Ocean Engineering最新文献_第6页

Channel-aware demodulation techniques for chaotic non-coherent underwater acoustic communication 混沌非相干水声通信的信道感知解调技术

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-13 DOI: 10.1016/j.oceaneng.2026.124172

Wei Zhang , Yonglin Zhang , Lixin Wu , Jun Wang , Yupeng Tai , Longxu Wang , Xianpeng Li , Haibin Wang

In long-range underwater acoustic communication (LR-UWAC), the acoustic channel is highly complex, posing significant challenges to traditional demodulation techniques. This paper proposes two channel-aware demodulation techniques for chaotic non-coherent signals: channel-weighted demodulation (CWD) and narrowband-focused demodulation (NFD). CWD augments conventional quadrature demodulation (QD) by incorporating narrowband energy information of the frequency-domain channel into the decision metric, thereby mitigating the effects of frequency-selective fading. Building upon CWD, NFD introduces virtual time reversal mirror (VTRM) to suppress inter-symbol interference (ISI) caused by severe multipath delay spread in the channel. Extensive simulations across measured LR-UWAC channels show that, relative to conventional QD, CWD reduces average bit error rate (BER) by 32% and NFD by 80% under the tested conditions. NFD yields particularly large gains in channels with complex multipath structures, while CWD performs better at low SNR in simpler channels. Finally, we designed and conducted an experiment in the South China Sea. Processing of the experimental CMFSK signals validated the effectiveness of the two proposed methods.

在远程水声通信（LR-UWAC）中，声信道非常复杂，对传统的解调技术提出了重大挑战。提出了两种信道感知的混沌非相干信号解调技术：信道加权解调（CWD）和窄带聚焦解调（NFD）。CWD通过将频域信道的窄带能量信息纳入决策度量，增强了传统正交解调（QD），从而减轻了频率选择性衰落的影响。在CWD的基础上，NFD引入了虚拟时间反转镜像（VTRM）来抑制由信道中严重的多径延迟传播引起的码间干扰（ISI）。在测量的LR-UWAC信道上进行的大量模拟表明，在测试条件下，相对于传统的QD， CWD将平均误码率（BER）降低了32%，NFD降低了80%。在具有复杂多径结构的信道中，NFD的增益特别大，而CWD在更简单的信道中，在低信噪比下表现更好。最后，我们在南海设计并进行了实验。对实验CMFSK信号的处理验证了两种方法的有效性。

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引用次数: 0

Research on wave energy harvesting and dissipation for buoys based on Savonius rotors 基于Savonius转子的浮标波浪能收集与耗散研究

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-13 DOI: 10.1016/j.oceaneng.2026.124241

Ruiyin Song , Congjie Ren , Haihan Yu , Xi Cui , Fengshen Li , Boyu Liu , Kai Chen , Dongming Hu , Wei Li

Compared to traditional deep-sea cages, ship-type net cages offer advantages such as self-adjusting orientation and reduced wave-facing area. However, they still face challenges like the need to enhance wave attenuation and flow reduction capabilities at the bow section and difficulties in meeting power demands. The Savonius rotor (S-rotor) shows application potential in marine energy utilization due to its simple structure and good self-starting performance. This paper proposes integrating the S-rotor with the net cage pontoon framework to enhance the wave resistance and power generation capacity. Three configurations of S-rotor dual-pontoon integrated mechanisms are proposed: external rotor, embedded rotor, and hybrid distributed rotor. Through combined numerical simulation and physical experiments, a comparative analysis of the coupled hydrodynamic performance of these integrated mechanisms was conducted, revealing that the hybrid distributed configuration shows significant advantages in comprehensive wave energy utilization. Furthermore, the Analytic Hierarchy Process (AHP) was innovatively introduced to establish a four-dimensional decision-making model. A dynamic decision system was constructed with wave attenuation performance and power generation efficiency as core indicators, confirming that the hybrid configuration stably leads in comprehensive score within a weight fluctuation range of ±20 %, providing a generalizable methodological tool for multi-objective optimization of marine composite structures.

与传统的深海网箱相比，船型网箱具有自调整方向和减小迎波面积等优点。然而，他们仍然面临着诸如需要增强艏段的波衰减和减流能力以及满足功率需求的困难等挑战。萨沃纽斯转子（s -转子）结构简单，自启动性能好，在海洋能源利用中具有应用潜力。本文提出将s型转子与网箱式浮桥框架相结合，提高浮桥的抗波能力和发电能力。提出了s转子双浮筒集成机构的三种构型：外置转子、内嵌转子和混合式分布式转子。通过数值模拟与物理实验相结合的方法，对这些综合机构的耦合水动力性能进行了对比分析，发现混合分布构型在波浪能综合利用方面具有显著优势。在此基础上，创新性地引入层次分析法（AHP），建立了四维决策模型。构建了以消波性能和发电效率为核心指标的动态决策系统，在权重波动±20%的范围内，混合构型综合得分稳定领先，为海洋复合材料结构多目标优化提供了可推广的方法工具。

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引用次数: 0

A scoring-based approach for monitoring high-pressure ammonia leaks in marine engine rooms 船舶机舱高压氨泄漏的计分监测方法

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-13 DOI: 10.1016/j.oceaneng.2026.124188

Yu Fan , Yuxuan Luo , Liangtao Xie , Zerong Xie , Haonan Wang , Jianguo Yang

Ammonia leakage from high-pressure supply pipelines in marine ammonia-fueled engines presents a major safety challenge for the shipping industry. This study establishes a reliable computational fluid dynamics model through laboratory-scale ammonia leakage experiments, with simulation errors maintained below 10 %. The validated model was applied to analyze high-pressure liquid ammonia leakage dispersion in a full-scale marine engine compartment. The main contribution lies in developing an innovative scoring methodology for sensor placement optimization, which systematically evaluates different vertical zones based on average concentration, distribution intensity, and peak concentration. Analysis reveals three critical monitoring regions: the leakage source at the bottom, the 12–20 m height level, and the compartment top, corresponding to plume development and accumulation areas. Implementation of this scoring method under ventilated conditions demonstrates a 17.6 % reduction in average concentration intensity and a 14.9 % decrease in comprehensive risk score compared to non-ventilated scenarios. The proposed scoring framework provides a scientifically grounded and practical approach for designing effective ammonia leakage monitoring systems, supporting enhanced safety management in ammonia-fueled vessels through optimized early detection capabilities.

船用氨燃料发动机高压供氨管道泄漏是航运业面临的一个重大安全挑战。本研究通过实验室规模的氨泄漏实验，建立了可靠的计算流体动力学模型，仿真误差保持在10%以下。将该模型应用于某全尺寸船舶发动机舱高压液氨泄漏扩散分析。主要贡献在于开发了一种创新的传感器布局优化评分方法，该方法基于平均浓度、分布强度和峰值浓度系统地评估不同的垂直区域。分析发现底部泄漏源、12 ~ 20 m高度和隔室顶部为3个关键监测区域，对应烟柱发育和聚集区域。在通风条件下实施这种评分方法表明，与不通风的情况相比，平均浓度强度降低了17.6%，综合风险评分降低了14.9%。提出的评分框架为设计有效的氨泄漏监测系统提供了科学依据和实用方法，通过优化早期检测能力，支持加强氨燃料容器的安全管理。

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引用次数: 0

Modeling, control, and performance analysis of a wall-mounted oscillating-body wave energy converter for tower structures 塔式壁挂式振体波能量转换器的建模、控制与性能分析

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-13 DOI: 10.1016/j.oceaneng.2026.124251

Jialong Li, Wenbin Lai, Mingze Ji, Hongkun Yang, Muyu Zhao, Zhongzhi Yang, Shuanghong Zhou, Xiongbo Zheng

Integrating wave energy converters (WECs) with existing marine structures can significantly reduce construction costs and enhance power generation efficiency. This paper proposes a wall-mounted oscillating-body WEC designed for towers of offshore wind turbines or offshore platforms. First, a time-domain dynamic model of the WEC is developed using AQWA and STAR-CCM+, with the fluid viscous effects quantitatively characterized. Subsequently, a model predictive control (MPC) framework for the WEC is established, incorporating a Fast Fourier Transform (FFT)-based wave excitation force prediction model with endpoint constraints. The results indicate that the tower effect enhances wave excitation forces in 3–10 s periods, but increases fluid viscous effects as well. CFD results show the WEC viscous coefficients with and without the tower are 1.2 and 0.5, respectively. Under long-period wave conditions, the performance of MPC based on the FFT prediction model significantly outperforms the autoregressive (AR) prediction model. Finally, the performance of the Tower-WEC integrated system is analyzed under different layout orientations. The results indicate that the annual average power output is insensitive to the orientation, but the quarterly power generation is significantly affected by the orientation. Meanwhile, the installation of WEC can reduce wave loads on the tower structure but increases wave impact near the waterline.

将波浪能转换器（WECs）与现有海洋结构集成，可以显著降低建造成本，提高发电效率。本文提出了一种用于海上风力发电机组或海上平台塔架的壁挂式摆动体WEC。首先，利用AQWA和STAR-CCM+建立了WEC的时域动力学模型，定量表征了流体粘性效应；随后，建立了WEC的模型预测控制（MPC）框架，该框架结合了基于快速傅里叶变换（FFT）的具有端点约束的波浪激励力预测模型。结果表明，塔效应在3 ~ 10 s周期内增强了波浪激振力，但也增强了流体粘性效应。CFD计算结果表明，带塔和不带塔的WEC粘性系数分别为1.2和0.5。在长周期波动条件下，基于FFT预测模型的MPC的性能明显优于自回归（AR）预测模型。最后，分析了不同布局方向下塔- wec集成系统的性能。结果表明，年平均发电量对风向不敏感，而季度发电量受风向影响显著。同时，WEC的安装减少了塔结构的波浪荷载，但增加了水线附近的波浪冲击。

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引用次数: 0

Airborne sound power levels and third octave band spectra of passenger ships across operational phases in the Port of Split 斯普利特港各运营阶段客船的机载声功率级和第三倍频带频谱

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-13 DOI: 10.1016/j.oceaneng.2026.124291

Luca Fredianelli , Marco Bernardini , Domenico Profumo , Luka Vukic

Mapping airborne environmental noise in passenger ports is increasingly important due to their proximity to residential areas and associated health risks. Predictive models have been limited by the scarcity of reliable airborne sound power data for ships under real operating conditions. This study addresses that gap through a short-term campaign at the Port of Split (Croatia). A-weighted sound power levels and third-octave spectra were derived for ferries, cruise ships, and catamarans during key operational phases: hotelling (at berth), loading/unloading, arrival, and departure. Measurements were conducted by qualified personnel with Class-1 instrumentation under favorable meteorological conditions and processed following established procedures. Results show marked differences among ship types and phases. Small catamarans are generally quiet except for auxiliary ventilation near departure; large catamarans exhibit higher levels at departure due to engine activation. Ferries separate into two behaviors: large units emit continuously during hotelling from ventilation and auxiliary machinery, whereas small ferries can be silent at berth or operate low-mounted engines intermittently. Cruise ships produced significant airborne noise mainly during hotelling, with elevated source heights that may enhance propagation toward urban receivers. The resulting dataset, based on repeated operations in a regular port schedule, offers directly model-ready inputs for noise mapping.

由于客运港靠近居民区并存在相关的健康风险，因此绘制客运港空气环境噪声地图变得越来越重要。由于舰船在实际操作条件下缺乏可靠的机载声功率数据，预测模型一直受到限制。本研究通过在斯普利特港（克罗地亚）开展的短期活动解决了这一差距。a加权声功率级和三倍频谱在渡轮，游轮和双体船的关键操作阶段：住宿（泊位），装卸，到达和离开。测量由合格人员使用一级仪器在有利的气象条件下进行，并按照既定程序进行处理。结果表明，不同船型和船相间存在显著差异。小型双体船通常是安静的，除了离港附近的辅助通风；大型双体船在出发时由于发动机激活而表现出更高的水平。轮渡分为两种行为：大型轮渡在入住期间通过通风和辅助机械持续排放，而小型轮渡在泊位时可以静音或间歇性地运行低安装的发动机。邮轮主要在酒店入住期间产生显著的空气噪声，噪声源高度升高可能会增强向城市接收器的传播。由此产生的数据集基于常规港口计划中的重复操作，为噪声映射提供了直接的模型就绪输入。

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引用次数: 0

Cavity regime and jet impacting form during water entry of axisymmetric body with T-shaped annularly distributed flow diversion orifices 带t形环形导流孔轴对称体进水时的空腔形态和射流冲击形式

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-12 DOI: 10.1016/j.oceaneng.2026.124293

Le Shen, Bowen Zhao, Hancheng Zhang, Gaoke Ji, Ying Chen

Water entry of a traditional axisymmetric body usually generates a smooth cavity with a regular shape, but not necessarily if a specific impact mitigation method is used. The present work explores the water entry of a transparent resin axisymmetric body with T-shaped annularly distributed flow diversion orifices, which were shown to have impact mitigation effect in our previous work. Water can be guided from the front stagnation point of the body to flow through the orifices and produce radial jets. In this study, the cavity regime, jet features, and flow structure are investigated using experimental models with different orifice diameters and axial positions, which yield distinct mixing effects when the jet flows out. There are two types of cavity regime: smooth cavity and chaotic cavity, as well as three types of water jet impact form: impacting surrounding water, impacting cavity wall, and transition between them. The jet from the radial orifices at the lower position violently interacts with the cavity wall and changes the cavity shape, whereas the jet from the orifices at higher positions interacts with the surrounding water behind the cavity closure to produce bubble clusters that move toward the free water surface. The Froude number and orifice diameter do not affect the jet impact form at the lower position but influence those at the middle and upper positions. When the Froude number is adequately large, the cavity and jet of the middle orifice stabilize if the orifice diameter expands, whereas the opposite occurs for the upper orifices.

传统轴对称体入水后通常会形成形状规则的光滑空腔，但如果采用特定的减冲方法则不一定。本研究探讨了透明树脂轴对称体的水进入，该体具有t形环形分布导流孔，在我们之前的工作中已经证明了它具有减缓冲击的效果。水可以被引导从阀体的前端滞止点流过孔口并产生径向射流。在本研究中，使用不同孔径和轴向位置的实验模型，研究了射流流出时产生不同混合效应的空腔形态、射流特征和流动结构。存在光滑空腔和混沌空腔两种型态，以及三种水射流冲击形式：冲击周围水、冲击空腔壁和两者之间的过渡。来自较低位置径向孔的射流猛烈地与空腔壁相互作用，改变了空腔的形状，而来自较高位置孔的射流与空腔闭合后周围的水相互作用，产生气泡团，并向自由水面移动。弗劳德数和孔口直径对下部射流的冲击形式没有影响，但对中部和上部射流的冲击形式有影响。当弗劳德数足够大时，随着孔直径的扩大，中孔的空腔和射流趋于稳定，而上孔的空腔和射流则相反。

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引用次数: 0

Study of parameters for excessive acceleration failure mode in design stage 设计阶段超加速失效模式参数研究

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-12 DOI: 10.1016/j.oceaneng.2026.124250

Takako Kuroda

The excessive acceleration failure mode is one of the five stability failure modes outlined in the interim guidelines on the second generation intact stability criteria approved by the International Maritime Organization. This failure mode differs from others because vessels with large metacentric heights may be highly vulnerable. Previous studies have reported that many existing vessels do not comply with vulnerability assessments for this failure mode. Therefore, measures against excessive acceleration failure modes must be considered or the criteria are too strict. In this study, the sensitivity of calculation parameters other than hull form included in the vulnerability assessment was investigated. Based on the results, it is proposed that an effective measure against this failure mode in the design stage is to specify the height of the assessment location that complies with the vulnerability assessment, and the decks above the specified height should be equipped with safety devices such as harnesses and handrails.

过度加速失效模式是国际海事组织批准的第二代完整稳定性标准临时指南中概述的五种稳定性失效模式之一。这种失效模式与其他失效模式不同，因为具有较大稳心高度的血管可能非常脆弱。先前的研究报告称，许多现有的船舶不符合这种失效模式的脆弱性评估。因此，必须考虑防止过度加速失效模式的措施或标准过于严格。本研究对船体易损性评估中除船体形状外的计算参数的敏感性进行了研究。根据研究结果，提出在设计阶段针对这种破坏模式的有效措施是规定符合易损性评估的评价位置高度，并在规定高度以上的甲板上设置吊带、扶手等安全装置。

引用次数: 0

Dynamic frame rate recognition for vision-based deployment and recovery of USVs 基于视觉的无人潜航器部署和恢复的动态帧率识别

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-12 DOI: 10.1016/j.oceaneng.2025.124148

Shengxuan Meng , Minlong Fu , Changbin Wang , Xiaonan Li , Dalei Song , Qianli Jiang

Gimbal-assisted deployment and recovery of crane-launched unmanned surface vehicles (USVs) is emerging as a critical enabler of intelligent maritime operations. During recovery, a visual gimbal system mounted on the mothership is responsible for tracking and docking with the returning USV. However, despite the strong computational power of the NVIDIA Jetson series AI development boards, computational resources are still limited when performing multiple image processing tasks simultaneously under adverse environmental conditions. To overcome this limitation, we present a ”multi-scenario” dataset tailored to dynamic maritime environments and introduce DyFPS, a dynamic frame rate adaptation algorithm that adjusts recognition frequency in real time based on USV velocity, weather variability, and day-night transitions. Integrated into a custom-built gimbal platform, DyFPS dynamically optimizes recognition frame rates and significantly reduces GPU utilization, ensuring robust tracking performance. This lightweight, adaptive approach enables more robust and energy-efficient visual perception, offering a scalable solution for intelligent USV operations in complex open-water environments. The dataset is publicly available and can be accessed through the following link: https://github.com/lqs-07/Multi-scenario-datasets?tab=readme-ov-file.

起重机发射的无人水面车辆（usv）的平衡架辅助部署和回收正在成为智能海上作战的关键推动因素。在恢复期间，安装在母舰上的视觉万向系统负责跟踪并与返回的USV对接。然而，尽管NVIDIA Jetson系列AI开发板具有强大的计算能力，但在恶劣环境条件下同时执行多个图像处理任务时，计算资源仍然有限。为了克服这一限制，我们提出了一个针对动态海洋环境量身定制的“多场景”数据集，并引入了DyFPS，这是一种动态帧率自适应算法，可根据USV速度、天气变化和昼夜转换实时调整识别频率。DyFPS集成到定制的万向架平台中，动态优化识别帧率，显著降低GPU利用率，确保稳健的跟踪性能。这种轻量级、自适应的方法实现了更强大、更节能的视觉感知，为复杂开放水域环境中的智能USV操作提供了可扩展的解决方案。该数据集是公开的，可以通过以下链接访问：https://github.com/lqs-07/Multi-scenario-datasets?tab=readme-ov-file。

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引用次数: 0

Investigation of wet-towing of elevated railway floating bridge in inland rivers considering shallow water wave: A case study of the Yangtze River 考虑浅水波的内河高架铁路浮桥湿拖研究——以长江为例

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-12 DOI: 10.1016/j.oceaneng.2026.124259

Yaxuan Yang , Cunbao Zhao , Nanpeng Li , Chana Sinsabvarodom

This study investigates the wet-towing dynamics of an Elevated Railway Floating Bridge (ERFB) designed for emergency repair operations in inland waterways. A coupled numerical model was developed using SESAM and MATLAB co-simulation to analyze the ERFB responses under combined wave and current loading, with validation performed against established benchmarks. Based on measured hydrological conditions from the Yangtze River, the research examines shallow-water wave attenuation effects and the influence of current magnitude and direction on towing safety. Results demonstrate that shallow-water effects significantly alter motion predictions. At 9 m water depth, the TMA spectrum yields maximum heave and pitch motions 25 % and 31 % lower than the JONSWAP spectrum, respectively, confirming substantial wave energy attenuation in depth-limited conditions. Despite increased wave energy dissipation at longer periods, structural resonance remains the dominant factor governing motion response. Current analysis reveals that velocity and direction collectively influence system dynamics and cable tension through modifications to encounter frequency and damping characteristics. Critically, down-current conditions at low to medium velocities are identified as producing the largest response, representing the most hazardous operational scenario. The findings provide quantitative design criteria for safe towing operations of inland floating structures in shallow-water environments.

本研究探讨了内河航道紧急抢修高架铁路浮桥（ERFB）的湿拖动力学。利用SESAM和MATLAB联合仿真建立了耦合数值模型，分析了波浪和电流联合载荷下的ERFB响应，并根据既定基准进行了验证。以长江实测水文条件为基础，研究了浅水波的衰减效应以及水流大小和方向对拖带安全的影响。结果表明，浅水效应显著改变运动预测。在9米水深处，TMA频谱产生的最大起伏和俯仰运动分别比JONSWAP频谱低25%和31%，这证实了在深度有限的条件下波浪能量的大量衰减。尽管长周期波能耗散增加，但结构共振仍然是控制运动响应的主要因素。目前的分析表明，速度和方向通过改变遇到的频率和阻尼特性，共同影响系统动力学和索张力。关键的是，低至中等流速的下电流条件被确定为产生最大的响应，代表了最危险的操作场景。研究结果为浅水环境下内陆浮式结构物的安全拖曳作业提供了定量设计准则。

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引用次数: 0

Hydrodynamic loads and motion responses of a conical platform moored in an ice polynya using a hybrid method 用混合方法研究冰冰多冰槽中锥形平台的水动力载荷和运动响应

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-01-12 DOI: 10.1016/j.oceaneng.2026.124205

Z.F. Li , J.Y. Ma , Y.Y. Shi , X.W. Tong

Moored floating platforms are widely used in the Arctic region to meet the demands of oil and gas extraction. It is crucial to accurately simulate the interaction between these platforms and wave loads in ice environments. A hybrid method is utilized to numerically simulate the motion responses and hydrodynamic forces of a moored floating platform in an ice polynya.Linear velocity potential theory is utilized to model fluid flow, and elastic plate theory is applied to the ice sheet of infinite extent.In the ice polynya, a boundary integral equation (BIE) is established around the floating platform; in the external ice-covered area, the velocity potential is expanded vertically into a series of eigenfunctions. Combined with the integral equation at the edge of the ice sheet, the continuity conditions for normal velocity and pressure are applied at the interface to solve the coefficients of the BIE and eigenfunction expansion together. The hydrodynamic forces obtained from the solution are substituted into the motion equation of the mooring system to calculate the motion responses. Numerical simulations are presented in detail, focusing on the influence of ice thickness, polynya size, and the offset position of the floating platform.

系泊式浮式平台在北极地区广泛应用，以满足石油和天然气开采的需求。准确模拟这些平台与冰环境中波浪荷载之间的相互作用是至关重要的。采用一种混合方法，对冰冰堆中系泊浮式平台的运动响应和水动力进行了数值模拟。用线速度势理论模拟流体流动，用弹性板理论模拟无限范围的冰盖。在冰堆中，围绕浮平台建立边界积分方程（BIE）；在外冰覆盖区域，速度势在垂直方向上展开为一系列特征函数。结合冰盖边缘的积分方程，在界面处应用法向速度和压力的连续性条件，共同求解BIE系数和特征函数展开。将求解得到的水动力代入系泊系统的运动方程，计算系泊系统的运动响应。详细地进行了数值模拟，重点研究了冰厚、冰槽大小和浮平台偏移位置对冰槽漂移的影响。

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引用次数: 0