expression and the feasibility criterion. Furthermore, a resistance optimization case study was carried out for Series 60 hull at a typical speed, incorporating strict volume constraints and deformation rationality controls. A total resistance reduction of 9.55% was achieved, demonstrating the practical engineering value of the proposed methodology. This framework enables precise and direct control over displacement volume during deformation, transforming the traditional iterative empirical process into a deterministic one-step calculation, thereby significantly improving the efficiency and reliability of hull form optimization.

排水量是控制船舶浮力和承载能力的关键几何参数，对船舶的水动力性能和使用性能有重要影响。在船体形状优化中，通常采用约束来限制其变化，保证设计的可行性。然而，在应用位移法等常用变形方法时，设计变量与位移体积变化之间的映射关系不明确，不利于精确控制体积。传统的船体形状优化依赖于经验性的“设计-验证-调整”迭代过程，需要反复验证体积约束，逐步调整设计空间，效率较低。本文基于积分学和数值计算的原理，首次导出了位移法下体积变化的解析表达式。这使得无需实际变形即可直接预测体积变化，从而避免了对新船体形状和设计空间的反复试验和错误调整。此外，利用微分学原理建立了变形船体的几何可行性判据。为了验证该方法的有效性，对60系列船体进行了250个采样点的数值研究。计算结果表明，计算所得的体积变化与流体静力学原理计算结果吻合良好，证实了该表达式和可行性准则的可靠性。此外，对典型航速下的60系列船体进行了阻力优化案例研究，纳入了严格的体积约束和变形合理性控制。总电阻降低了9.55%，证明了该方法的实际工程价值。该框架能够精确、直接地控制变形过程中的位移量，将传统的迭代经验过程转变为确定性的一步计算，从而显著提高船体形状优化的效率和可靠性。

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引用次数: 0

ShipSeer: Pushing accuracy-performance boundaries in ship motion prediction with spectral and multi-component analysis ShipSeer：用光谱和多成分分析推动船舶运动预测的准确性和性能界限

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-02-10 DOI: 10.1016/j.oceaneng.2026.124611

Chunyang Yu , Yuntao Mao , Dengke Liu, Ziwei Chen

Accurate ship motion prediction is vital for ensuring maritime safety, cargo stability, and operational efficiency. However, nonlinear ship dynamics, long-term dependency challenges, multi-step error accumulation, and limited onboard computational resources make long-term prediction difficult. This paper introduces ShipSeer, a resource-efficient MLP-based multi-input multi-output forecasting framework that jointly predicts eight ship motion states over long horizons. By combining spectral and multi-component analysis, ShipSeer can address the above problems while efficiently extracting key frequencies and parallelly modeling different temporal patterns. Evaluated on four real-world datasets, ShipSeer outperforms nine state-of-the-art models, achieving 19.67% higher accuracy and 49.25% faster inference. Robustness and ablation studies confirm the effectiveness of each module, demonstrating ShipSeer's practical value in advancing the intelligence of modern marine systems under complex and noisy sea conditions. Furthermore, experiments demonstrate how environmental conditions are reflected in the spectral characteristics of ship motion data, providing physically consistent explanations for the observed prediction behavior.

准确的船舶运动预测对于确保海上安全、货物稳定和运营效率至关重要。然而，非线性船舶动力学、长期依赖挑战、多步误差积累以及有限的船载计算资源使得长期预测变得困难。本文介绍了一种基于多输入多输出的资源高效预测框架ShipSeer，该框架可以在长时间内联合预测八种船舶运动状态。通过结合频谱和多分量分析，ShipSeer可以解决上述问题，同时有效地提取关键频率并并行建模不同的时间模式。在四个真实数据集上进行评估后，ShipSeer优于9个最先进的模型，准确率提高了19.67%，推理速度提高了49.25%。鲁棒性和烧蚀研究证实了每个模块的有效性，展示了ShipSeer在复杂和嘈杂海况下推进现代海洋系统智能方面的实用价值。此外，实验证明了环境条件如何反映在船舶运动数据的光谱特征中，为观测到的预测行为提供了物理上一致的解释。

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引用次数: 0

Statistical evaluation of joint occurrence among wind, wave, and seismic loads for offshore wind turbine design 海上风力机设计中风、浪、震载荷联合作用的统计评估

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-02-10 DOI: 10.1016/j.oceaneng.2026.124458

Hiroaki Kashima , Hidenori Takahashi

A key challenge in offshore wind turbine design is evaluating the joint occurrence of wind, waves, and earthquakes. However, the consistency between prescribed load combinations in current design standards and actual joint occurrence frequencies has not been sufficiently validated. Current standards simplify wind-wave dependence and combine seismic actions exclusively with weak wind and calm seas, which may be overly conservative or overlook rare but critical scenarios. This study constructed a dataset by extracting earthquake events from long-term simultaneous observations surrounding Japan and combining them with concurrent wind-wave conditions. The statistical dependence and joint occurrence characteristics of the three loads were evaluated. Statistical analysis showed that seismic motions had weak correlation with meteorological-oceanographic conditions. Consequently, the earthquake load case assuming weak wind and calm seas prescribed in current standards is reasonable in some respects, as it corresponds to frequently observed conditions. However, during wind-wave-dominant periods, “moderate wind and wave” conditions occur frequently, suggesting the weak-wind assumption may not always hold. In swell-dominant periods, cases of “high swell under weak wind coinciding with seismic motion” were observed, posing resonance risks for floating turbines. These findings provide statistical support for refining and supplementing design load cases toward more rational multi-hazard offshore wind turbine design.

海上风力涡轮机设计的一个关键挑战是评估风、浪和地震的共同发生。然而，现行设计标准中规定的荷载组合与实际接头发生频率之间的一致性尚未得到充分验证。目前的标准简化了对风浪的依赖，只将地震活动与弱风和平静的海面结合起来，可能过于保守或忽视了罕见但关键的情况。本研究通过提取日本周边长期同步观测的地震事件，并将其与同期风浪条件相结合，构建了一个数据集。对三种荷载的统计相关性和共同赋存特征进行了评价。统计分析表明，地震运动与气象-海洋条件的相关性较弱。因此，现行标准规定的假定弱风和静海的地震荷载情况在某些方面是合理的，因为它与经常观测到的情况相对应。然而，在风浪占主导地位的时期，“中等风浪”的情况经常发生，这表明弱风的假设可能并不总是成立。在膨胀主导时期，观察到“弱风下的高膨胀与地震运动相吻合”的情况，对浮式涡轮机构成共振风险。这些研究结果为完善和补充设计载荷工况以实现更合理的多灾害海上风力发电机设计提供了统计支持。

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引用次数: 0

Accurate tidal level forecasting over an extended horizon using a deep learning method 使用深度学习方法在扩展的范围内进行准确的潮位预测

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-02-10 DOI: 10.1016/j.oceaneng.2026.124630

Xiaoxue Wang , Zaiyang Zhou , Tao Qin , Yonghui Zhu , Hualong Luan , Yujin Dong , Jianzhong Ge

Tidal level forecasting is crucial for guaranteeing estuarine and coastal economic activities and mitigating coastal hazards. Accurate and efficient predictions of tidal levels facilitate timely responses to catastrophic events related to water surface disturbances, such as storm surges generated by tropical cyclones. This study proposes an innovative hybrid model that integrates convolutional neural networks (CNN) with a self-attention mechanism to capture both periodic and aperiodic signals in tidal fluctuations, enabling accurate 5-day forecasts. The model incorporates a temporal attention layer to dynamically weight tidal features across varying temporal scales, thereby optimizing their relative contributions. Consequently, this CNN-Attention architecture improves prediction accuracy over extended forecast horizons, maintaining robust performance even for predictions up to 120 h. The methodology is implemented and validated using data from 13 tide gauge stations in the Changjiang Estuary, achieving station-averaged root mean square errors (RMSE) of 12.1 cm, mean absolute errors (MAE) of 9.9 cm, correlation coefficients (CORR) of 0.994, and R-squared values (

R^{2}

) of 0.98 across all stations. This approach is adaptable and can be applied to diverse tidal regimes in various regions.

潮位预报是保证河口和沿海经济活动、减轻沿海灾害的重要手段。准确和有效的潮位预测有助于及时应对与水面扰动有关的灾难性事件，例如热带气旋产生的风暴潮。本研究提出了一种创新的混合模型，该模型将卷积神经网络（CNN）与自关注机制相结合，可以捕获潮汐波动中的周期性和非周期性信号，从而实现5天的准确预测。该模型结合了一个时间关注层，在不同的时间尺度上动态加权潮汐特征，从而优化它们的相对贡献。因此，这种CNN-Attention架构提高了预测精度，即使在120小时内也能保持稳定的预测性能。该方法使用长江口13个潮汐测量站的数据进行了实施和验证，所有站点的平均均方根误差（RMSE）为12.1 cm，平均绝对误差（MAE）为9.9 cm，相关系数（CORR）为0.994，r平方值（R2）为0.98。这种方法适应性强，可适用于不同地区的不同潮汐情况。

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引用次数: 0

Optimization design of a pre-swirl duct for a container ship: A simulation-based design method integrating a support vector regression surrogate model 集装箱船预旋风道优化设计：基于支持向量回归代理模型的仿真设计方法

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-02-10 DOI: 10.1016/j.oceaneng.2026.124574

Zhongzhong Zheng , Qingyang Xu , Yukun Feng , Yi Dai , Zuogang Chen , Yanfeng Wu

This study proposes a multitechnology-integrated pre-swirl duct (PSD) design method that integrates the design of experiments (DOE), high-fidelity numerical simulations, support vector regression (SVR), and multi-island genetic algorithm (MIGA), facilitating efficient PSD design with profound energy saving performance. To validate the proposed methodology, we demonstrated an optimized design of a PSD for an 8800 TEU container ship. Reynolds-averaged Navier-Stokes equations (RANSE) were employed to predict ship propulsion performance, and the prediction accuracy was verified by comparing model test results with numerical simulation results. 24 critical PSD parameters were extracted based on wake characteristics and the structural features of PSDs. Parametric modeling was implemented using a computer-aided design (CAD) approach. The design space was sampled with 280 uniformly distributed sample points, generated via optimal Latin hypercube design (OptLHD) method. Self-propulsion performance simulations were completed via high-fidelity numerical simulations featuring fully resolved propellers. An SVR-based surrogate model was constructed to replace numerical simulations and enhance optimization efficiency. With the minimization of delivered power to the propeller as the objective function, the MIGA was used to identify optimal PSD parameters, and the energy saving performance of the optimized PSD was validated through model testing. The designed PSD reduces the power consumption of the container ship in full-scale (2.45% reduction at the design speed). It maintains favorable energy saving performance in the Froude number (Fr) range of 0.116−0.183. Wake field analysis indicates that the PSD effectively generates pre-swirl flow, thereby improving propulsion efficiency. Vortical structure analysis further reveals that the PSD fragments the bilge vortex, reduces vortex strength and energy losses in the wake. The Energy Efficiency Existing Ship Index (EEXI) assessment confirms that PSD installation reduces the EEXI value of the target ship, proving its effectiveness as an energy saving retrofit measure.

本研究提出了一种集实验设计（DOE）、高保真数值模拟、支持向量回归（SVR）和多岛遗传算法（MIGA）于一体的多技术集成预旋流风管（PSD）设计方法，可实现高效的预旋流风管设计，并具有较好的节能效果。为了验证提出的方法，我们展示了8800 TEU集装箱船的PSD优化设计。采用雷诺平均Navier-Stokes方程（RANSE）对船舶推进性能进行预测，并通过模型试验结果与数值模拟结果的对比验证了预测的准确性。基于尾迹特征和PSD的结构特征，提取了24个PSD关键参数。参数化建模采用计算机辅助设计（CAD）方法实现。通过最优拉丁超立方体设计（OptLHD）方法生成280个均匀分布的采样点，对设计空间进行采样。采用全分辨螺旋桨进行高保真数值模拟，完成了自推进性能模拟。为了取代数值模拟，提高优化效率，建立了基于svr的代理模型。以向螺旋桨输出功率最小为目标函数，采用MIGA方法辨识最佳PSD参数，并通过模型试验验证了优化后的PSD节能性能。设计的PSD降低了集装箱船的全尺寸功率消耗（在设计航速下降低2.45%）。在弗鲁德数（Fr） 0.116 ~ 0.183范围内保持良好的节能性能。尾流场分析表明，PSD能有效地产生预旋流，从而提高推进效率。旋涡结构分析进一步揭示了PSD破碎舱底涡，降低了旋涡强度和尾迹中的能量损失。现有船舶能源效率指数（EEXI）评估证实，PSD安装降低了目标船舶的EEXI值，证明了其作为节能改造措施的有效性。

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引用次数: 0

Numerical investigation of the influence of vertical loading on the lateral response of disconnected piled raft foundation 竖向荷载对不连通桩筏基础横向响应影响的数值研究

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-02-10 DOI: 10.1016/j.oceaneng.2026.124498

Ankit Kumar Suman, J.S. Rajeswari

A Disconnected Piled Raft Foundation (DPRF) enhances load distribution and reduces settlement by introducing a granular cushion between the raft and piles. While previous studies mainly focused on simplified or purely vertical loading, this study presents a three-dimensional numerical investigation of DPRFs in sand to investigate the effect of vertical loading on their lateral response. Numerical analysis is performed using a finite difference program (FLAC3D), where the soil and cushion are modelled using an elastic-perfectly plastic Mohr-Coulomb constitutive model, and the raft and piles are represented by linear elastic elements with appropriate interface formulations. A comprehensive parametric study is performed to examine the influence of various parameters on settlement, raft rotation, pile load sharing, and lateral resistance under vertical-horizontal (V-H) loading. Results indicate that the lateral capacity of DPRF increases with vertical load up to approximately 0.5 times the vertical capacity, beyond which it stabilises. Pile load sharing is relatively insensitive to vertical load but decreases from approximately 35-38% to 18-20% with increasing cushion thickness. The edge piles experience higher shear forces and bending moments, while central piles primarily carry axial loads. Additionally, new predictive equations for DPRF capacity under vertical and V-H loading are proposed, demonstrating high accuracy.

断开桩筏基础（DPRF）通过在筏和桩之间引入颗粒垫层来增强荷载分布并减少沉降。以往的研究主要集中在简化或纯垂直加载上，而本研究对砂土中的dprf进行了三维数值研究，以研究垂直加载对其横向响应的影响。采用有限差分程序（FLAC3D）进行数值分析，其中土壤和垫层采用弹塑性莫尔库仑本构模型，筏板和桩采用具有适当界面公式的线弹性单元表示。进行了全面的参数研究，以检查在垂直水平（V-H）荷载下各种参数对沉降、筏板旋转、桩荷载分担和侧阻力的影响。结果表明，随着竖向荷载的增加，DPRF的横向承载力增大，达到竖向承载力的约0.5倍，超过竖向荷载后，DPRF趋于稳定。桩分担荷载对竖向荷载相对不敏感，但随着垫层厚度的增加，桩分担荷载从大约35-38%下降到18-20%。边缘桩承受较大的剪力和弯矩，中心桩主要承担轴向荷载。此外，还提出了新的垂直载荷和V-H载荷下DPRF容量的预测方程，具有较高的精度。

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引用次数: 0

Numerical investigation on vibration mechanisms of harbour seal whiskers in fin wakes during acceleration and cruising 加速和巡航时海豹须尾迹振动机理的数值研究

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-02-10 DOI: 10.1016/j.oceaneng.2026.124600

Hanghao Zhao , Zhimeng Zhang , Chunning Ji , Xianghe Li , Muyuan Du , Dekui Yuan , Md Mahbub Alam

Endowed with extraordinary sensitivity, Harbour seal whiskers can detect and track hydrodynamic wakes from moving bodies. To exploit this biological capability, this study employs the immersed boundary method to numerically investigate the flow-induced vibrations of an elastically mounted whisker model subjected to caudal fin wakes under acceleration (St = 0.65) and cruising (St = 0.3, 0.22) conditions. The analysis encompasses the whisker's vibration responses, wake structures, lift coefficients, and the interaction mechanisms between the whisker and fin wakes. In the accelerating mode, the caudal fin generates three-dimensional hairpin vortices that gradually contract along the span during downstream propagation. These vortices exert localized influence on the whisker's midspan region, predominantly inducing vortex-induced vibrations (VIV). Conversely, in the cruising mode, the caudal fin produces rectangular vortex rings propagating parallel to the flow, which exert extensive effects on the downstream whisker across a broader span. This leads to wake-induced vibrations (WIV) dominating the whisker's dynamic responses, with the dominant frequency synchronized to the caudal fin's pitching and heaving frequencies. Driven by the combined effects of vortex ring spacing and vorticity, the whisker-fin wake interaction modulates the whisker's lift coefficients and energy transfer distributions. These findings deepen the understanding of Harbour seal whiskers' hydrodynamic sensing mechanisms and provide critical theoretical guidance for the development of biomimetic fish-detecting underwater sensors.

海海豹须具有非凡的灵敏度，能探测和追踪运动物体的水动力尾迹。为了利用这一生物学特性，本研究采用浸入边界法对尾鳍尾迹在加速（St = 0.65）和巡航（St = 0.3, 0.22）条件下弹性安装的须模型的流致振动进行了数值研究。分析包括须的振动响应、尾迹结构、升力系数以及须与鳍尾迹之间的相互作用机制。在加速模式下，尾鳍在下游传播过程中产生三维发夹涡，沿跨段逐渐收缩。这些涡对晶须的跨中区域施加局部影响，主要引起涡激振动（VIV）。相反，在巡航模式下，尾鳍产生与水流平行传播的矩形涡环，在更大的跨度上对下游须产生广泛的影响。这导致尾迹诱发振动（WIV）主导了须的动态响应，主导频率与尾鳍的俯仰和起伏频率同步。在涡环间距和涡量的共同作用下，须-鳍尾迹相互作用调节着须的升力系数和能量传递分布。这些发现加深了对海豹须水动力传感机制的理解，为开发仿生水下探测鱼类传感器提供了重要的理论指导。

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引用次数: 0

Impact of sea level rise on storm surge dynamics during cold surges in the northern East China Sea: Relevance of surge variability to semidiurnal tidal regime 海平面上升对东海北部寒潮期间风暴潮动态的影响：风暴潮变率与半日潮势的相关性

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-02-10 DOI: 10.1016/j.oceaneng.2026.124590

Xuecheng Zhang , Luming Shi , Bingchen Liang , Guoxiang Wu , Zhenlu Wang

This study investigates the influence of sea level rise (SLR) on storm surge dynamics during cold surge events in the northern East China Sea. Numerical simulations were conducted for two historical events, one characterized by positive surge and the other by negative surges, under multiple SLR scenarios. The analysis focuses on SLR-induced modifications in surge magnitude, timing, spectral structure, and tidal interactions. Results reveal that SLR alters storm surge behavior beyond baseline elevation, inducing spatially heterogeneous and nonlinear responses. Surge amplitudes generally decreased with rising sea levels, especially for positive surges while negative surges exhibited smaller but more temporally persistent and high-frequency fluctuations. Wavelet analysis revealed that high-frequency surge components particularly in the semidiurnal band, played a dominant role in modulating surge variability. Wavelet coherence further linked these changes to variations in semidiurnal tidal constituents. Moreover, maximum storm tide increased across much of the study domain, reaching up to 25% above the imposed SLR, while the relative contributions of surge and tide to total water level declined. These findings underscore the importance of incorporating cold surge dynamics and nonlinear tidal interactions into coastal hazard assessments, particularly in mid-latitude marginal seas where wintertime events may rival tropical cyclones in coastal impact.

本文研究了东海北部寒潮期间海平面上升对风暴潮动力学的影响。在多个单反场景下，分别对正浪涌和负浪涌两个历史事件进行了数值模拟。分析的重点是slr引起的浪涌幅度、时间、光谱结构和潮汐相互作用的变化。结果表明，SLR改变了风暴潮行为，导致了空间异质性和非线性响应。浪涌幅度一般随海平面上升而下降，特别是正浪涌，而负浪涌的波动较小，但在时间上更持久，频率更高。小波分析表明，高频浪涌分量在调制浪涌变率中起主导作用，尤其是在半日波段。小波相干性进一步将这些变化与半日潮成分的变化联系起来。此外，最大风暴潮在大部分研究区域都有所增加，最高可达强加SLR以上的25%，而浪涌和潮汐对总水位的相对贡献则有所下降。这些发现强调了将寒潮动力学和非线性潮汐相互作用纳入沿海灾害评估的重要性，特别是在冬季事件可能与热带气旋的沿海影响相媲美的中纬度边缘海域。

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引用次数: 0

Digital twin system for deepwater well construction: Enhancing operational efficiency and safety 深水井建设数字孪生系统：提高作业效率和安全性

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-02-09 DOI: 10.1016/j.oceaneng.2026.124378

Dongsheng Xu , Jin Yang , Haiyan Zheng , Bin Chen , De Yan , Jianchun Fan , Qingying Tang , Yingfang Zhou

Deepwater oil and gas resources are vital to global energy supply, yet their development often faces challenges such as prolonged construction cycles, low efficiency, high emissions, and operational failures. To tackle these challenges, this study analyzes how operational and geotechnical factors affect conductor installation time and bearing capacity, during jetting and waiting stages. The intelligent optimization algorithm integrating MT-FCNN, LSTM, and PSO was proposed. A digital twin system for deepwater well construction is established for the first time, employing a modularly coupled architecture to integrate installation and post-installation processes. Validation results show that the DWC system exhibits strong performance in predicting jetting flow rates and controlling ROP during conductor installation. The model achieved a coefficient of determination R² above 0.95 and MAPE below 6 %. In beach-scale experiments, all measured values of time-varying bearing capacity fell within the 95 % confidence interval of the DWC system predictions, demonstrating its high accuracy. Finally, the case study was conducted to analyze the impact of flow rate and waiting time on construction parameters and operational decisions. The findings provide a solid theoretical and technical foundation for intelligent decision-making and enhanced reliability in deepwater well construction.

深水油气资源对全球能源供应至关重要，但其开发往往面临施工周期长、效率低、排放高、操作失败等挑战。为了应对这些挑战，本研究分析了在喷射和等待阶段，操作和岩土因素如何影响导体安装时间和承载能力。提出了将MT-FCNN、LSTM和粒子群算法相结合的智能优化算法。首次建立了用于深水井施工的数字孪生系统，采用模块化耦合架构集成安装和安装后流程。验证结果表明，DWC系统在预测喷流速率和控制钻速方面表现出色。模型的决定系数R2大于0.95，MAPE小于6%。在海滩尺度实验中，实测的时变承载力值均落在DWC系统预测值的95%置信区间内，具有较高的准确性。最后，通过实例分析了流量和等待时间对施工参数和运营决策的影响。研究结果为深水井建设的智能化决策和可靠性提高提供了坚实的理论和技术基础。

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引用次数: 0

Parametric analysis and optimization of lift-type vertical axis wind turbines using machine learning techniques 基于机器学习技术的升力式垂直轴风力涡轮机参数分析与优化

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-02-09 DOI: 10.1016/j.oceaneng.2026.124569

H.Y. Peng , H.H. Huang , H.J. Liu , Q.B. Lin

The power coefficients (C_p) of helical and Φ-type vertical axis wind turbines remain insufficiently explored compared with the H-type ones. A unified machine learning (ML) model was developed to conduct the parametric study of C_p across the H-type, helical, and Φ-type turbines with various structural parameters and turbulence intensity (I_u). Three-dimensional computational fluid dynamics (CFD) simulations, validated against experimental data, were conducted to generate a reliable dataset and elucidate the flow mechanisms. C_p of the Φ-type turbine is insensitive to the aspect ratio (AR) due to minimal tip loss, whereas a larger AR of the helical turbine expands midspan regions unaffected by tip vortices, improving the maximum torque coefficient (C_m) and C_p. Higher solidity (σ) reduces the optimal tip speed ratio and induces larger angles of attack, slightly aggravating the dynamic stall of helical turbines and decreasing C_m. Positive pitch angles (β), orienting leading edges inward, decrease the negative C_m and increase C_p. For helical turbines, increased twist angles reduce C_p, and the effects of parameters on C_p are mutually independent. The curvature ratio of the Φ-type turbine and I_u only slightly affect C_p. The particle swarm optimization algorithm incorporated with the ML model effectively improves C_p for all turbines.

与h型风力机相比，螺旋和Φ-type垂直轴风力机的功率系数（Cp）研究还不够。建立了统一的机器学习（ML）模型，对不同结构参数和湍流强度（Iu）下h型、螺旋型和Φ-type涡轮的Cp进行参数化研究。三维计算流体动力学（CFD）模拟与实验数据进行了验证，生成了可靠的数据集，并阐明了流动机理。由于叶尖损失较小，Φ-type涡轮的Cp对展弦比（AR）不敏感，而较大的AR扩大了不受叶尖涡影响的跨中区域，提高了最大扭矩系数（Cm）和Cp。较高的固体度（σ）降低了最佳叶尖速比，导致较大的攻角，略微加剧了涡轮的动态失速，减小了Cm。正俯仰角（β）使前缘向内，减小负Cm，增大Cp。对于螺旋涡轮，增大扭转角减小Cp，各参数对Cp的影响是相互独立的。Φ-type涡轮曲率比和Iu对Cp影响较小，结合ML模型的粒子群优化算法有效提高了所有涡轮的Cp。

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引用次数: 0