International Journal of Naval Architecture and Ocean Engineering最新文献

Data-driven model for predicting cargo tank pressure of an LNG carrier considering environmental effects 考虑环境影响的LNG运输船货舱压力预测数据驱动模型

IF 3.9 3区工程技术 Q2 ENGINEERING, MARINE

International Journal of Naval Architecture and Ocean Engineering

Pub Date : 2025-12-02 DOI: 10.1016/j.ijnaoe.2025.100713

Hyun Soo Kim , Myung-Il Roh

The utilization of natural gas is expanding as part of efforts to reduce greenhouse gas (GHG) emissions. Natural gas is typically liquefied at cryogenic temperatures in order to enhance the efficiency of maritime transport. When these cryogenic cargoes are shipped, BOG (Boil-Off Gas) is generated by the external heat and wave-induced ship motion. Proper management of BOG is critical to maintaining the cargo tank pressure within a safe operational range. In the case of LNG (Liquefied Natural Gas) carriers, BOG is used as fuel for main engines and generator engines, with any surplus being burned in the GCU (Gas Combustion Unit) or reliquefied by a reliquefaction system. Accurate prediction of BOG generation and cargo tank pressure is therefore essential for optimizing reliquefaction system operations and voyage planning. Although various experimental and CFD-based studies have been conducted, it remains challenging to capture the complex, irregular characteristics of real marine environments, particularly the effects of ship motion and sloshing. This study presents a framework for developing a data-driven model that predicts cargo tank pressure in LNG carriers. The data-driven model is based on long-term operation data from a 174K-class LNG carrier, enabling consideration of the combined effects of BOG consumption, reliquefaction performance, and marine environmental conditions on cargo tank pressure. The variables related to cargo tank pressure are derived from ship operation, BOG consumption, and marine environmental conditions. Several regression and machine learning algorithms were compared to identify the most effective predictive model. The model's accuracy was verified by comparing predicted values with actual measurements from an LNG carrier that had been in operation for 2 years, and the results confirmed high predictive accuracy. This approach provides a practical framework for data-driven cargo tank pressure prediction and contributes to improving energy efficiency and reducing GHG emissions in LNG carrier operations.

作为减少温室气体（GHG）排放努力的一部分，天然气的利用正在扩大。为了提高海上运输的效率，天然气通常在低温下液化。当这些低温货物运输时，BOG（沸腾气体）是由外部热量和波浪引起的船舶运动产生的。正确的BOG管理对于将液货舱压力保持在安全运行范围内至关重要。在LNG（液化天然气）运输船的情况下，BOG被用作主机和发电机发动机的燃料，任何剩余的燃料都在GCU（气体燃烧单元）中燃烧或通过再液化系统再液化。因此，准确预测BOG生成和货舱压力对于优化再液化系统操作和航行计划至关重要。尽管已经进行了各种实验和基于cfd的研究，但要捕捉真实海洋环境的复杂、不规则特征，特别是船舶运动和晃动的影响，仍然具有挑战性。本研究提出了一个用于开发数据驱动模型的框架，该模型可以预测LNG运输船的货舱压力。数据驱动模型基于一艘174k级LNG运输船的长期运行数据，考虑了BOG消耗、再液化性能和海洋环境条件对货油舱压力的综合影响。与货舱压力相关的变量来自船舶操作、BOG消耗和海洋环境条件。比较了几种回归和机器学习算法，以确定最有效的预测模型。通过将预测值与一艘运行了2年的LNG运输船的实际测量值进行比较，验证了该模型的准确性，结果证实了预测的准确性。该方法为数据驱动的货舱压力预测提供了实用框架，有助于提高LNG运输船运营中的能源效率和减少温室气体排放。

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引用次数: 0

Numerical and experimental investigation of an Inertial Tilting hybrid wave energy converter for powering small-scale marine systems 小型海洋系统惯性倾斜混合波能转换器的数值与实验研究

IF 2.3 3区工程技术 Q2 ENGINEERING, MARINE

International Journal of Naval Architecture and Ocean Engineering

Pub Date : 2025-01-01 DOI: 10.1016/j.ijnaoe.2025.100658

Chongfei Sun , Huaiyu Teng , Xiaoyan Ma , Hailong Chen , Liming Sun , Cun Shao , Fei Cao , Hengxu Liu

The increasing global demand for marine resource exploration, maritime rights protection, and deep-sea engineering applications highlights the need for the diversification of marine engineering equipment and the expansion of its deep-sea capabilities, presenting significant technical and economic value. As the use of small-scale marine engineering equipment in deep-sea environments becomes more prevalent, optimizing energy supply methods for such equipment is critical to ensure their durability and efficiency in complex marine conditions. This paper proposes an Inertial Tilting Electromagnetic-Triboelectric Hybrid Energy Converter (ITHEC), which efficiently harvests energy from ocean waves to power small marine engineering devices. A comprehensive design and optimization framework was developed for this energy converter. This framework was based on theoretical analysis and simulations of structural dynamics and characteristics. Validation experiments were conducted using a custom-built structural characteristics testing platform. The results showed that under horizontal harmonic motion excitation with an amplitude of d = 60 mm and a frequency of f = 1.5Hz, the open-circuit voltages of the triboelectric nanogenerator (TENG) and electromagnetic generator (EMG) reached 60V and 0.23V, respectively, with short-circuit currents of 1.3 μA and 2.2 mA, and peak power densities of 1.18 mW/m² and 0.51 mW/m². When arrayed, the hybrid energy converter can meet the operating current requirements of small marine sensors. This study offers an innovative solution for energy supply challenges in small marine equipment and establishes the practical viability of hybrid power systems for marine energy harvesting.

全球对海洋资源勘探、海洋权益保护和深海工程应用的需求日益增长，凸显了海洋工程设备多样化和深海能力扩展的需求，呈现出重大的技术和经济价值。随着小型海洋工程设备在深海环境中的使用越来越普遍，优化此类设备的能源供应方法对于确保其在复杂海洋条件下的耐久性和效率至关重要。本文提出了一种惯性倾斜电磁-摩擦电混合能量转换器（ITHEC），它可以有效地从海浪中收集能量，为小型海洋工程设备提供动力。建立了该能量转换器的综合设计与优化框架。该框架基于理论分析和结构动力学特性仿真。在定制的结构特性测试平台上进行了验证实验。结果表明，在幅值为d = 60 mm、频率为f = 1.5Hz的水平谐波激励下，摩擦纳米发电机（TENG）和电磁发电机（EMG）的开路电压分别达到60V和0.23V，短路电流分别为1.3 μA和2.2 mA，峰值功率密度分别为1.18 mW/m2和0.51 mW/m2。混合能量转换器阵列后，可以满足小型船用传感器的工作电流要求。该研究为小型船舶设备的能源供应挑战提供了一种创新的解决方案，并建立了用于海洋能源收集的混合动力系统的实际可行性。

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引用次数: 0

Numerical simulations and large-scale experimental research into air-lifting system for deep-sea mining 深海采矿气举系统数值模拟与大型试验研究

IF 2.3 3区工程技术 Q2 ENGINEERING, MARINE

International Journal of Naval Architecture and Ocean Engineering

Pub Date : 2025-01-01 DOI: 10.1016/j.ijnaoe.2025.100656

JianYu Xiao , Zhuang Kang , Jing Leng , Ming Chen , Jun Liu

The deep seabed harbors abundant mineral resources. To achieve the economic viability of deep-sea mining, the efficiency of polymetallic nodule lifting is critical. In this study, we investigate the performance of air-lifting systems, which is a key component of deep-sea mining operations. Through two-phase flow simulations, we establish the relationship between the air-injection velocity and water-lifting velocity and validate the experimental data. We constructed a large-scale air-lifting system in a 20-m-deep water tank to explore the feasibility and energy efficiency of lifting water and nodules under varying air-injection velocities and depths. In detailed energy efficiency calculations, we determined the optimal operational parameters which provide novel insights into the design and optimization of deep-sea mining lifting systems. The experimental data and findings offer valuable references for future system designs that can enhance operational stability and economic feasibility.

深海海底蕴藏着丰富的矿产资源。为了实现深海采矿的经济可行性，多金属结核的提升效率至关重要。在本研究中，我们研究了空气提升系统的性能，这是深海采矿作业的关键组成部分。通过两相流模拟，建立了注气速度与提水速度的关系，并对实验数据进行了验证。我们在20m深的水箱中构建了大型气举系统，探索在不同的注气速度和深度下举升水和结核的可行性和能效。在详细的能源效率计算中，我们确定了最佳操作参数，为深海采矿提升系统的设计和优化提供了新的见解。实验数据和研究结果为今后系统的设计提供了有价值的参考，可以提高系统的运行稳定性和经济可行性。

引用次数: 0

Experiment and modeling of submarine emergency rising motion using free-running model 基于自由运行模型的潜艇应急上升运动实验与建模

IF 2.3 3区工程技术 Q2 ENGINEERING, MARINE

International Journal of Naval Architecture and Ocean Engineering

Pub Date : 2025-01-01 DOI: 10.1016/j.ijnaoe.2024.100641

Jooho Lee, Seonhong Kim, Jihwan Shin, Jaemoon Yoon, Jinheong Ahn, Minjae Kim

Development of submarine and its safe operational envelope requires an understanding of motion characteristics including emergency rising motion. In this study, the emergency rising motion is investigated using submarine free-running model equipped with ballast systems. The emergency rising test was conducted according to the initial vehicle speed, yaw rate, depth, ballast water discharge ratio and time interval between bow and stern ballast systems. Experimental results reveal that the maximum pitch angle before surface is affected by initial velocity and the operation conditions of ballast systems. In addition, excessive roll occurs after the surface when the submarine passes through the water surface at a negative pitch angle. Furthermore, the system parameters that comprise the emergency rising model are estimated using the collected test data. The identified model is verified by comparing emergency rising simulation with the free-running model test results.

潜艇及其安全操作包线的发展需要了解包括紧急上升运动在内的运动特性。本文采用装有压载系统的潜艇自由运行模型，研究了潜艇的应急上升运动。根据船舶初始航速、横摆角速度、深度、压载水排放比和船首尾压载系统间隔时间进行应急上升试验。实验结果表明，初始速度和压载系统运行条件对最大俯仰角有一定的影响。此外，当潜艇以负俯仰角通过水面时，水面后会出现过大的横摇。此外，利用收集到的试验数据估计了构成应急上升模型的系统参数。通过应急上升仿真与自由运行模型试验结果的对比，验证了所识别的模型的正确性。

引用次数: 0

A comprehensive review of foundation designs for fixed offshore wind turbines 固定式海上风力发电机基础设计综述

IF 2.3 3区工程技术 Q2 ENGINEERING, MARINE

International Journal of Naval Architecture and Ocean Engineering

Pub Date : 2025-01-01 DOI: 10.1016/j.ijnaoe.2025.100643

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

In the present study, technical challenges and their corresponding solutions for each type of foundation—gravity-based, monopile, jacket, tripod, and suction bucket—used in wind turbines were addressed with consideration to different water depths. Along with presenting challenges and their solutions for each foundation, the present study proposed optimizing solutions and methods for addressing these challenges, including numerical approaches and empirical methods derived from field testing. These include enhancing structural stability, improving installation efficiency, and utilizing advanced structural analysis techniques to predict and mitigate environmental impacts. Finally, research cases demonstrating improvements in foundations through shape modifications are summarized. This paper focuses on addressing and proposing an optimal design approach to achieve cost reduction, improved stiffness, and weight minimization. Notably, hybrid foundations incorporating friction wheels achieved a 300% increase in ultimate bearing capacity, while optimization techniques accounting for environmental loads resulted in approximately a 38.24% reduction in foundation weight.

本文针对风力发电机组中使用的重力式基础、单桩式基础、夹套式基础、三脚架式基础、吸力桶式基础等不同类型的基础，针对不同的水深，分析了其技术难点及解决方案。除了提出每个基础面临的挑战及其解决方案外，本研究还提出了应对这些挑战的优化解决方案和方法，包括数值方法和来自现场测试的经验方法。这些措施包括增强结构稳定性，提高安装效率，以及利用先进的结构分析技术来预测和减轻环境影响。最后，总结了通过形状修改改善地基的研究案例。本文的重点是解决和提出一个优化的设计方法，以实现成本降低，提高刚度和重量最小化。值得注意的是，结合摩擦轮的混合地基的极限承载能力提高了300%，而考虑环境载荷的优化技术则使地基重量减少了38.24%。

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引用次数: 0

Statistical study of cascade hydrodynamics and cavitation dynamics in propulsion pumps 推进泵叶栅水动力与空化动力学的统计研究

IF 2.3 3区工程技术 Q2 ENGINEERING, MARINE

International Journal of Naval Architecture and Ocean Engineering

Pub Date : 2025-01-01 DOI: 10.1016/j.ijnaoe.2025.100665

Guoshou Zhao , Heng Liu , Rui Wu , Ning Liang , Linlin Cao

The propulsion pump is widely employed in ocean engineering to generate thrust for surface or underwater vehicles. The cascade provides a simplified way to investigate the flow dynamics inside a propulsion pump considering specific parameters such as solidity and blade stagger. This work develops the foil generation method by in-house code through parametrically controlling the maximum and its position of camber and thickness, the influence of which on the performance obtained by numerical simulation is studied by the multiple statistical regression covering linear and interaction terms. For isolated hydrofoils, the interaction of maximum thickness and its position plays a major role in determining the performance. For cascade configurations with variable foils, besides the thickness interaction terms, other terms influencing lift and drag are not unified for different angles of attack. The solidity insignificantly affects the regression terms. For the cascade with the fixed foils, the solidity, axial velocity, and incidence angle all have an impact on the cascade foil's performance. The statistical loading distributions show that the isolated foil is a typical head-loading type, and the cascade foil is a body-loading type. The cascade cavitation dynamics indicate that a higher solidity and incidence angle would depress the cavitation development owing to the adjacent foil interference. This research aims to provide an instructive guide on pump blade design.

推进泵在海洋工程中广泛应用，为水面或水下航行体提供推力。考虑到固体度和叶片交错等特定参数，叶栅为研究推进泵内部的流动动力学提供了一种简化的方法。本文通过参数化控制弯度和厚度的最大值及其位置，通过覆盖线性项和相互作用项的多元统计回归，研究了其对数值模拟所得性能的影响。对于孤立型水翼，最大厚度与其位置的相互作用是决定其性能的主要因素。对于变叶栅构型，除厚度相互作用项外，影响升力和阻力的其他项在不同迎角下并不统一。固体度对回归项影响不显著。对于固定叶栅，固体度、轴向速度和入射角都对叶栅的性能有影响。统计载荷分布表明，隔离叶型为典型的头部载荷型，叶栅叶型为体载荷型。叶栅空化动力学分析表明，较高的固体度和入射角可以抑制邻近叶干扰引起的空化发展。本研究旨在为水泵叶片的设计提供指导。

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引用次数: 0

Welding residual stress of curved plate: Development of empirical formula for predicting ultimate compressive strength 弯曲板焊接残余应力：预测极限抗压强度经验公式的发展

IF 3.9 3区工程技术 Q2 ENGINEERING, MARINE

International Journal of Naval Architecture and Ocean Engineering

Pub Date : 2025-01-01 DOI: 10.1016/j.ijnaoe.2025.100709

Yi Eun Kim , Hee Yeong Yang , Yeong Je Kim , Joo Shin Park , Dong Hun Lee , Sang Jin Kim , Do Kyun Kim

This study presents an empirical formula for predicting the ultimate compressive strength of curved plates incorporating welding-induced defects, with the objective of enhancing structural design for Ocean Mobility applications. The proposed formula uniquely considers both initial deflection and welding residual stress, two major sources of imperfection. It introduces the plate slenderness ratio (β) and the flank angle (θ, in radians) as internal variables. It enables the prediction of ultimate strength across eight representative scenarios, defined by combinations of welding direction, loading condition, initial deflection level, and residual stress distribution. The results indicate that welding residual stress can reduce the ultimate strength by up to 10 %, and the proposed formula demonstrates high accuracy with an average deviation within 0.1 % from FEM results. This research improves existing design equations by systematically incorporating the effects of welding defects, and the proposed formula may serve as a reliable tool for accurate ultimate strength assessment in the structural design of welded curved plates.

本研究提出了一个经验公式来预测含有焊接缺陷的弯曲板的极限抗压强度，目的是提高海洋机动应用的结构设计。提出的公式独特地考虑了初始挠度和焊接残余应力这两个主要的缺陷来源。引入板长细比（β）和侧翼角（θ，以弧度为单位）作为内变量。它可以通过焊接方向、加载条件、初始挠度水平和残余应力分布的组合来预测八种典型情况下的极限强度。结果表明，焊接残余应力可使极限强度降低10%，计算结果与有限元结果的平均偏差在0.1%以内，具有较高的精度。本研究通过系统地考虑焊接缺陷的影响，改进了现有的设计方程，所提出的公式可为焊接弯曲板结构设计中精确的极限强度评估提供可靠的工具。

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引用次数: 0

Safe path planning for autonomous ships based on the point of potential collision concept 基于潜在碰撞点概念的自主船舶安全路径规划

IF 3.9 3区工程技术 Q2 ENGINEERING, MARINE

International Journal of Naval Architecture and Ocean Engineering

Pub Date : 2025-01-01 DOI: 10.1016/j.ijnaoe.2025.100707

Agnieszka Lazarowska

The development of Autonomous Navigation Systems (ANS) constitutes a milestone in the process leading to the achievement of the autonomous operation of different vehicles, such as cars, aircrafts, mobile robots and ships. Obstacle avoidance is a vital task that has to be included in the process of the development of such system. The paper introduces a path planning method to be applied in the Maritime Intelligent Transportation Systems (M-ITS). The method uses the safety indicators such as the Distance at the Closest Point of Approach (DCPA), the Time to the Closest Point of Approach (TCPA), the Bow Crossing Range (BCR) and the Bow Crossing Time (BCT). The method considers the International Regulations for Preventing Collisions at Sea (COLREGs) and safety zones (domains) around target ships. The deterministic nature of the algorithm guarantees the repeatability of solutions for every run of the algorithm with the same input data and very short run-time. The approach was compared with two other algorithms, one deterministic and one heuristic. Results of 100 test cases with different complexity (simple encounters defined in the COLREGs as well as multi-ship encounters with up to 20 target ships) were compared in the paper. The algorithm searches for a solution in a cascade manner, what allows for the achievement of competitive results as compared to other algorithms maintaining short run time. These features allow to apply this collision avoidance (COLAV) method in commercial systems of autonomous ships and Unmanned Surface Vessels (USVs).

自主导航系统（ANS）的开发是实现汽车、飞机、移动机器人和船舶等不同车辆自主操作的一个里程碑。避障是该系统开发过程中必须考虑的一项重要任务。本文介绍了一种用于海上智能交通系统（M-ITS）的路径规划方法。该方法使用安全指标，如最接近点的距离（DCPA）、到最接近点的时间（TCPA）、船首穿越距离（BCR）和船首穿越时间（BCT）。该方法考虑了国际海上避碰规则（COLREGs）和目标船舶周围的安全区（域）。算法的确定性保证了算法每次运行时具有相同输入数据和非常短的运行时间的解决方案的可重复性。该方法与另外两种算法（一种确定性算法和一种启发式算法）进行了比较。本文比较了100个不同复杂度的测试用例（在COLREGs中定义的简单遭遇战以及与多达20艘目标船的多船遭遇战）的结果。该算法以级联方式搜索解决方案，与维持较短运行时间的其他算法相比，可以实现竞争性结果。这些特性允许将这种避碰（COLAV）方法应用于自主船舶和无人水面船舶（usv）的商业系统中。

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引用次数: 0

Adaptive neural network fault-tolerant sliding mode control for ship berthing with actuator faults and input saturation 具有执行器故障和输入饱和的船舶靠泊自适应神经网络容错滑模控制

IF 2.3 3区工程技术 Q2 ENGINEERING, MARINE

International Journal of Naval Architecture and Ocean Engineering

Pub Date : 2025-01-01 DOI: 10.1016/j.ijnaoe.2025.100644

Son Tung Vu , Thai Duong Nguyen , Hai Van Dang , Van Suong Nguyen

This paper develops a robust controller for automatic ship berthing subjected to actuator faults, input saturation, modeling uncertainties, and external disturbances. First, sliding mode control (SMC) is used as a core controller to provide robust features for the ship berthing system. Second, fault-tolerant control (FTC) is combined with the controller to face the actuator faults. Third, the radial basis function (RBF) neural network is employed to approximate the modeling uncertainties while the effect of external disturbances is compensated by an adaptive control technique. In addition, an anti-saturation auxiliary system is conducted to deal with the input saturation for physical limitations of the actuators. Finally, numerical simulation and comparison of the results with the other control approaches are carried out to highlight the advantages of the proposed controller.

针对船舶自动靠泊系统中执行器故障、输入饱和、建模不确定性和外部干扰等问题，设计了一种鲁棒控制器。首先，采用滑模控制作为核心控制器，为船舶靠泊系统提供鲁棒性。其次，将容错控制（FTC）与控制器相结合，以应对执行器故障。第三，采用径向基函数（RBF）神经网络逼近建模不确定性，同时采用自适应控制技术补偿外部干扰的影响。此外，由于执行器的物理限制，设计了抗饱和辅助系统来处理输入饱和。最后进行了数值仿真，并与其他控制方法的结果进行了比较，以突出所提控制器的优点。

引用次数: 0

Horizontal plane course-stability and manoeuvres of a twin-screw surface combatant depending on appendage dimensions 依赖附件尺寸的双螺旋水面战斗舰的水平面航向稳定性和机动

IF 2.3 3区工程技术 Q2 ENGINEERING, MARINE

International Journal of Naval Architecture and Ocean Engineering

Pub Date : 2025-01-01 DOI: 10.1016/j.ijnaoe.2025.100655

Dong-Jin Kim, Haeseong Ahn, Dong Jin Yeo

In this study, powering and manoeuvring performance of a twin-screw surface combatant, ONR tumblehome (ONRT), are estimated through towing tank captive model tests, and influences of appendage dimensions on its course-stabilities and manoeuvres are investigated by system-based simulation techniques. At first, resistance and propulsion tests are carried out at Froude numbers up to 0.4 in the towing tank of Korea Research Institute of Ships and Ocean Engineering (KRISO) so that its full-scale powering performance can be considered in the present simulation model. In particular, the residuary resistance is significantly affected by patterns of hull generated waves. Secondly, horizontal planar motion mechanism (HPMM) tests are performed to derive hydrodynamic coefficients in surge, sway, and yaw directions. By using 3-DoF modular-type models, turn and zig-zag manoeuvres are simulated, and simulations are validated with existing benchmark free-run model tests. Sway-yaw coupled linear whole ship models are also established in order to assess a straight-line stability of a rudder-fixed ONRT whole ship. Linear hydrodynamic coefficients are decomposed into hull and appendage components so that influences of appendage dimensions on ship manoeuvres can be analyzed in more detail. When the rudder area is enlarged or reduced, the coefficient and the location of a centerline skeg are redesigned under the constraint straight-line stabilities are identical. For one original ONRT and two modified ships, turn and zig-zag manoeuvres are simulated by linear whole ship models. Even though straight-line stabilities are identical, the turning diameter is decreased while zig-zag overshoot angles are increased with increasing rudder area. To ensure sufficient manoeuvrabilities of such a twin-screw ship, careful attentions should be paid to design of a centerline skeg and rudders.

本文通过拖曳坦克自备模型试验，对双螺杆水面作战舰艇“滚落之家”（ONR tumblehome， ONRT）的动力性能和机动性能进行了评估，并采用系统仿真技术研究了附件尺寸对其航向稳定性和机动性能的影响。首先，在韩国船舶海洋工程研究院（KRISO）的拖曳舱中，在弗劳德数高达0.4的情况下进行阻力和推进试验，以便在本仿真模型中考虑其全尺寸动力性能。特别是，船体产生的波浪模式对剩余阻力有显著影响。其次，进行了水平平面运动机构（HPMM）试验，得到了浪涌、摇摆和偏航方向的水动力系数。采用三自由度模块化模型，仿真了转向和之字形机动，并与已有的基准自由运行模型试验进行了验证。为了评估定舵ONRT整船的直线稳定性，建立了横摆耦合线性全船模型。将线性水动力系数分解为船体和附属物两部分，以便更详细地分析附属物尺寸对船舶操纵性能的影响。当舵面积增大或减小时，在直线稳定性相同的约束条件下，重新设计了系数和中心线偏差的位置。针对一艘原舰和两艘改进型舰，采用线性全船模型对转弯和之字形操纵进行了仿真。尽管直线稳定性相同，但随着舵面积的增加，转弯直径减小，而之字形超调角增大。为了保证这种双螺杆船有足够的操纵性，在设计中线舵和舵时应特别注意。

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引用次数: 0