Ocean Engineering最新文献_第10页

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 : 2026-04-15 Epub 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

The impact of onshore wind on regular wave overtopping at Accropode-armoured seawall 陆上风对accropod铠装海堤规则浪涌的影响

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-04-15 Epub Date: 2026-02-09 DOI: 10.1016/j.oceaneng.2026.124546

Yuerui Jin , Junning Pan , Biyao Zhai , Fan Yang , Zhaojun Wang , Yue Zhao

Although wave overtopping at seawalls has been extensively studied, the influence of wind on wave overtopping discharge remains insufficiently quantified. This study explores the influence of wind on seawall overtopping behaviour by combining physical experiments with numerical simulations. A wind-wave coupled numerical model based on olaFlow is developed, and the results of the numerical simulations are validated through physical experiments to ensure the reliability of the model. The results show that wave overtopping discharge and overtopping layer thickness decrease with increasing relative freeboard and increase with rising wind speed, with the wind effect being most pronounced under conditions of large relative freeboard and high wave steepness. Based on the above findings, this study proposes an empirical correction formula to quantify the effects of onshore wind on wave overtopping discharge, thereby effectively improving the accuracy of overtopping prediction and its practical applicability in coastal engineering.

虽然对海堤的波浪过顶进行了广泛的研究，但风对波浪过顶流量的影响仍然不够量化。本文采用物理实验与数值模拟相结合的方法，探讨了风对海堤过顶行为的影响。建立了基于olaFlow的风浪耦合数值模型，并通过物理实验对数值模拟结果进行了验证，保证了模型的可靠性。结果表明：波浪过顶流量和过顶层厚度随相对干舷增大而减小，随风速增大而增大，其中相对干舷大、波浪陡度大时风效应最为明显；基于以上发现，本研究提出了一种经验修正公式来量化陆上风对波浪过顶流量的影响，从而有效地提高了过顶预测的精度及其在海岸工程中的实用性。

引用次数: 0

Dynamic response of trawl otter board based on computational fluid dynamics 基于计算流体力学的拖网水獭板动力响应

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-04-15 Epub Date: 2026-02-06 DOI: 10.1016/j.oceaneng.2026.124308

Cheng Zhao , Xiaobin Li , Yonghe Xie , Guoqiang Li , Wei Wang

To analyze the dynamics of otter boards, a coupled three-dimensional hydrodynamic model for trawl systems is formulated. The model solves the hydrodynamic forces on the otter boards via computational fluid dynamics, represents warps using the lumped mass method, and couples the force interactions among the warps, otter boards, and trawl nets. The six degrees of freedom of the otter board are calculated under varying flow velocities and warp lengths. The position and attitude of the otter board are compared in a stable state, whereas the morphology and tension changes of the warp under different operating conditions are analyzed. The numerical calculation results are compared with sea trial results to verify the reliability of the model. The results indicate that the method enhances the accuracy of otter board motion calculations in trawl systems and provides a useful tool for achieving appropriate control of midwater trawl gears under different operating conditions.

为了分析水獭板的动力学特性，建立了拖网系统三维水动力耦合模型。该模型采用计算流体力学方法求解水獭板上的水动力，采用集总质量法表示翘曲，并将翘曲、水獭板和拖网之间的力相互作用耦合起来。计算了水獭板在不同流速和经纱长度下的六个自由度。比较了水獭板在稳定状态下的位置和姿态，分析了不同工况下经纱的形态和张力变化。将数值计算结果与海试结果进行了比较，验证了模型的可靠性。结果表明，该方法提高了拖网系统中水獭板运动计算的精度，为实现不同工况下中水拖网齿轮的合理控制提供了有益的工具。

引用次数: 0

Experimental study of wave-induced seabed response around a jacket structure with different arrangements 不同布置夹套结构周围海底波致响应试验研究

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-04-15 Epub Date: 2026-02-06 DOI: 10.1016/j.oceaneng.2026.124512

Chenglin Liu , Titi Sui , Hao Chen , Jisheng Zhang

The seabed response and instability induced by transient liquefaction are of great concern to coastal engineers and researchers, which could threaten the safety of offshore structures, such as wind turbine foundations. Recently, the jacket has become the most commonly used offshore pile foundation due to its larger carrying capacity and risk resistance performance. In this study, an experimental investigation of the wave-induced seabed response around a jacket foundation was conducted in a water flume. A total of 14 series of experiments were conducted to analyze the pore pressure variation with different loading conditions. Meanwhile, the influence of wave conditions and structure arrangements on the pore pressure distribution was also analyzed. Experimental results show that, (1) the pore pressure shows different distribution at piles’ upstream and downstream sides, the difference at the both ends of the jacket is obvious but slight at the two lateral piles; (2) the pore pressure amplitude increases with the angle between the structure’s symmetry axis and the flow direction, and the pore pressure inside the jacket is greater than that at the outer ends; (3) the asymmetrical arrangement of the jacket increases the liquefaction potential (I_L) around the structure.

瞬态液化引起的海底响应和失稳是海岸工程和研究人员非常关注的问题，它可能威胁到海上结构的安全，如风力发电机基础。近年来，导管套以其更大的承载能力和抗风险性能成为最常用的海上桩基。在水槽中，对导管基础周围波浪海床响应进行了试验研究。共进行了14组试验，分析了不同加载条件下孔隙压力的变化规律。同时，分析了波浪条件和结构布置对孔隙压力分布的影响。试验结果表明，(1)桩的孔压力在桩的上下游两侧分布不同，在桩的两端导管处差异明显，而在桩的两侧导管处差异不大；(2)孔压幅值随结构对称轴与流动方向夹角增大而增大，夹套内孔压大于外端孔压；(3)夹套的不对称布置增加了结构周围的液化势（IL）。

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引用次数: 0

Data-driven optimization of Darrieus wind turbine pairs under particle-laden atmospheric conditions using LES and machine learning 基于LES和机器学习的大气粒子负载条件下Darrieus风力机对数据驱动优化

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-04-15 Epub Date: 2026-02-04 DOI: 10.1016/j.oceaneng.2026.124511

Esmaeel Fatahian, Rakesh Mishra, Hossein Fatahian, Leigh Fleming, Frankie F. Jackson

This study develops a hybrid machine-learning framework that couples CFD and artificial neural networks to quantify and optimize the performance of paired Darrieus turbines in clean-air and particle-laden environments. Targeting arid, semi-arid, and coastal sites where airborne sand accelerates blade degradation, the framework resolves the influence of sand-induced surface roughness on turbine aerodynamics and power output. Clean-air CFD results are used to determine baseline optimal design parameters, which are subsequently tested under sand-particle conditions (0.5–2 mm) using LES to evaluate aerodynamic losses and erosion. A Single-Objective Genetic Algorithm (SOGA) identifies the turbine configuration that maximizes the average power coefficient (C_P). Results show that larger sand particles significantly reduce performance, with a 4.8% decrease in C_P at a tip speed ratio of 2.24. Regression analysis reveals a strong correlation between particle size and blade erosion rate. The results show that leading-edge erosion reduces the pressure difference across the blade, slightly increases suction-side pressure at θ = 0°, weakens the suction peak at θ = 75°, and decreases flow attachment at θ = 150°. Lift is significantly lowered in the upwind region, while delayed flow reattachment and weaker lift recovery occur in the downwind region. Cumulative erosion analysis indicates that blades exposed to 0.5 mm particles exceed the 2 mm erosion limit in under two years, while exposure to 2 mm particles leads to critical wear within months, far below the 15-year design life.

本研究开发了一种混合机器学习框架，将CFD和人工神经网络结合起来，量化和优化配对Darrieus涡轮机在清洁空气和充满颗粒的环境中的性能。该框架以干旱、半干旱和沿海地区为目标，在这些地区，风沙加速了叶片的退化，解决了风沙引起的表面粗糙度对涡轮空气动力学和功率输出的影响。清洁空气CFD结果用于确定基线优化设计参数，随后使用LES在沙粒条件下（0.5-2 mm）进行测试，以评估气动损失和侵蚀。单目标遗传算法（SOGA）确定了最大平均功率系数（CP）的涡轮配置。结果表明，较大的砂粒显著降低了性能，在尖端速比为2.24时，CP降低了4.8%。回归分析表明，颗粒大小与叶片侵蚀速率之间存在很强的相关性。结果表明：前缘侵蚀减小了叶片间的压差，在θ = 0°处吸力侧压力略有增加，在θ = 75°处吸力峰减弱，在θ = 150°处流动依附减小；在逆风区域，升力明显降低，而在下风区域，流动再附着延迟，升力恢复较弱。累积侵蚀分析表明，暴露在0.5 mm颗粒中的叶片在不到两年的时间内就超过了2mm的侵蚀极限，而暴露在2mm颗粒中的叶片在几个月内就会出现临界磨损，远远低于15年的设计寿命。

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引用次数: 0

Bi-level multi-objective optimization of configuration and scheduling of offshore wind-solar-storage hybrid power system considering demand response 考虑需求响应的海上风电-太阳能-储能混合动力系统配置与调度的双层多目标优化

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-04-15 Epub Date: 2026-02-12 DOI: 10.1016/j.oceaneng.2026.124614

Meng Shao , Yutong Han , Jinwei Sun , Hao Xu , Xiangqi Kong , Huimin Wang , Bingjie Wang , Zhuxiao Shao , Jian Guan , Zezhi Qu

Due to the fluctuation and intermittency of offshore wind and solar power generation, offshore wind-solar-storage hybrid power system (OWSS-HPS) has emerged as a significant field for promoting energy transformation and addressing climate change. For ensuring the economic benefits and reliability of the OWSS-HPS over the entire life cycle, it necessitates a scientific and reasonable capacity planning configuration optimization which takes consideration of the practical operation scheduling. This paper proposes a novel bi-level multi-objective optimization model that couples the capacity configuration and operation scheduling based on the demand response (DR). An improved Non-dominated Sorting Genetic Algorithm II (NSGA-II) with an enhanced elite selection strategy is introduced to generate the Pareto front, and the TOPSIS method is applied to determine the final optimal solution. A coastal industrial area in the South China Sea serves as the case study. The results show that under the DR mechanism with 30% participation, the system achieves optimal performance, comprising 497.31 MW of offshore wind turbines, 488.65 MW of offshore photovoltaics, and 397.67 MW of battery energy storage systems. Under this setup, the LCOE is 0.5581 CNY/kWh, and the LPSP is 1.90%. This study provides theoretical support for the construction of practical OWSS-HPS.

由于海上风电和太阳能发电的波动性和间歇性，海上风能-太阳能-储能混合发电系统（OWSS-HPS）已成为促进能源转型和应对气候变化的重要领域。为保证OWSS-HPS全生命周期的经济效益和可靠性，需要在考虑实际运行调度的基础上进行科学合理的容量规划配置优化。提出了一种基于需求响应的容量配置与运行调度耦合的双层多目标优化模型。引入改进的非支配排序遗传算法II （NSGA-II）和增强的精英选择策略来生成Pareto前沿，并采用TOPSIS方法确定最终最优解。南中国海的一个沿海工业区作为案例研究。结果表明，在30%参与率的DR机制下，系统性能最优，包括497.31 MW海上风电、488.65 MW海上光伏和397.67 MW电池储能系统。在此设置下，LCOE为0.5581元/千瓦时，LPSP为1.90%。本研究为构建实用的OWSS-HPS提供了理论支持。

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引用次数: 0

Oblique wave interaction with (M+1) U-shaped thick porous structures interconnected with (M) thin porous boxes in the presence of dual trenches near a partially reflected wall 斜波与（M+1）个u形厚多孔结构相互作用，与(M)个薄多孔盒子相互连接，存在于部分反射壁附近的双沟槽中

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-04-15 Epub Date: 2026-02-11 DOI: 10.1016/j.oceaneng.2026.124505

P Jothika, R Gayathri, M Chandru

This study presents a comprehensive investigation into the hydrodynamic behavior of a hybrid coastal structure consisting of an interconnected thick and thin porous configuration, with a partially reflective vertical wall and an array of periodic trenches. The system is subjected to oblique wave incidence, and the corresponding boundary value problem is addressed through a multi-domain boundary element framework. Numerical simulations are conducted to evaluate wave scattering characteristics, including reflection coefficients, hydrodynamic forces on the seaside thin porous box and U-shaped structure, and the moment on the floating box. The results found that the wave run-up, wave forces, and moment on the porous box reduce as the interconnected structures increase. The study reveals that the radius, thick porosity, and porous effect parameter attenuate the wave reflection. In addition, the effect of U-shaped structures plays a major role in mitigating the forces and moment on the porous box. These insights offer valuable guidance for the engineering of multifunctional coastal systems, including harbor tranquility zones, sediment transport, aquaculture shielding frameworks, and modular floating breakwaters.

本研究对一个混合海岸结构的水动力行为进行了全面的研究，该结构由一个相互连接的厚和薄多孔结构组成，具有部分反射的垂直壁和一系列周期性沟槽。系统受到斜入射波的作用，通过多域边界元框架解决了相应的边值问题。数值模拟计算了波浪散射特性，包括反射系数、海边薄多孔箱和u型结构的水动力以及浮箱上的力矩。结果表明，随着结构的增加，孔箱上的波浪爬高、波浪力和弯矩减小。研究表明，半径、厚孔隙度和多孔效应参数对波反射有衰减作用。此外，u型结构对多孔箱的受力和弯矩的减小起着重要的作用。这些见解为多功能海岸系统的工程设计提供了有价值的指导，包括港口宁静区、沉积物运输、水产养殖屏蔽框架和模块化浮动防波堤。

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引用次数: 0

Experimental study of clear-water local scour around a large-diameter monopile in silty sand 粉质砂中大直径单桩周围清水局部冲刷试验研究

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-04-15 Epub Date: 2026-02-11 DOI: 10.1016/j.oceaneng.2026.124463

Dong Wang , Sheng Yan , Shaowu Li

This study experimentally investigates clear-water scour around a large-diameter monopile (0.60 m) in silty sand, featuring an exceptionally high pile-to-sediment size ratio (7500). The large diameter and non-uniform silty sand jointly produce distinct scour behaviors, including prolonged equilibrium times (6–10 days), formation of a coarse-grained armor layer at the scour base, and shallower equilibrium depths compared to non-cohesive sands. The effects of approach velocity and flow shallowness on scour evolution were systematically examined. Real-time internal imaging and total-station surveys captured the temporal development and three-dimensional geometry of the scour hole. Scour progressed through three stages—rapid initiation, progressive deepening, and asymptotic equilibrium—with bed armoring limiting further erosion. Increased approach velocity deepened the scour and shortened the equilibrium time, while deeper flow reduced equilibrium depth and time under identical boundary-layer velocities. The results reveal the inadequacy of conventional predictors derived from small-scale sand-bed tests and highlight the need to incorporate partial-depth boundary-layer development, pile-to-sediment size ratio, and armoring effects in scour design for estuarine and nearshore foundations.

本研究通过实验研究了粉质砂中大直径单桩（0.60 m）周围的清水冲刷，该单桩具有极高的桩-沉积物尺寸比（7500）。大直径和不均匀粉砂共同产生了不同的冲刷行为，包括平衡时间延长（6-10天），冲刷底部形成粗粒装甲层，与非粘性砂相比，平衡深度较浅。系统考察了接近速度和水流浅度对冲刷演化的影响。实时内部成像和全站测量捕获了冲刷孔的时间发展和三维几何形状。冲刷通过三个阶段进行——快速启动、逐渐加深和渐近平衡——床层盔甲限制了进一步的侵蚀。当接近速度增加时，冲刷加深，平衡时间缩短，而在相同边界层速度下，较深的流动使平衡深度和平衡时间缩短。研究结果揭示了基于小规模沙床试验的传统预测方法的不足，并强调了在河口和近岸基础冲刷设计中考虑部分深度边界层发育、桩沙尺寸比和装甲效应的必要性。

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引用次数: 0

VIV model updating method of the flexible riser based on particle swarm optimization 基于粒子群优化的柔性立管涡激振动模型更新方法

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-04-15 Epub Date: 2026-02-06 DOI: 10.1016/j.oceaneng.2026.124516

Pengji Hu , Xiuquan Liu , Hongkun Gao , Ronggen Zhao , Xiaoyu Hu , Yuanjiang Chang , Guoming Chen , Wentuo Li , Mingyuan Sun

Vortex-induced vibration (VIV) of a riser is inevitably influenced by various uncertainties in environmental and structural parameters, leading to significant deviations between predicted and actual responses. This study proposes a novel VIV model updating method of the riser to enhance dynamic response prediction accuracy. A three-dimensional VIV analysis model is established based on the Euler-Bernoulli beam theory, with hydrodynamic loads calculated using a Van der Pol wake oscillator. The key parameters are identified by Morris global sensitivity analysis, and a model updating procedure is then developed using these parameters and particle swarm optimization (PSO) algorithm. The proposed method is validated through VIV experiments, and the model adaptive updating characteristics under both single and multiple flow conditions are further investigated. The results demonstrate that the VIV models updated separately for each single condition achieve significantly improved prediction accuracy in RMS displacement and vibration frequency compared to the corresponding initial models. In contrast, the integrated model that updates simultaneously using multiple conditions exhibits comparatively lower predictive performance relative to models dedicated to specific single conditions for accommodating the conflicting uncertain characteristics across all conditions. Nevertheless, the multi-condition model still reduces the prediction error by more than 45% compared to the initial model.

立管涡激振动不可避免地受到环境和结构参数等各种不确定性因素的影响，导致预测响应与实际响应存在较大偏差。为了提高隔水管的动态响应预测精度，提出了一种新的隔水管涡激振动模型更新方法。基于欧拉-伯努利梁理论建立了三维涡动分析模型，采用范德波尔尾迹振荡器计算了水动力载荷。采用Morris全局灵敏度分析方法识别关键参数，并结合粒子群优化（PSO）算法建立模型更新程序。通过VIV实验验证了该方法的有效性，并进一步研究了模型在单流和多流条件下的自适应更新特性。结果表明，与初始模型相比，针对每种工况分别更新的涡激振动模型在RMS位移和振动频率方面的预测精度显著提高。相比之下，使用多个条件同时更新的集成模型相对于用于适应所有条件中冲突的不确定特征的特定单一条件的模型显示出相对较低的预测性能。尽管如此，与初始模型相比，多条件模型仍将预测误差降低了45%以上。

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引用次数: 0

Hydrodynamic drag reduction and wave energy transfer of duck-swarm-inspired multi-catamaran formations 鸭群启发的多双体船结构的水动力减阻和波能传递

IF 5.5 2区工程技术 Q1 ENGINEERING, CIVIL

Ocean Engineering

Pub Date : 2026-04-15 Epub Date: 2026-02-06 DOI: 10.1016/j.oceaneng.2026.124523

Zhifan Zhang , Bo Jiang , Hechuan Zhang , Wei Wang , Shengren Wei , Jiuyang Cang , Guiyong Zhang

Energy conservation and drag reduction for ships represent a crucial research direction in the green development of the shipping industry and the field of marine engineering. While bio-inspired drag reduction is well-studied for monohulls, its application to catamarans remains complex due to inherent demihull interference. The concept of drag reduction for multi-catamaran formation navigation is proposed, and the effects of different vessel numbers, formation configurations, and relative spacing on formation resistance are systematically investigated. By analyzing the hull surface pressure distribution, free surface wave characteristics, and the law of wave transmission between catamarans, the physical mechanisms of wake superposition and wave interference in catamaran formations are revealed. The study finds that the suction effect generated in the wave trough region formed by the wake of the leading catamaran, and the constructive interference between the traveling waves of the following catamaran and the wake, constitute the key mechanisms for drag reduction. In the tandem formation, when the following catamaran is positioned at the dynamic equilibrium spacing within the suction zone of the wave trough in the leading catamaran's wake, the maximum drag reduction rate of the formation can reach 36.88%. When the longitudinal spacing is 1 L, all three layouts can achieve favorable drag reduction benefits.

船舶节能减阻是航运业和海洋工程领域绿色发展的一个重要研究方向。虽然生物动力减阻技术在单体船上的应用已经得到了很好的研究，但由于半船体固有的干扰，它在双体船上的应用仍然很复杂。提出了多双体船编队航行减阻的概念，系统研究了不同船数、编队构型和相对间距对编队阻力的影响。通过对船体表面压力分布、自由表面波特性和双体体间波浪传递规律的分析，揭示了双体体编队中尾流叠加和波浪干涉的物理机制。研究发现，前轮双体船尾迹形成的波槽区产生的吸力效应，以及后轮双体船行波与尾迹的相长干涉是减阻的关键机理。在串串编队中，当后面的双体船位于前轮双体船尾流波槽吸力区域内的动态平衡间距时，该编队的最大减阻率可达36.88%。当纵向间距为1 L时，三种布局均能获得较好的减阻效果。

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引用次数: 0