Applied Ocean Research最新文献_第5页

Analysis of subsidence patterns of the formation around the wellbore during deepwater natural gas hydrate test production conditions 深水天然气水合物试采条件下井筒周围地层下沉模式分析

IF 4.3 2区工程技术 Q1 ENGINEERING, OCEAN

Applied Ocean Research

Pub Date : 2024-10-08 DOI: 10.1016/j.apor.2024.104257

Deep-water natural gas hydrates are commonly found in muddy siltstone at shallow seabed depths. The land subsidence caused by the continuous dissociation of hydrate can influence the stability of the subsea wellhead and facilities. The analysis of formation subsidence pattern around wellbore is helpful to avoid the risk of field operation. A multi-field coupled model for hydrate extraction experiments was established, considering the coupling effects of seepage, mechanical, thermal, and chemical fields based on the storage characteristics of hydrates and the properties of submarine soils. Based on the formation physical parameters and wellbore parameters of the Shenhu area in the South China Sea, a numerical simulation method was used to analyze the formation subsidence pattern around the wellbore under hydrate production test conditions, and a sensitivity analysis of subsidence factors was completed. According to the subsidence patterns obtained, combined with the field operation conditions, the hazardous loads on the conductor throughout its lifecycle during the hydrate production test process were analyzed. A design method for the minimum mud depth of the conductor under hydrate production test conditions was provided. The study of seabed subsidence patterns during natural gas hydrate production tests in deep-water sea is helpful in reducing the instability risk of subsea wellheads and ensuring operation security, which provides a certain of reference for the design of natural gas hydrate production test engineering.

深水天然气水合物通常存在于浅海海底的泥质粉砂岩中。水合物不断解离造成的陆地沉降会影响海底井口和设施的稳定性。对井筒周围地层下陷模式的分析有助于规避油田作业风险。根据水合物的存储特性和海底土壤的属性，考虑渗流、机械、热和化学场的耦合效应，建立了水合物提取实验的多场耦合模型。根据南海神狐地区的地层物理参数和井筒参数，采用数值模拟方法分析了水合物开采试验条件下井筒周围地层的下沉规律，并完成了下沉因素的敏感性分析。根据得到的下沉规律，结合现场作业条件，分析了水合物生产试验过程中导体在整个生命周期内的危险载荷。提供了水合物生产试验条件下导体最小泥浆深度的设计方法。对深水海域天然气水合物生产试验过程中海底沉降规律的研究，有助于降低海底井口失稳风险，确保作业安全，为天然气水合物生产试验工程设计提供了一定的参考。

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引用次数: 0

The impact performance of concrete-filled double-skin steel tubes under seawater corrosion: A review 混凝土填充双层钢管在海水腐蚀下的抗冲击性能：综述

IF 4.3 2区工程技术 Q1 ENGINEERING, OCEAN

Applied Ocean Research

Pub Date : 2024-10-07 DOI: 10.1016/j.apor.2024.104248

The study of the impact resistance of concrete-filled double-skin steel tube structures in the ocean environment is essential to ensuring the safety and reliability of ocean engineering structures, and it can also promote technological progress and industrial development in related fields. Thus, this review focuses on the effect of seawater corrosion on the impact performance of concrete-filled double-skin steel tube structural members. The effects of seawater corrosion on the tensile, compressive, and hysteretic properties of steel are first summarized. Secondly, the corrosion test methods currently used in most tests, such as salt spray, immersion, and artificially accelerated corrosion, are reviewed. The research progress on the impact performance of concrete-filled double-skin steel tube members, joints and corroded concrete-filled double-skin steel tube structures is then systematically summarized. Such members mainly absorb impact through overall bending deformation. The hollow ratio, boundary conditions and other factors strongly influence their impact performance. Corrosion of course weakens the impact properties. Recommendations for further study on the impact performance of seawater-corroded steel structures are provided.

研究海洋环境中混凝土填充双层钢管结构的抗冲击性能，对于确保海洋工程结构的安全性和可靠性至关重要，同时也能促进相关领域的技术进步和产业发展。因此，本综述重点讨论海水腐蚀对混凝土填充双层钢管结构构件抗冲击性能的影响。首先总结了海水腐蚀对钢材拉伸、压缩和滞后特性的影响。其次，综述了目前大多数试验中使用的腐蚀试验方法，如盐雾、浸泡和人工加速腐蚀。然后，系统总结了混凝土填充双层钢管构件、接头和腐蚀混凝土填充双层钢管结构冲击性能的研究进展。此类构件主要通过整体弯曲变形吸收冲击力。中空比、边界条件和其他因素对其冲击性能有很大影响。腐蚀当然会削弱其冲击性能。本文提出了进一步研究海水腐蚀钢结构冲击性能的建议。

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引用次数: 0

Numerical and experimental study of asymmetrical wave loads and hydroelastic responses of ship in oblique regular waves 非对称波浪载荷和船舶在斜向规则波浪中的水弹性响应的数值和实验研究

IF 4.3 2区工程技术 Q1 ENGINEERING, OCEAN

Applied Ocean Research

Pub Date : 2024-10-05 DOI: 10.1016/j.apor.2024.104254

In this paper, the global motions and wave loads on a large bow-flare ship in oblique regular waves considering hydroelastic effects are studied both numerically and experimentally. Numerical simulations of the ship's asymmetrical motions and loads in waves are conducted using a CFD-FEM two-way coupled method. The segmented model tank test is also conducted by using a hybrid structural backbone beam to measure both the sectional vertical bending moment and torsional moment. The numerical results are verified and validated by analyzing the ship modal behaviour, roll free decay curve, motions and loads and comparing with the experiment results. The influence of wave heading angle, wave length, wave height and ship speed on the wave loads including sectional bending moment and torsion moment are comprehensively studied with the numerical and experimental results. The relationship among vertical bending moment, horizontal bending moment and torsion moment is also discussed.

本文从数值和实验两方面研究了考虑到水弹性效应的倾斜规则波浪中大型艏侧帆船的全局运动和波浪载荷。采用 CFD-FEM 双向耦合方法对船舶在波浪中的不对称运动和载荷进行了数值模拟。此外，还使用混合结构骨架梁进行了分段模型油舱试验，以测量断面垂直弯矩和扭转力矩。通过分析船舶模态行为、自由滚动衰减曲线、运动和载荷，并与实验结果进行比较，对数值结果进行了验证和确认。结合数值和实验结果，全面研究了波向角、波长、波高和船速对波浪载荷（包括截面弯曲力矩和扭转力矩）的影响。还讨论了垂直弯矩、水平弯矩和扭转力矩之间的关系。

引用次数: 0

Dynamic behavior of piled jacket offshore wind turbines based on integrated aero-servo-hydro-SSI-OWT model 基于集成航空-伺服-水力-SSI-OWT 模型的桩式护套海上风力涡轮机的动态特性

IF 4.3 2区工程技术 Q1 ENGINEERING, OCEAN

Applied Ocean Research

Pub Date : 2024-10-05 DOI: 10.1016/j.apor.2024.104255

Jacket foundation is typically the preferred choice for Offshore Wind Turbines (OWTs) erected in water depth varying from 40 m to 80 m. In this paper, an integrated dynamic analysis model is designed to study the coupling between aerodynamics, servodynamics, hydrodynamics, soil-structure interaction for piled jacket OWTs. The performances of the AeroDyn and ServoDyn modules are verified by FAST, showcasing their applicability under deterministic and stochastic environmental conditions. The OWT dynamic responses, especially for t-z modeling, stress-transfer mechanism and structural fatigue damage, are subsequently studied. The overall deformation of the jacket calculated by the nonlinear elastic t-z curve in the API guideline, is overwhelmed by the t-z curve formulated using bounding surface plasticity framework, due to the ignorance of the loading history effect. Accompanied by a “compressed-released-recompressed” stress-transfer process, the downwind tube would experience high stress level, hence necessitating more attention in the ultimate limit state design of piled jacket structure. Otherwise, the upwind tube seems to be more decisive to the fatigue limit state design of piled jacket structure, owing to severe fluctuation in structural stress caused by a “tensed-released-re-tensed” stress-transfer tendency.

本文设计了一个综合动态分析模型，用于研究桩式夹套海上风电机组的空气动力学、伺服动力学、流体力学和土壤-结构相互作用之间的耦合。FAST 验证了 AeroDyn 和 ServoDyn 模块的性能，展示了它们在确定性和随机环境条件下的适用性。随后研究了 OWT 的动态响应，特别是 t-z 建模、应力传递机制和结构疲劳损伤。由于忽略了加载历史效应，根据 API 准则中的非线性弹性 t-z 曲线计算出的夹套整体变形被利用边界表面塑性框架制定的 t-z 曲线所压倒。伴随着 "压缩-释放-压缩 "的应力传递过程，下风管将承受高应力水平，因此有必要在桩套结构的极限状态设计中给予更多关注。相反，上风管由于 "张紧-释放-张紧 "的应力传递趋势导致结构应力剧烈波动，似乎对桩套结构的疲劳极限状态设计更具决定性。

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引用次数: 0

Hydrodynamic optimization and performance verification of fairings for round-ended cofferdams using dam-break wave experiments and numerical simulations 利用溃坝波实验和数值模拟对圆端围堰的整流罩进行水动力优化和性能验证

IF 4.3 2区工程技术 Q1 ENGINEERING, OCEAN

Applied Ocean Research

Pub Date : 2024-10-04 DOI: 10.1016/j.apor.2024.104247

Round-ended cofferdams are crucial for large-scale marine projects but are vulnerable to the complex marine environment, including waves, tides, and storms. Enhancing the hydrodynamic performance of these cofferdams is essential for improving safety and efficiency in marine construction. This study introduces a novel fairing design aimed at reducing water flow resistance during the quasi-stable stage of a tsunami. The flow field is analyzed using computational fluid dynamics (CFD) simulations, and an adaptive surrogate model is employed to optimize the parameterized fairing shape. The results demonstrate that the optimized shape significantly suppresses vortex shedding, leading to a 16.59 % reduction in the drag coefficient and a 44.3 % reduction in the lift coefficient under flow conditions. Experimental and numerical simulations of dam-break waves are conducted for two designs, R1 and R0. By comparing their flow field and force characteristics, it is found that R1 effectively separates waves during the impulse stage, reduces wave climb height, and decreases impact loads. In the quasi-stable stage, R1 mitigates the blockage effect, reducing the liquid level difference between the front and back, and thus lowering flow forces. Experimental data further reveals that when the downstream is a dry riverbed, R1′s load reduction is particularly notable, with maximum reductions of 45.62 % in the impulse stage and 28.75 % in the quasi-stable stage. When the riverbed is wet, the maximum load reduction rates are 18.04 % and 8.72 %, respectively. Therefore, R1 not only reduces the resistance of round-end cofferdams under water currents but also under extreme wave forces, providing valuable insights for advancing ocean engineering design.

圆形围堰对大型海洋工程至关重要，但容易受到海浪、潮汐和风暴等复杂海洋环境的影响。增强这些围堰的水动力性能对于提高海洋施工的安全性和效率至关重要。本研究介绍了一种新型整流罩设计，旨在减少海啸准稳定阶段的水流阻力。利用计算流体动力学（CFD）模拟分析了流场，并采用自适应代用模型优化了参数化的整流罩形状。结果表明，优化后的整流罩形状能显著抑制涡流脱落，从而使流动条件下的阻力系数降低了 16.59%，升力系数降低了 44.3%。对 R1 和 R0 两种设计进行了溃坝波的实验和数值模拟。通过比较它们的流场和受力特性，发现 R1 在冲击阶段能有效地分离波浪，降低波浪爬升高度，减少冲击载荷。在准稳定阶段，R1 可减轻阻塞效应，减少前后液面差，从而降低流力。实验数据进一步表明，当下游为干燥河床时，R1 的减载效果尤为显著，在冲击阶段最大减幅为 45.62%，在准稳定阶段最大减幅为 28.75%。当河床潮湿时，最大荷载降低率分别为 18.04 % 和 8.72 %。因此，R1 不仅能减小圆端围堰在水流作用下的阻力，还能减小其在极端波浪力作用下的阻力，为推进海洋工程设计提供了宝贵的启示。

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引用次数: 0

Study of the dynamic response of an offshore continuous beam bridge under nonlinear wave and scour 非线性波浪和冲刷下离岸连续梁桥的动态响应研究

IF 4.3 2区工程技术 Q1 ENGINEERING, OCEAN

Applied Ocean Research

Pub Date : 2024-10-04 DOI: 10.1016/j.apor.2024.104245

The study highlights the critical factors and findings regarding bridge damage susceptibility during typhoons and hurricanes, primarily due to extreme waves, scour, and storm surges. While existing research has extensively studied bridges' responses to either extreme waves or scour individually, their combined effects have not been sufficiently explored. Experiments were conducted on a scaled two-span bridge to examine its behavior under simultaneous wave and scour conditions. Results from these experiments indicate that as scour depth increases, there is a corresponding escalation in displacement of the bridge pier, acceleration of the bearing platform, and strain along the pile foundation. To further investigate these dynamics, fluid-structure interaction analysis was employed, revealing significant insights. Notably, the study found that wave height exerts a substantial influence on wave load. For instance, at a wave height of 6 m, the average peak horizontal wave load on bridge piers was 2.48 times higher than at 3 m wave height. Moreover, local scour was identified as a critical factor reducing the bearing capacity of pile foundations, thereby significantly impacting the bridge's dynamic response to nonlinear waves. Under identical wave conditions, varying scour depths (3 m, 6 m, 9 m, and 12 m) resulted in increases in peak lateral displacements at the pier top compared to non-scouring conditions. The study concludes by emphasizing the increasing risk posed to pile foundations with deeper scour depths, particularly under stronger wave conditions. Consequently, there is a crucial need to enhance the resilience of offshore bridges against these dual hazards through advanced design and protective measures.

该研究强调了台风和飓风期间桥梁易受损坏的关键因素和发现，主要是由于极端波浪、冲刷和风暴潮造成的。虽然现有研究已广泛研究了桥梁对极端波浪或冲刷的单独响应，但对它们的综合影响还没有进行充分的探讨。我们在一座按比例缩放的两跨桥梁上进行了实验，以研究其在波浪和冲刷同时作用条件下的行为。实验结果表明，随着冲刷深度的增加，桥墩的位移、承台的加速度和桩基的应变也会相应增加。为了进一步研究这些动态变化，采用了流体-结构相互作用分析，并获得了重要启示。值得注意的是，研究发现波浪高度对波浪荷载有很大影响。例如，波高 6 米时，桥墩上的平均峰值水平波载荷是波高 3 米时的 2.48 倍。此外，局部冲刷被认为是降低桩基承载力的关键因素，从而极大地影响了桥梁对非线性波浪的动态响应。在相同的波浪条件下，不同的冲刷深度（3 米、6 米、9 米和 12 米）导致桥墩顶部的峰值侧向位移比无冲刷条件下有所增加。研究最后强调，随着冲刷深度的加深，尤其是在较强的波浪条件下，桩基所面临的风险会越来越大。因此，亟需通过先进的设计和保护措施来增强近海桥梁对这些双重危害的抵御能力。

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引用次数: 0

Theory for plunger-type wavemakers to generate second-order Stokes waves and Smoothed Particle Hydrodynamics verification 产生二阶斯托克斯波的柱塞式造浪机理论和平滑粒子流体力学验证

IF 4.3 2区工程技术 Q1 ENGINEERING, OCEAN

Applied Ocean Research

Pub Date : 2024-10-04 DOI: 10.1016/j.apor.2024.104244

Plunger-type wavemakers are used in ocean engineering laboratories globally. However, the wave-making theories remain incomplete due to the complex geometries of the plungers. This work derives the motion equations for an arbitrary-geometry plunger to generate second-order Stokes waves, along with the generic constraints on wave parameters. Taking wedge-shaped and cylinder-shaped plungers as examples, the motion equations and constraints are detailed. Subsequently, a smoothed particle hydrodynamics (SPH) model for the plunger-induced waves is established and validated by accurately reproducing published experimental results. Finally, the SPH model is applied to simulate the wave generation by the two plungers. The computed wave profiles, water pressures, and flow velocities are compared with their analytical solutions in terms of spatial distribution and time history. Additionally, the wave field stability and the wave generation process are evaluated. The results demonstrate that second-order Stokes waves with target waveforms can be precisely generated using an arbitrary-geometry plunger-type wavemaker within a short transition distance and time, thereby verifying the reliability of the proposed wavemaker theory.

全球的海洋工程实验室都在使用柱塞式造浪机。然而，由于柱塞的几何形状复杂，造浪理论仍不完整。本研究推导了任意几何柱塞产生二阶斯托克斯波的运动方程，以及波参数的通用约束条件。以楔形和圆柱形柱塞为例，详细介绍了运动方程和约束条件。随后，建立了柱塞诱导波的平滑粒子流体力学（SPH）模型，并通过精确再现已发表的实验结果进行了验证。最后，应用 SPH 模型模拟了两个柱塞产生的波浪。计算得出的波浪剖面、水压和流速在空间分布和时间历程方面与分析解进行了比较。此外，还对波场稳定性和波产生过程进行了评估。结果表明，使用任意几何柱塞式造浪机可以在很短的过渡距离和时间内精确地产生具有目标波形的二阶斯托克斯波，从而验证了所提出的造浪机理论的可靠性。

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引用次数: 0

Two-dimensional one-way coupled modelling for fluid-structure-seabed interactions around a semicircular breakwater using OpenFOAM 利用 OpenFOAM 建立半圆形防波堤周围流体-结构-海床相互作用的二维单向耦合模型

IF 4.3 2区工程技术 Q1 ENGINEERING, OCEAN

Applied Ocean Research

Pub Date : 2024-10-01 DOI: 10.1016/j.apor.2024.104249

Semicircular breakwaters, preferred for their lighter weight, wider base and superior resistance to overturning and sliding, have seen focused research on wave forces and hydrodynamic performance. Despite documented failures due to seabed instability, numerical examinations of the seabed response and stability around these structures are lacking in the literature. This study establishes an OpenFOAM model to numerically investigate hydrodynamic interactions, structural dynamics, seabed consolidation and liquefaction potential near a semicircular breakwater in two-dimensional, addressing complex fluid–structure-seabed interactions in a one-way coupling manner. A novel method for determining the compressibility of the pore fluid has been implemented, which integrates geostatic stress, atmospheric pressure and wave-induced excessive pore pressure within the seabed. The numerical results indicate that seabed responses are sensitive to the bulk modulus of pore air in partially saturated cases, where a decrease in pore pressure, an increase in the vertical effective stress and a decrease in the horizontal effective stress are observed. Further numerical analysis reveals that the most vulnerable part of the breakwater appears on the wave-facing side of the caisson, where reinforcement measurements are recommended during construction. A pronounced liquefaction zone is observed ahead of the breakwater, corresponding to the area with upward seepage, which is attributed to the combined effect of hydrodynamic interactions and direct stress action transferred from the semicircular breakwater.

半圆形防波堤因其重量轻、底座宽、抗倾覆和抗滑动性能优越而备受青睐，其波浪力和流体力学性能一直是研究的重点。尽管由于海床不稳定性而导致失败的案例屡见不鲜，但文献中缺乏对这些结构周围海床响应和稳定性的数值研究。本研究建立了 OpenFOAM 模型，对半圆形防波堤附近的水动力相互作用、结构动力学、海床固结和液化潜力进行二维数值研究，以单向耦合的方式解决复杂的流体-结构-海床相互作用问题。采用了一种确定孔隙流体可压缩性的新方法，该方法综合了海床内的静地应力、大气压力和波浪引起的过大孔隙压力。数值结果表明，在部分饱和的情况下，海底反应对孔隙空气的体积模量很敏感，可以观察到孔隙压力减小、垂直有效应力增大和水平有效应力减小。进一步的数值分析表明，防波堤最脆弱的部分出现在沉箱面向波浪的一侧，建议在施工期间对该处进行加固测量。在防波堤前方观察到一个明显的液化区，与上渗区域相对应，这归因于水动力相互作用和半圆形防波堤传递的直接应力作用的综合效应。

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引用次数: 0

Numerical investigation on the slamming loads of a truncated trimaran hull entering regular waves 截尾三体船船体进入规则波浪时的撞击载荷数值研究

IF 4.3 2区工程技术 Q1 ENGINEERING, OCEAN

Applied Ocean Research

Pub Date : 2024-10-01 DOI: 10.1016/j.apor.2024.104253

For ship slamming, waves can disturb the water entry progress and thus affect the slamming load characteristics. This paper studied the slamming loads of a trimaran entering regular waves based on the CFD method. The results of a trimaran model impacting calm water and wedge impacting waves are used to verify the present method. The free surface evolution and load characteristics of the trimaran model considering wave effects are discussed. The results showed that the position at which the structure touches the wave surface depends on the formation, deformation and escape of bubble flows, which cause obvious asymmetrical flow. The enclosure of the air cavity induces a step increase in pressure, and the pressure peak appears when the bubble fully escapes. Three typical positions, wave crest, wave cross and wave through, are chosen to explore the influence of waves on slamming loads. The impact load shows a 98% difference at different wave locations. In ship load forecasting, the position of the waves relative to the hull is noteworthy. The influence of the water entry velocity on the slamming load is further discussed. Bubble retention related to the water entry velocity is the key factor affecting the peak load.

对于船舶撞击而言，波浪会干扰入水过程，从而影响撞击载荷特性。本文基于 CFD 方法研究了三体船进入规则波浪时的撞击载荷。三体船模型冲击平静水域和楔形冲击波的结果用于验证本方法。讨论了考虑波浪效应的三体船模型的自由表面演变和载荷特性。结果表明，结构接触波浪表面的位置取决于气泡流的形成、变形和逃逸，从而导致明显的不对称流动。气腔的封闭导致压力阶跃上升，当气泡完全逸出时出现压力峰值。选取波峰、波跨和波穿三个典型位置，探讨波浪对撞击载荷的影响。不同波浪位置的冲击载荷相差 98%。在船舶载荷预报中，波浪相对于船体的位置值得注意。进一步讨论了入水速度对撞击载荷的影响。与进水速度有关的气泡滞留是影响峰值载荷的关键因素。

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引用次数: 0

A semi-analytical approach for dynamic responses of monopile-supported offshore wind turbines subjected to accidental loads 单桩支撑海上风力涡轮机在意外荷载作用下动态响应的半分析方法

IF 4.3 2区工程技术 Q1 ENGINEERING, OCEAN

Applied Ocean Research

Pub Date : 2024-09-28 DOI: 10.1016/j.apor.2024.104251

Offshore wind energy is leading the way in sustainable energy generation. Offshore wind turbines (OWTs) need to be designed to withstand extreme or accidental loads in Ultimate Limit States (ULS) and Accidental Limit States (ALS), whereby high order eigenmodes may become significant. This paper introduces a semi-analytical approach for efficient and reliable analysis of the dynamic responses of monopile-supported OWTs subjected to accidental loads. A Rayleigh-Ritz solution is initially adopted to determine the high-order natural frequencies and eigenmodes of monopile OWTs, explicitly considering tapered towers and soil-pile interactions. Dynamic responses of OWTs are then calculated depending on the interaction schemes between accidental loads and the structures, e.g. soft contact loads (e.g. slamming, wind) and hard contact loads (e.g. ship collisions, ice impact). For soft contact loading conditions, the loads are considered independent of turbine responses, and the transient dynamic response is computed using the classical modal superposition method. While for hard contact loading conditions, the load actions depend on the contact stiffnesses and responses of the interacting bodies. A numerical contact algorithm is thus developed, and numerical iterations are performed to ensure convergence. The proposed approach is applied to the DTU 10 MW monopile-supported OWT subjected to extreme water slamming and ship collisions, respectively as example applications of soft and hard contact scenarios. The results are verified against nonlinear finite element analysis using USFOS and discussed with respect to the turbine natural frequencies and eigenmodes, contact forces and dynamic responses. A parametric analysis is conducted for ship-OWT collisions, exploring different impact scenarios by varying ship sizes, contact stiffnesses, and initial impact velocities. The proposed approach can serve as a promising tool for accidental load response analysis and the design of monopile OWTs.

海上风能正在引领可持续能源生产。海上风力涡轮机（OWT）的设计需要能够承受极限状态（ULS）和意外极限状态（ALS）下的极端或意外载荷，其中高阶特征模态可能变得非常重要。本文介绍了一种半分析方法，用于高效可靠地分析单桩支撑 OWT 在意外荷载作用下的动态响应。首先采用 Rayleigh-Ritz 解法确定单桩式单臂塔的高阶固有频率和特征模态，并明确考虑锥形塔和土桩相互作用。然后，根据意外荷载与结构之间的相互作用方案，如软接触荷载（如撞击、风）和硬接触荷载（如船舶碰撞、冰面冲击），计算 OWT 的动态响应。在软接触荷载条件下，荷载与水轮机响应无关，瞬态动态响应采用经典的模态叠加法计算。而对于硬接触加载条件，载荷作用取决于相互作用体的接触刚度和响应。因此开发了一种数值接触算法，并进行数值迭代以确保收敛。作为软接触和硬接触的应用实例，所提出的方法被应用于 DTU 10 MW 单桩支撑 OWT，该 OWT 分别受到极端水流冲击和船舶碰撞的影响。结果与使用 USFOS 进行的非线性有限元分析进行了验证，并就水轮机固有频率和特征模式、接触力和动态响应进行了讨论。针对船舶-OWT 碰撞进行了参数分析，通过改变船舶尺寸、接触刚度和初始撞击速度来探索不同的撞击情景。所提出的方法可作为事故载荷响应分析和单桩式水下风车设计的有效工具。

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引用次数: 0