Article
Engineering, Marine
Xiaosen Xu, Fang Wang, Oleg Gaidai, Arvid Naess, Yihan Xing, Junlei Wang
Summary: This study presents an efficient Monte Carlo based method to study bivariate extreme dynamic response statistics in the context of FOWT design. The ACER2D method enables accurate and efficient predictions of extreme return period contours, which can help optimize FOWT design values and reduce structural production costs.
Article
Engineering, Marine
Diane Scicluna, Claire De Marco Muscat-Fenech, Tonio Sant, Giuliano Vernengo, Tahsin Tezdogan
Summary: This paper provides a detailed analysis of the hydrostatic stability characteristics of a novel floating wind turbine concept. The study focuses on offshore wind resources with water depths greater than 100 m and validates the theoretical calculations using SESAM. The results show that the floating structure exhibits hydrostatic stability characteristics that comply with industry standards.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2022)
Article
Engineering, Marine
Tomoki Ikoma, Lei Tan, Satsuya Moritsu, Yasuhiro Aida, Koichi Masuda
Summary: This study investigates the motion responses of a barge-type floating system with a vertical-axis wind turbine under different wave conditions, revealing that turbine rotations can reduce first-order sway and roll motion amplitudes while having little influence on first-order heave motion; furthermore, it is found that the increasing rotating speed of the turbine may significantly amplify second-order motion responses and mooring tether tensions.
Article
Engineering, Marine
Gayathry Rajiv, Mohit Verma, A. Subbulakshmi
Summary: This paper discusses the complexity of the dynamics of floating offshore wind turbines and proposes the use of Gaussian process metamodels for representing the hydrodynamics and structural dynamics of the floating platform. Three different Gaussian process metamodels are considered and compared in terms of evaluation indices, convergence, residuals and computational efficiency. The results show that all three Gaussian process metamodels are effective in emulating the response of the platform and can be used in situations where simple and computationally inexpensive models are required.
Article
Green & Sustainable Science & Technology
Yang Zhou, Qing Xiao, Yuanchuan Liu, Atilla Incecik, Christophe Peyrard, Decheng Wan, Guang Pan, Sunwei Li
Summary: The present study investigates the effect of turbulent wind and shear wind on the structure of a floating offshore wind turbine using a high-fidelity computational fluid dynamics method. The study demonstrates that turbulent wind causes fluctuations in rotor thrust and power outputs, and results in faster wake diffusion compared to time-independent inflow wind. Wind shear exacerbates the decrease in local minimum thrust/power. However, under the current wind inflow conditions, neither turbulent wind nor wind shear significantly affect the inline surge force, dynamic motion, and mooring tension of the floater.
Article
Green & Sustainable Science & Technology
Jianbing Chen, Zenghui Liu, Yupeng Song, Yongbo Peng, Jie Li
Summary: This paper presents a scaled model experiment of a spar-type floating offshore wind turbine (FOWT) and proposes an optimal arrangement scheme for anemometers deployment to improve wind field measurement efficiency. Load case tests are conducted to capture the rigid-body motion of the FOWT model, tower deformation, and mooring tension. The experiment reveals the influence of the rotor on yaw and the dominance of aerodynamic loads and hydrodynamic loads on the trend and amplitude of structural rigid-body motion, respectively. The resonant response caused by doubling frequency coupling effects in the flexible tower is also significant. The experiment serves as a benchmark for the validation of numerical simulation tools for FOWTs.
Article
Engineering, Marine
Fanxu Zeng, Ningchuan Zhang, Guoxing Huang, Qian Gu, Meng He
Summary: This study conducted experiments to investigate the dynamic response of a floating offshore wind turbine (FOWT) under freak wave actions. Various freak wave profiles were generated in a wave basin and their effects on the FOWT were measured and analyzed. The findings of this study provide insights for the design of FOWT and benchmarks for validating numerical models.
Article
Engineering, Marine
Xifeng Gao, Xiaoyong Liu, Xutian Xue, Nian-Zhong Chen
Summary: This paper summarized a study on the applicability of a fracture mechanics-based approach for calculating the fatigue lives of mooring lines of a floating offshore wind turbine. The results showed that the approach provides a reasonable estimate of fatigue lives and is sensitive to stress concentration factor and initial crack size. Parametric studies and comparative analysis of different mooring designs were conducted to further investigate the effects and applicability of each design.
Article
Engineering, Marine
Yiming Zhou, Yajun Ren, Wei Shi, Xin Li
Summary: Tension leg platform (TLP) is a cost-effective and high-performance support structure for floating offshore wind turbine (FOWT). This paper describes a newly proposed Braceless-TLP FOWT designed for a moderate water depth, and evaluates its performance under different weather conditions through numerical simulations.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2022)
Review
Engineering, Marine
Decao Yin, Elizabeth Passano, Fengjian Jiang, Halvor Lie, Jie Wu, Naiquan Ye, Svein Saevik, Bernt J. Leira
Summary: This study conducted a state-of-the-art review on influential VIM research, focusing on engineering practice, model tests, numerical calculation, and field measurement. Engineering gaps and potential research topics were identified for future work.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2022)
Article
Thermodynamics
Hyebin Lee, Sunny Kumar Poguluri, Yoon Hyeok Bae
Summary: Vertical axis wind turbines (VAWT) have a lower center of mass due to the placement of mechanical systems at the bottom of the tower, resulting in more stable motions in offshore environments. However, torque effects lead to continuous loading of the tower, constant platform motions, and increased mooring tension. A contra-rotating VAWT is adopted to mitigate these effects by counterbalancing the torque produced by the two rotors.
Article
Green & Sustainable Science & Technology
Yize Guo, Xiaodong Wang, Yuanhang Mei, Zhaoliang Ye, Xiaojiang Guo
Summary: This paper investigates the impact of platform pitch and surge motion coupling on the aerodynamic characteristics of floating offshore wind turbines (FOWTs). The results show that the coupling of these motions makes the wind turbine operation more unstable and leads to significant power and thrust fluctuations. The initial phase difference between the motions affects the instantaneous power more significantly than the instantaneous thrust. However, the effect on the average power and thrust values is weaker. When the initial phase difference results in reverse coupling of the motions, the fluctuation of power and thrust is reduced, leading to a more stable and safer wind turbine operation.
Article
Engineering, Civil
Tingsen Zheng, Nian-Zhong Chen, Lin Yuan
Summary: A framework is proposed for the structural strength assessment of the thin-walled blade root joint of a floating offshore wind turbine (FOWT). The framework includes calculation of loading on the blade root using time-domain dynamic analysis, consideration of interaction effects between joint components, and analysis of strength and failure using finite element method and Tsai-Hill and Tsai-Wu criteria. The effects of design and installation factors on the structural strength of the blade root joint are investigated.
THIN-WALLED STRUCTURES
(2023)
Article
Engineering, Marine
S. Muggiasca, F. Taruffi, A. Fontanella, S. Di Carlo, H. Giberti, A. Facchinetti, M. Belloli
Summary: Multi-purpose offshore structures are complex systems that require consideration of various requirements simultaneously. Experimental tests on scaled models are useful for verifying structural behavior and validating numerical models, with the scale playing a key role in obtaining reliable results. This paper focuses on the design of a wind turbine model for a large-scale model of a Multi-purpose offshore Platform developed within the EU project H2020 Blue Growth Farm, aiming to develop an offshore farm integrating wave energy converters, a wind turbine, and aquaculture.
Article
Engineering, Marine
Xiaoqian Wang, Zihua Zhang, Ping Zhuge
Summary: This study proposes a new anti-typhoon full submersible platform that combines the advantages of carbon-fiber-reinforced polymer tendons and various types of floating wind turbine foundations, showing promising potential and competitiveness in offshore wind structures.
Article
Energy & Fuels
Luis A. Martinez-Tossas, Philip Sakievich, Matthew J. Churchfield, Charles Meneveau
Summary: This work revisits the filtered lifting line theory and provides a more general formulation for solving flow problems with significant changes in chord, such as wind turbine blades.