International Journal of Naval Architecture and Ocean Engineering最新文献

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 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

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 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

Performance evaluation of a 15 MW semi-submersible floating offshore wind turbine with a synthetic fiber mooring system 采用合成纤维系泊系统的15mw海上半潜式浮式风力机性能评价

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.2025.100734

Frederick Gavin , Chungkuk Jin , Sewon Kim , Woo Chul Chung , MooHyun Kim

The present study investigates the influence of permanent elongation and dynamic stiffness variation in polyester ropes on the dynamic and structural behaviors of 15-MW taut-moored semi-submersible floating offshore wind turbine (FOWT) platforms. Numerical models of FOWTs were developed, incorporating the permanent elongation and dynamic stiffness variations of polyester ropes under various environmental conditions using the Syrope methodology. Three mooring configurations were analyzed: chain-only and chain–polyester–chain systems, with and without updates for permanent elongation and dynamic stiffness. Results were assessed through statistical parameters and time histories of platform motions and hub accelerations as dynamic responses and mooring tensions and tower-base moments as structural responses. The findings reveal that accounting for permanent elongation and stiffness variation amplifies global motions and structural responses compared to cases neglecting these effects. In taut-mooring configurations, the observed behavioral changes are associated with slack-taut transitions and snap loading phenomena, markedly intensified when considering elongation and dynamic stiffness.

本文研究了聚酯绳的永久伸长和动态刚度变化对15mw系泊半潜式海上风电平台动力和结构性能的影响。采用Syrope方法建立了FOWTs的数值模型，结合了不同环境条件下聚酯绳的永久伸长率和动态刚度变化。研究人员分析了三种系泊结构：纯链系泊和链-聚酯链系泊，以及有无更新的永久伸长率和动态刚度。通过平台运动和轮毂加速度作为动力响应的统计参数和时间历史，以及系泊张力和塔基力矩作为结构响应来评估结果。研究结果表明，与忽略这些影响的情况相比，考虑永久伸长率和刚度变化放大了整体运动和结构响应。在拉紧系泊配置中，观察到的行为变化与松弛-拉紧过渡和弹跳加载现象有关，当考虑伸长率和动刚度时，这种变化明显加剧。

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引用次数: 0

A RAG-based Q&A system for ship regulations applying domain adaptation 基于区域自适应的船舶规则问答系统

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.2025.100735

In-Su Han , Myung-Il Roh , Min-Chul Kong

Various international organizations and classification societies have established extensive regulations to enhance the safety and reliability of ships. These regulations are continuously revised and updated to keep pace with technological advancements, the increasing size of ships, and the tightening of environmental regulations in the shipbuilding and maritime industry. The key contents of regulations are often conveyed through text, as well as interrelated equations and tables. Due to the complexity of these formats and the inherent difficulty of the regulatory content itself, users require considerable time, effort, and a high level of expertise to retrieve and interpret the necessary information accurately. This study proposed a Q&A (Question-and-Answer) system for ship regulations utilizing RAG (Retrieval-Augmented Generation) to address these challenges. The proposed system comprises a framework that retrieves relevant information from a large-scale database and generates reliable answers tailored to the user's query intent. To achieve this, we constructed ship regulations into a database optimized for searchability and incorporated hierarchical structures to improve search accuracy. A search module was implemented based on semantic analysis techniques to retrieve the most relevant rules effectively. An answer generation module was also implemented to produce appropriate answers grounded in the retrieved rules. Especially, a domain adaptation technique was applied to a general-purpose model, enabling the system to clearly understand the specialized terminology and context within the domain of ship regulations. The Q&A system supports users in quickly navigating ship regulations, facilitating clear comprehension and practical application of the information. The proposed system was applied to the regulations of the Korean Register, demonstrating its capability to promptly and accurately retrieve rules related to user queries and generate reliable answers.

各种国际组织和船级社已经制定了广泛的法规来提高船舶的安全性和可靠性。这些法规不断修订和更新，以跟上技术进步，船舶规模的增加，以及造船和海事行业环境法规的收紧。规章的主要内容往往通过文字以及相关的方程式和表格来传达。由于这些格式的复杂性和监管内容本身固有的难度，用户需要大量的时间、精力和高水平的专业知识来准确地检索和解释必要的信息。本研究提出了一个利用RAG（检索增强生成）的船舶法规问答系统来解决这些挑战。该系统包括一个从大型数据库中检索相关信息的框架，并根据用户的查询意图生成可靠的答案。为了实现这一目标，我们将船舶规则构建到一个优化了可搜索性的数据库中，并采用分层结构来提高搜索精度。实现了基于语义分析技术的搜索模块，有效检索相关度最高的规则。还实现了一个答案生成模块，以根据检索到的规则生成适当的答案。特别地，将领域自适应技术应用于通用模型，使系统能够清晰地理解船舶法规领域内的专业术语和上下文。Q&；A系统支持用户快速导航船舶法规，促进对信息的清晰理解和实际应用。将该系统应用于《韩国登记簿》的规章制度，证明了该系统能够迅速准确地检索与用户查询有关的规则，并产生可靠的答案。

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引用次数: 0

A numerical study on self-propulsion performance of the 66k DWT bulk carrier in low-speed calm water and regular wave conditions 66k DWT散货船在低速静水和规则波条件下自推进性能的数值研究

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 DOI: 10.1016/j.ijnaoe.2025.100729

Myeong-Min Kim , Kwang-Jun Paik , Soon-Hyun Lee , Jae-Hyeon An , Soo-Yeon Kwon

This study evaluated the self-propulsion performance of the K-Supramax (66,000 DWT) bulk carrier in calm water and regular wave conditions at the design speed (14.5 knots) and 4.0 knots. Using the virtual disk method in Computational Fluid Dynamics (CFD) analysis, the self-propulsion characteristics were validated based on KRISO's experimental data, and these characteristics were applied to analyze the self-propulsion performance under wave conditions. Major self-propulsion factors, such as the thrust deduction factor and effective wake fraction, were analyzed to examine the impact of wave conditions on propulsion efficiency. Additionally, the differences in the delivered power (DHP) estimated by the CFD simulation and the load variation method were analyzed according to wave conditions. This research identified the impact of added resistance due to waves on self-propulsion performance, demonstrating that the effect of added resistance was more significant at 4.0 knots than at 14.5 knots. This study provides fundamental data for analyzing self-propulsion performance under wave conditions and establishes an important foundation for future research on estimating the minimum propulsion power under both design and low-speed conditions.

本研究以设计航速（14.5节）和4.0节分别评估了K-Supramax （66,000 DWT）散货船在静水和规则波条件下的自推进性能。利用计算流体动力学（CFD）分析中的虚拟磁盘方法，基于KRISO的实验数据验证了自推进特性，并将这些特性应用于波浪工况下的自推进性能分析。分析了主要的自推进因素，如推力扣除系数和有效尾迹分数，以检验波浪条件对推进效率的影响。此外，根据不同的波浪条件，分析了CFD模拟和负荷变化法估算的输出功率（DHP）的差异。该研究确定了波浪产生的附加阻力对自推进性能的影响，表明在4.0节时，附加阻力的影响比在14.5节时更为显著。该研究为波浪工况下的自推进性能分析提供了基础数据，为今后设计工况和低速工况下的最小推进功率估算研究奠定了重要基础。

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引用次数: 0

Comparative study on the hydrodynamic flow characteristics around the BB2 submarine using RANS and PANS turbulence models under straight and drift conditions 利用RANS和PANS湍流模型对BB2潜艇在直流和漂移条件下的水动力流动特性进行了对比研究

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 DOI: 10.1016/j.ijnaoe.2025.100702

Changhun Lee , Hyeri Lee , I Ketut Aria Pria Utama , Woochan Seok

This study presents a comparative computational analysis of the hydrodynamic flow characteristics around the Joubert BB2 submarine using Reynolds-Averaged Navier–Stokes (RANS) and Partially-Averaged Navier–Stokes (PANS) turbulence models. Simulations were performed under two representative operating conditions: straight-ahead motion and 10° drift. The numerical framework was validated against MARIN benchmark data, focusing on the total resistance and axial velocity distributions at the propeller plane. Comparative analyses demonstrated that the PANS model better captures the spatial development of turbulent kinetic energy, along with asymmetric wake features and intricate vortex interactions. The analysis included detailed comparisons of wall shear stress, axial velocity, vorticity, vortex structure and turbulent kinetic energy distributions. In particular, the PANS model demonstrated superior capability in capturing flow separation, vortex development, and wake evolution under asymmetric inflow conditions. Under both conditions, the PANS model captured more coherent vortex structures and more pronounced variations in velocity, while the RANS model exhibited overpredicted turbulence energy and more diffused wake characteristics. These findings suggest that the PANS model offers a physically consistent and computationally efficient alternative to RANS for simulating unsteady and asymmetric flows around submerged bodies, particularly in scenarios where wake dynamics critically influence propulsion and maneuvering performance.

本文采用reynolds - average Navier-Stokes （RANS）和部分平均Navier-Stokes （PANS）湍流模型对Joubert BB2潜艇周围的水动力流动特性进行了对比计算分析。在两种典型工况下进行了仿真：直线运动和10°漂移。针对MARIN基准数据对数值框架进行了验证，重点研究了螺旋桨平面的总阻力和轴向速度分布。对比分析表明，PANS模型更好地捕捉了湍流动能的空间发展，以及不对称尾迹特征和复杂的涡相互作用。分析包括壁面剪应力、轴向速度、涡量、涡结构和湍流动能分布的详细比较。特别是，在非对称入流条件下，PANS模型在捕捉流动分离、涡发展和尾迹演变方面表现出了优越的能力。在这两种情况下，PANS模型捕捉到了更连贯的涡结构和更明显的速度变化，而RANS模型则表现出湍流能量的高估和更扩散的尾迹特征。这些发现表明，PANS模型为模拟水下物体周围的非定常和非对称流动提供了一种物理上一致且计算效率高的替代方案，特别是在尾流动力学严重影响推进和机动性能的情况下。

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引用次数: 0

Hull form reconstruction from insufficient data conforming to hydrostatic constraints 根据不充分的符合流体静力约束的数据重建船体形状

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.2025.100732

Dayeon Jeong , Min-Jae Oh , Jinyoung Park

Classification societies perform stability analysis based on offsets submitted by shipyards and verify the results. However, in many practical situations, the hull form data required for hydrostatic evaluation is insufficient. This commonly occurs during the stability reassessment of retrofitted or damaged ships, or when original design data are limited due to confidentiality or unavailable from foreign shipyards. As a result, classification societies are often required to reconstruct the hull form using only partial information. To address this issue this study proposes a reverse-engineering method that regenerates hull forms by introducing a novel interpolation approach with area constraints so that hydrostatic requirements are inherently satisfied. Specifically, waterlines are generated at each draft level with their area constrained to match the

C_{W P}

and this guarantees the correct displacement. By maintaining waterline consistency across drafts additional hydrostatic constraints such as the

C_{P}

,

L C B

,

V C B

are simultaneously satisfied. This mathematically grounded perspective that treats the

C_{W P}

-based area as a governing constraint provides a new way to couple hydrostatic data with geometric reconstruction and move beyond manual adjustments. The proposed method was validated on three ship types, and the results demonstrated its effectiveness in producing reliable hull forms for performance analysis while significantly reducing both time and dependency on expert judgment.

船级社根据船厂提交的补偿进行稳定性分析，并对结果进行验证。然而，在许多实际情况下，水静力评估所需的船体形状数据是不足的。这通常发生在改装或损坏船舶的稳定性重新评估期间，或者由于保密或无法从外国造船厂获得原始设计数据而受到限制时。因此，船级社通常只需要使用部分信息来重建船体形状。为了解决这一问题，本研究提出了一种逆向工程方法，通过引入一种具有面积约束的新颖插值方法来再生船体形状，从而内在地满足流体静力要求。具体来说，在每个吃水水平上生成水线，其面积受限制以匹配CWP，这保证了正确的位移。通过保持水线的一致性，可以同时满足额外的流体静力约束，如CP、LCB、VCB。这种基于数学的视角将基于cwp的区域视为控制约束，提供了一种将流体静力学数据与几何重建相结合的新方法，无需手动调整。该方法在三种船型上进行了验证，结果表明，该方法可以有效地为性能分析生成可靠的船体形状，同时大大减少了时间和对专家判断的依赖。

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引用次数: 0

Development of a heat transfer analysis program by an efficient and simplified numerical technique: Application to LNGC 基于高效简化数值技术的换热分析程序的开发：在液化石油气中的应用

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 DOI: 10.1016/j.ijnaoe.2025.100736

Chang Hwan Jang , Shin Hyung Kim , Nak-Kyun Cho , Seungjun Kim , Do Kyun Kim

Heat transfer analysis in ships handling LNG as cargo or fuel at extremely low temperatures has two purposes, i.e., 1) to select steel grades based on temperature distribution to protect the hull structure from extremely low-temperature cargo and 2) to obtain the boil-off rate (BOR) by calculating the amount of heat flowing into the cargo hold. For a typical LNG carrier (LNGC), the heat transfer model can be simplified by introducing the overall heat transfer coefficient, which enables easy and fast heat transfer analysis. However, as various ships and containers for transporting and storing cryogenic cargoes or fuels such as LNG were developed, a heat transfer analysis program that could be applied to various and complex shapes became necessary. Methods and programs considering various hull structures and complex shapes have been proposed and developed. The concept of the finite element method was introduced to consider various shapes in heat transfer analysis. The hull and surrounding space are divided into panels and spaces, and heat transfer problems can be solved in 2D or 3D by defining line, plane, and volume elements. The basic heat transfer equations were derived by defining a unit heat transfer model consisting of one panel and two spaces and a unit heat balance model consisting of one space and multiple panels. The heat transfer equations of the unit models were assembled into the equations of the entire model, and the equations were solved using matrix operations. Heat transfer analysis for LNG ships was performed using the developed program to calculate temperature distribution and BOR. Analysis models for various types of LNG ships were created to verify the applicability and usability of the program. Additionally, we reviewed issues that may be considered in the heat transfer analysis of ships.

在极低温下，LNG作为货物或燃料运输船舶的传热分析有两个目的：1)根据温度分布选择钢种，以保护船体结构免受极低温货物的影响；2)通过计算流入货舱的热量来获得蒸发率（BOR）。对于典型的LNG运输船（LNGC），可以通过引入总传热系数来简化传热模型，从而实现简单快速的传热分析。然而，随着用于运输和储存低温货物或LNG等燃料的各种船舶和集装箱的发展，一种可以应用于各种复杂形状的传热分析程序变得必要。已经提出并开发了考虑各种船体结构和复杂形状的方法和程序。引入有限元法的概念，在传热分析中考虑各种形状。船体和周围空间被划分为面板和空间，传热问题可以通过定义线、平面和体积元素在2D或3D中解决。通过定义由一个面板和两个空间组成的单位传热模型和由一个空间和多个面板组成的单位热平衡模型，推导了基本的传热方程。将单元模型的传热方程组合成整体模型的传热方程，采用矩阵运算求解。利用开发的程序对LNG船舶进行了传热分析，计算了温度分布和BOR。建立了不同类型LNG船舶的分析模型，验证了该方案的适用性和可用性。此外，我们回顾了船舶传热分析中可能考虑的问题。

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引用次数: 0

Corrigendum to ‘A comprehensive review of foundation designs for fixed offshore wind turbines’ [Int. J. Nav. Archit. Ocean Eng. 17 (2025) 100643] 《固定式海上风力涡轮机基础设计的全面审查》的勘误表[英]。j . Nav。Archit。海洋工程，17 (2025)100643]

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.2026.100743

Yun-jae Kim , Jin Seok Lim , Hae Jong Kim , Sung-Woong Choi

引用次数: 0