International Journal of Naval Architecture and Ocean Engineering最新文献

Numerical investigation of control strategies on a coupled ship propulsion system in waves 波浪中耦合船舶推进系统控制策略的数值研究

IF 3.9 3区工程技术 Q2 ENGINEERING, MARINE

International Journal of Naval Architecture and Ocean Engineering

Pub Date : 2026-01-01 Epub Date: 2026-01-28 DOI: 10.1016/j.ijnaoe.2026.100745

Chuma Ncobo, Jonas Thiaucourt, Xavier Tauzia, Lionel Gentaz

This paper investigates two engine control strategies — constant rack (CR) and speed controller (SC) — for a coupled ship propulsion system in regular head waves. The study decomposes the efficiency chain into components to identify physical mechanisms behind performance differences. By integrating a mean value engine model with a time-domain ship simulator, we analyze transient interactions between hull, propeller, and engine under realistic seaway conditions. Results demonstrate that CR achieves superior fuel efficiency (up to 2.49% improvement), particularly in long-wavelength seas. This advantage stems from reduced turbo-lag effects and more stable air–fuel dynamics that minimize transient thermodynamic losses. However, CR induces significant engine speed fluctuations that may limit practical application. In contrast, SC provides better speed regulation but increases fuel consumption due to turbo-lag and unsteady air–fuel dynamics. Hydrodynamic effects contribute through control-strategy-induced variations in ship speed and wave resistance, though to a lesser extent. These findings highlight the importance of modeling both engine dynamics and nonlinear hydrodynamic effects when evaluating propulsion control strategies.

本文研究了船舶耦合推进系统在规则头波条件下的两种发动机控制策略——恒齿条控制（CR）和航速控制（SC）。该研究将效率链分解为组件，以确定性能差异背后的物理机制。通过将发动机均值模型与时域船舶模拟器相结合，分析了实际航道条件下船体、螺旋桨和发动机之间的瞬态相互作用。结果表明，CR系统的燃油效率达到了卓越的水平（提高了2.49%），特别是在长波长海域。这一优势源于减少了涡轮滞后效应和更稳定的空气-燃料动力学，最大限度地减少了瞬态热力学损失。然而，CR引起显著的发动机转速波动，可能限制实际应用。相比之下，SC提供了更好的速度调节，但由于涡轮滞后和不稳定的空气-燃料动力学增加了油耗。水动力效应通过控制策略引起的船速和波浪阻力的变化而起作用，尽管程度较小。这些发现强调了在评估推进控制策略时建立发动机动力学和非线性水动力效应模型的重要性。

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引用次数: 0

Study on the horizontal ultimate bearing capacity of offshore wind turbine monopile foundations in sand 海上风电场单桩基础水平极限承载力研究

IF 3.9 3区工程技术 Q2 ENGINEERING, MARINE

International Journal of Naval Architecture and Ocean Engineering

Pub Date : 2026-01-01 Epub Date: 2026-01-20 DOI: 10.1016/j.ijnaoe.2026.100748

Hongwang Ma , Tong Wu

The horizontal ultimate bearing capacity (HUBC) is a crucial design parameter of monopile foundations, significantly impacting their safety and economic efficiency. It is typically determined by theoretical or empirical approaches in which the monopile is assumed to be rigid. However, actual monopiles are generally semi-rigid. This paper presents a study on the HUBC of both rigid and semi-rigid piles by means of theoretical analysis and numerical simulations. A correction factor is derived, and a general formula is established for the calculation of the correction factor. Validation is performed using the OC3 5 MW monopile as a case study. Upon incorporating the effect of elastic deformation, the HUBC decreases from 63,290 kN to 42,683 kN, achieving a reduction rate of 32.6 %. The research findings demonstrate that for large-diameter piles, the rigid pile assumption is no longer valid, and the reduction effect arising from the elastic deformation of the pile shaft must be taken into consideration. The method proposed in this study can be directly applied to preliminary engineering design or code verification, thereby realizing the rapid and accurate estimation of the HUBC of wind turbine monopile in sand.

水平极限承载力是单桩基础的重要设计参数，对单桩基础的安全性和经济性有着重要的影响。它通常由理论或经验方法确定，其中假定单桩是刚性的。然而，实际的单桩通常是半刚性的。本文采用理论分析和数值模拟相结合的方法，对刚性桩和半刚性桩的地基承载力进行了研究。导出了修正系数，并建立了修正系数计算的通用公式。以OC3 5 MW单堆为例进行验证。考虑弹性变形的影响后，HUBC从63290 kN降低到42683 kN，降低率为32.6%。研究结果表明，对于大直径桩，刚性桩假设不再成立，必须考虑桩身弹性变形产生的减振效应。本文提出的方法可直接应用于工程初步设计或规范验证，从而实现砂土中风电机组单桩HUBC的快速准确估算。

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引用次数: 0

Long-term ship trajectory prediction using a transformer with inverted attention and feature augmentation 利用反向注意力和特征增强的变压器进行长期船舶轨迹预测

IF 3.9 3区工程技术 Q2 ENGINEERING, MARINE

International Journal of Naval Architecture and Ocean Engineering

Pub Date : 2026-01-01 Epub Date: 2026-01-16 DOI: 10.1016/j.ijnaoe.2026.100744

Sangseok Lee, Han Jin Lee, Wonhee Lee

Maritime transportation is essential for global trade, with the increasing ship traffic necessitating accurate trajectory prediction for enhanced safety and efficiency. In this study, a transformer-based architecture is proposed for long-term ship trajectory prediction. Feature augmentation is performed by deriving kinematic and directional variables from raw AIS data, and trajectory clustering is applied using dynamic time warping. An inverted attention mechanism is employed, to compute the attention across variables rather than temporal positions, thereby enhancing scalability in high-dimensional settings and enabling explicit modeling of variable dependencies. The encoded representations are mapped to the prediction horizon through a multilayer perceptron decoder. Comprehensive experiments on AIS trajectory datasets demonstrated that the proposed framework attains higher accuracy in both short- and long-term prediction tasks. The results indicate that the integration of feature augmentation and inverted attention enhances predictive accuracy, robustness, and generalization for maritime trajectory prediction.

海上运输对全球贸易至关重要，随着船舶交通量的增加，需要准确的轨迹预测以提高安全性和效率。本文提出了一种基于变压器的船舶长期轨迹预测体系结构。通过从原始AIS数据中提取运动学和方向变量来进行特征增强，并使用动态时间规整应用轨迹聚类。采用了一种反向注意力机制来计算跨变量而不是时间位置的注意力，从而增强了高维设置中的可扩展性，并实现了变量依赖关系的显式建模。编码后的表示通过多层感知器解码器映射到预测视界。在AIS轨迹数据集上的综合实验表明，该框架在短期和长期预测任务中都具有较高的精度。结果表明，特征增强和反向注意的结合提高了海上弹道预测的预测精度、鲁棒性和泛化能力。

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引用次数: 0

Development of a novel model testing methodology for integrated performance evaluation of a wave energy converters of floating type 浮式波浪能转换器综合性能评估的新型模型测试方法的发展

IF 3.9 3区工程技术 Q2 ENGINEERING, MARINE

International Journal of Naval Architecture and Ocean Engineering

Pub Date : 2026-01-01 DOI: 10.1016/j.ijnaoe.2025.100737

Yoon-Jin Ha, Jeong-Seok Kim, Kilwon Kim, Kyong-Hwan Kim, Ji-Yong Park

In this study, a new model-testing methodology, termed the Real-Time Hybrid Model Test, was developed to evaluate the integrated performance of floating-type wave energy converters (FWECs) in a wave basin. The proposed technique incorporates a full-scale hydraulic power take-off (PTO) system, generator, and power conversion system (PCS), as well as a Maximum Power Point Tracking (MPPT) control algorithm to maximize electrical power extraction. In the Real-Time Hybrid Model Test, the measured motion of the FWEC model at each sampling interval is converted to full scale and supplied as input to a real-time full-scale simulation. Based on this input, the full-scale hydraulic PTO, generator, and PCS responses—including the MPPT control actions—are numerically computed. The resulting full-scale PTO load is then dynamically scaled down and applied to the physical model using a linear-motor actuator, thereby establishing a closed-loop interaction between the physical model and the numerical PTO system. The motion Response Amplitude Operators (RAOs) and the optimal hydraulic PTO force were evaluated in regular waves, and the performance of the proposed technique was further assessed in white-noise waves by comparing the results with those obtained from a conventional model test. The experimental results demonstrate that the Real-Time Hybrid Model Test provides a reliable and effective framework for evaluating FWECs, offering significant advantages in reproducing realistic PTO dynamics during physical model experiments.

在本研究中，开发了一种新的模型测试方法，称为实时混合模型测试，以评估波浪盆地中浮动型波浪能转换器（FWECs）的综合性能。所提出的技术包括全尺寸液压动力输出（PTO）系统、发电机和功率转换系统（PCS），以及最大功率点跟踪（MPPT）控制算法，以最大限度地提取电力。在实时混合模型测试中，FWEC模型在每个采样间隔的测量运动被转换为满量程，并作为实时全量程仿真的输入。基于此输入，全尺寸液压PTO，发电机和PCS响应-包括MPPT控制动作-进行数值计算。然后，将得到的全尺寸PTO负载动态缩小，并使用线性电机执行器将其应用于物理模型，从而在物理模型和数值PTO系统之间建立闭环相互作用。在规则波中对运动响应幅值算子（RAOs）和最优液压PTO力进行了评估，并通过与常规模型试验结果的比较，进一步评估了该技术在白噪声波中的性能。实验结果表明，实时混合模型测试为FWECs评估提供了一个可靠、有效的框架，在物理模型实验中再现真实的PTO动力学具有显著的优势。

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引用次数: 0

Assessing the performance of PANS and RANS for accurate wake flow prediction around the KVLCC2 评估pan和RANS在KVLCC2周围尾流准确预测中的性能

IF 3.9 3区工程技术 Q2 ENGINEERING, MARINE

International Journal of Naval Architecture and Ocean Engineering

Pub Date : 2026-01-01 Epub Date: 2026-01-14 DOI: 10.1016/j.ijnaoe.2026.100741

Hyeri Lee , Changhun Lee , Woochan Seok

This study presents a comparative analysis of the partially-averaged Navier-Stokes (PANS) and Reynolds-averaged Navier-Stokes (RANS) models for predicting secondary turbulence flows in the propeller plane of the KRISO Very Large Crude Carrier 2 (KVLCC2). Numerical simulations were performed using the open-source Computational Fluid Dynamics (CFD) software OpenFOAM, and the results were validated against experimental data. The study specifically examines the capability of both models to capture unsteady flow phenomena, particularly in regions of anisotropic turbulence, such as the hook-shaped vortices observed in the wake of the KVLCC2. The performance of the models was also evaluated at different grid resolutions, with the PANS model demonstrating superior ability to resolve intricate vortex structures, including the hook-shaped vortex in the propeller plane. Notably, the PANS model exhibited enhanced accuracy with finer grids, leading to improved resolution of turbulent kinetic energy distributions. These findings highlight the advantages of PANS over RANS in accurately predicting wake characteristics and provide valuable insights for improving CFD-based propeller design.

本文对部分平均Navier-Stokes （PANS）和reynolds -average Navier-Stokes （RANS）模型进行了对比分析，用于预测KRISO超大型原油运输船2号（KVLCC2）螺旋桨飞机的二次湍流。利用开源计算流体力学（CFD）软件OpenFOAM进行了数值模拟，并与实验数据进行了验证。该研究特别检验了两种模型捕捉非定常流动现象的能力，特别是在各向异性湍流区域，例如在KVLCC2尾迹中观察到的钩形涡。在不同网格分辨率下对模型的性能进行了评估，结果表明，PANS模型对复杂的涡旋结构（包括螺旋桨平面上的钩形涡旋）具有较好的求解能力。值得注意的是，网格越细，PANS模型的精度越高，从而提高了湍流动能分布的分辨率。这些发现突出了PANS在准确预测尾流特性方面优于RANS的优势，并为改进基于cfd的螺旋桨设计提供了有价值的见解。

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引用次数: 0

Numerical investigation on the turning motion of a near-surface self-propelled submarine 近水面自航潜艇转向运动的数值研究

IF 3.9 3区工程技术 Q2 ENGINEERING, MARINE

International Journal of Naval Architecture and Ocean Engineering

Pub Date : 2026-01-01 Epub Date: 2025-12-08 DOI: 10.1016/j.ijnaoe.2025.100718

Haipeng Guo , Yi Liu , Junyu Ge , Lin Du , Guangnian Li

The present work performs a numerical study on the turning motion of a near surface self-propelled submarine. The turbulent flow around the submarine is solved by using the Reynolds-Averaged Navier-Stokes (RANS) method. The interaction between the submarine and the free surface is captured by using the Volume of Fluid (VOF) method. The motion of submarine and rudder is achieved through overset grid technology, while the rotating propeller is modeled by using the body force model. Numerical simulations of the turning circle test are performed for those conditions, and the variation law of the turning motion parameters at different immersion depths is revealed. Based on the obtained flow field details, including free surface waveform, shedding vortices, and velocity distribution, the interaction between the self-propelled submarine and the free surface and its relationship with the submarine turning characteristics are explored.

本文对近水面自航潜艇的转弯运动进行了数值研究。采用reynolds - average Navier-Stokes （RANS）方法求解潜艇周围的湍流。利用流体体积法（VOF）捕捉潜艇与自由表面的相互作用。潜艇和方向舵的运动通过反置网格技术实现，螺旋桨的运动采用体力模型建模。在这些条件下进行了回转试验的数值模拟，揭示了不同浸泡深度下回转运动参数的变化规律。基于所获得的流场细节，包括自由面波形、脱落涡和速度分布，探讨了自主潜艇与自由面相互作用及其与潜艇转向特性的关系。

引用次数: 0

A framework and application for dynamic assessment of ship equipment based on multi-source data fusion and digital twins 基于多源数据融合和数字孪生的舰船装备动态评估框架及应用

IF 3.9 3区工程技术 Q2 ENGINEERING, MARINE

International Journal of Naval Architecture and Ocean Engineering

Pub Date : 2026-01-01 Epub Date: 2026-02-12 DOI: 10.1016/j.ijnaoe.2026.100746

Nanzhe Song, Shaojuan Su, Pengyao Yu, Hongda Wang

Addressing diagnostic challenges in complex marine environments (high humidity, high salinity, multi-source interference, diverse fault types), this study uses a marine centrifugal fan to construct an intelligent condition assessment framework integrating digital twin and multi-source heterogeneous sensing. Vibration, visual, and speed data are synchronised and mapped to a lightweight digital twin for dynamic state perception. A fusion strategy based on robust Mahalanobis distance and convolutional neural networks identifies six fault modes (weighted F1 = 0.9965). A visual detection model tailored for ship compartments achieves [email protected] of 0.861 (cracks) and 0.827 (corrosion). Multi-modal results enhance adaptability and robustness to offshore conditions. Interactive programs enable real-time monitoring and fault visualisation. Experiments confirm high diagnostic accuracy, fast response, and efficient deployment, supporting intelligent ship equipment condition management.

针对复杂海洋环境（高湿、高盐度、多源干扰、多种故障类型）下的诊断挑战，本研究利用海洋离心风机构建了集成数字孪生和多源异构传感的智能状态评估框架。振动、视觉和速度数据是同步的，并映射到一个轻量级的数字双胞胎动态状态感知。基于鲁棒马氏距离和卷积神经网络的融合策略识别出6种故障模式（加权F1 = 0.9965）。为船舶舱室量身定制的视觉检测模型[email protected]达到0.861（裂缝）和0.827（腐蚀）。多模态结果增强了对海上条件的适应性和鲁棒性。交互式程序实现实时监控和故障可视化。实验验证了诊断准确性高、响应速度快、部署效率高，支持船舶设备状态智能管理。

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引用次数: 0

A method for transferring piping designs using past project data in shipbuilding 一种利用造船中以往项目数据传递管道设计的方法

IF 3.9 3区工程技术 Q2 ENGINEERING, MARINE

International Journal of Naval Architecture and Ocean Engineering

Pub Date : 2026-01-01 Epub Date: 2026-03-02 DOI: 10.1016/j.ijnaoe.2026.100755

Min-Chul Kong , Myung-Il Roh , In-Su Han , Seong-Won Choi , Jeongyeon Kim

Ship piping design requires arranging many interconnected pipes within confined spaces while satisfying connectivity and collision constraints. This study proposed a data-driven method for transferring 3D pipe routes from past ship projects to a new target ship via a two-stage workflow: similar-system retrieval and route transfer with geometric adjustment. First, P&IDs (Piping and Instrumentation Diagrams) were converted into system graphs consisting of equipment nodes and connection edges. System similarity was computed by embedding graphs with graph2vec and ranking candidates by cosine similarity to retrieve past systems structurally closest to the target system. Second, the retrieved system's historical 3D routes were normalized by principal ship dimensions and used to construct a routing space. To reflect both proximity and segment orientation, DBSCAN (Density-Based Spatial Clustering of Applications with Noise) was extended with an angular-distance term between segment direction vectors, and the resulting clusters were merged and scaled to the target ship geometry. A past pipe centerline was then transferred into the routing space and adjusted by solving a constrained optimization with GA (Genetic Algorithm), where bend nodes are treated as design variables and their motion is restricted to preserve the original route shape. Feasibility was evaluated using a SphereCast-based collision penalty against hull and obstacle colliders. By enabling retrieval-conditioned reuse of proven route patterns and automated collision-aware adjustment within a learned routing space, the proposed method supports rapid generation of feasible initial piping layouts for new ship projects while reducing manual trial-and-error in early-stage routing.

船舶管道设计要求在满足连通性和碰撞约束的前提下，在密闭空间内布置许多相互连接的管道。本研究提出了一种数据驱动的方法，通过两阶段的工作流程：相似系统检索和具有几何调整的路线转移，将过去船舶项目的三维管道路线转移到新的目标船上。首先，将管道和仪表图（P& id）转换成由设备节点和连接边组成的系统图。系统相似度通过使用graph2vec嵌入图来计算，并通过余弦相似度对候选对象进行排序，以检索结构上最接近目标系统的过去系统。其次，将检索到的系统历史三维航路按船舶主维进行归一化，构建航路空间；为了同时反映接近度和航段方向，DBSCAN（基于噪声的密度空间聚类应用）在航段方向向量之间加入角距离项，并将聚类合并并缩放到目标船舶的几何形状。然后将过去的管道中心线转移到路由空间中，并通过求解GA（遗传算法）的约束优化进行调整，其中弯曲节点被视为设计变量，其运动被限制以保持原始路径形状。使用基于spherecast的碰撞惩罚对船体和障碍物碰撞器进行可行性评估。通过对已验证的路线模式进行检索条件复用，并在已学习的路线空间内进行自动碰撞感知调整，该方法支持为新船项目快速生成可行的初始管道布局，同时减少早期路线的人工试错。

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引用次数: 0

A study on aiming control and validation of a reinforcement learning-based fire monitor in maritime environments 海上环境下基于强化学习的火灾监视器瞄准控制与验证研究

IF 3.9 3区工程技术 Q2 ENGINEERING, MARINE

International Journal of Naval Architecture and Ocean Engineering

Pub Date : 2026-01-01 Epub Date: 2026-02-23 DOI: 10.1016/j.ijnaoe.2026.100752

Hyukcheon Kwon , Wonsun Ruy , Sangik Park , Hyuk Lee

With the growing interest in autonomous ships, there has been an increasing demand for intelligent fire suppression systems that can operate reliably even under irregular sea conditions. This study proposes an autonomous aiming control approach for a fire monitor, designed to optimize its targeting performance through reinforcement learning (RL). A virtual environment was created using the Unity physics engine, which simulated ship motion and the dynamic behavior of discharged water while reflecting variations in sea states and discharge pressure. The proposed RL-based model was trained to improve aiming efficiency by observing the vessel's motion and nozzle pressure data measured by an inertial measurement unit (IMU) sensor and pressure sensor. The effectiveness of the model was verified through full-scale experiments conducted on an actual vessel operating under sea state about 3 condition. Experimental observations confirmed that the system maintained stable and precise fire-targeting performance in a real maritime environment. These results suggest that the proposed RL-based control approach can contribute to the automation of fire response operations for future unmanned autonomous ships.

随着人们对自主船舶的兴趣日益浓厚，对智能灭火系统的需求也越来越大，这种系统即使在不规则的海况下也能可靠地运行。本研究提出了一种火灾监视器的自主瞄准控制方法，旨在通过强化学习（RL）优化其瞄准性能。使用Unity物理引擎创建虚拟环境，模拟船舶运动和排放水的动态行为，同时反映海况和排放压力的变化。通过惯性测量单元（IMU）传感器和压力传感器测量的船舶运动和喷嘴压力数据，对基于rl的模型进行训练，以提高瞄准效率。通过实际船舶在3种工况下的全尺寸试验，验证了该模型的有效性。实验观察证实，该系统在真实的海上环境中保持稳定和精确的火力瞄准性能。这些结果表明，提出的基于rl的控制方法可以为未来无人驾驶自主船舶的火灾响应操作自动化做出贡献。

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引用次数: 0

A systematic study on the influence of scale, hull roughness, and draft on form factor estimation 系统研究了比例尺、船体粗糙度和吃水对形状因子估计的影响

IF 3.9 3区工程技术 Q2 ENGINEERING, MARINE

International Journal of Naval Architecture and Ocean Engineering

Pub Date : 2026-01-01 Epub Date: 2026-01-03 DOI: 10.1016/j.ijnaoe.2025.100739

Minas Argyros , Simone Mancini , Kadir Burak Korkmaz , Arash Eslamdoost

In recent years, considerable attention has been given to the prediction of form factor of ships and the associated scale effects, as the accuracy of such estimations has come under scrutiny. This paper explores the discrepancies between model-scale and full-scale form factor predictions derived from CFD simulations using a newly developed approach known as the 2-

k

method. This method enhances the precision of form factor evaluation, particularly when applied at full scale, showing notable improvements for hulls with wetted transoms. This study tests the hypothesis of 2-k and transom correction methods with different numerical tools and methods. It reveals a strong dependence of the form factor on grid resolution across different scales, while aligning well with findings reported in the literature. Additionally, a sensitivity analysis based on uniformly distributed surface roughness is performed. The 2-

k

method is also applied to systematically varied transom submergence conditions, demonstrating consistent form factor trends across both model and full scales. Furthermore, when evaluating draft variations, the method yields results that more closely match experimental data. These findings suggest that the 2-

k

method is a reliable tool for estimating the form factor in scenarios involving complex turbulent flow, such as in the wake of the transom.

近年来，由于这种估计的准确性受到审查，对船舶形状因素的预测和有关的规模效应给予了相当大的注意。本文探讨了模型尺度和全尺寸外形因子预测之间的差异，这些预测来自CFD模拟，使用了一种新开发的方法，即2k方法。这种方法提高了形状因子评估的精度，特别是在全尺寸应用时，对于带有湿式横梁的船体显示出显着的改进。本文采用不同的数值工具和方法对2-k假设和横截面校正方法进行了检验。它揭示了形状因素对不同尺度网格分辨率的强烈依赖，同时与文献报道的结果很好地一致。此外，基于均匀分布的表面粗糙度进行了灵敏度分析。2-k方法也适用于系统变化的横贯淹没条件，在模型和全尺寸中显示一致的形状因素趋势。此外，当评估草稿变化时，该方法产生的结果更接近实验数据。这些发现表明，2-k方法是一种可靠的工具，用于估计涉及复杂湍流的情况下的形状因子，例如在尾梁的尾迹中。

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引用次数: 0