Article
Energy & Fuels
Sepideh Kianbakht, Dana Martin, Kathryn Johnson, Daniel Zalkind, Lucy Pao, Eric Loth, Juliet Simpson, Shulong Yao, Mayank Chetan, D. Todd Griffith
Summary: Wind turbine design involves various aspects such as aerodynamics, structure, electrical, and control system design. A system design approach is used to evaluate and quantify the overall performance of the wind turbine during operational scenarios and subsystem interactions. This paper presents the design for a 50-MW Segmented Ultralight Morphing Rotor (SUMR) wind turbine, using levelized cost of energy (LCOE) for design choices and quantifying simulated performance shortcomings. The interdisciplinary design process results in a final ultra-scale turbine configuration that outperforms other existing offshore wind farms in terms of LCOE.
Article
Energy & Fuels
Jiangman Li, Jianlin Shen, Xiaoli Wang, Junjie Xu
Summary: This study focuses on the feasibility analysis of a wind power generation project, including core contents such as wind turbine selection, layout, and power generation estimation. After analyzing the specific needs of the Dayingpo project, a layout scheme was selected and recommendations were proposed based on the actual terrain and wind resources of the area.
Article
Engineering, Marine
Sungjun Park, Joonmo Choung
Summary: To design a floating offshore wind turbine, fully coupled integrated load analyses (ILAs) are required to evaluate the load response and structural integrity. This study aims to investigate the feasibility of using the direct strength analysis (DSA) technique, commonly used for ships and offshore structures, to properly evaluate the substructure of a floating offshore wind turbine (FOWT).
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2023)
Article
Engineering, Civil
Shuaishuai Wang, Yihan Xing, Rajiv Balakrishna, Wei Shi, Xiaosen Xu
Summary: This article presents and verifies an effective design method for floating wind turbine platforms, which considers the nonlinearity of the dynamics and provides reasonable internal stress for design checks. A steel semi-submersible platform is developed and analyzed with various checks and analyses. The dynamic behavior of the steel platform is evaluated by comparing it with concrete-support wind turbine models. The key findings and future design ideas are summarized, expanding the engineering practice and research on floating wind turbine platforms.
ENGINEERING STRUCTURES
(2023)
Article
Green & Sustainable Science & Technology
F. Papi, A. Bianchini
Summary: This study critically analyzes the technical implications of upscaling in floating wind turbines, finding that overall performance and rotor loads are only marginally affected by floating installation, while tower loads are significantly affected by platform motions.
RENEWABLE & SUSTAINABLE ENERGY REVIEWS
(2022)
Article
Engineering, Marine
Daniel Gonzalez-Delgado, Pablo Jaen-Sola, Erkan Oterkus
Summary: The use of generative design as an alternative to traditional structural optimization techniques presents new possibilities in manufacturing. This study applied generative design techniques as an automated iterative process to explore and optimize the stiffness and weight of a 3 MW offshore wind turbine electrical generator structure. By integrating generative design into the structural optimization process, a 4% reduction in structural mass was achieved, and modifications to the structural geometry increased the machine's operational range and energy gathering capacity.
Article
Engineering, Marine
Carlos Eduardo Silva de Sousa, Erin E. Bachynski-Polic
Summary: This paper explores the impact of increasing size and power of floating wind turbines (FWTs) on their global responses, highlighting the differences from smaller units. The study emphasizes the significant influence of static pitch angle at rated thrust on platform dynamics and fatigue damage/extreme loads. Extreme stresses are largely affected by gravitational loads, with designs featuring larger pitch at rated thrust exhibiting the highest extreme stresses at the platform and most of the tower sections. Load cases associated with the rated wind speed generally govern extreme loads for the 20 MW FWTs, unlike previous studies with smaller units.
Article
Engineering, Marine
Shiqi Liu, Zhenju Chuang, Kai Wang, Xin Li, Xin Chang, Lixun Hou
Summary: The full exploitation of offshore wind resources is essential for meeting the massive energy demand. This study investigates the effect of structural parameters on the hydrodynamic performance of a semi-submersible floating foundation for a 15 MW offshore wind turbine. The results show that optimizing the design can lead to improved dynamic performance and reduced costs.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2022)
Article
Engineering, Marine
Nicola Pollini, Antonio Pegalajar-Jurado, Henrik Bredmose
Summary: We conducted an optimization study for the conceptual design of TetraSpar wind turbine floaters, optimizing all geometric dimensions of the floater, keel, mooring lines, and tower design. Our optimization method utilized a gradient-based approach with a mass proportional objective cost function, taking into account the weight components of the floater, wind turbine tower, and mooring system. We employed a frequency domain response method to consider dynamic response for different wind speeds and wave conditions. Constraint analysis revealed that the 3P tower frequency constraint played the most significant role in cost influence.
Article
Energy & Fuels
Irene Rivera-Arreba, Adam S. Wise, Mahe Hermile, Fotini K. Chow, Erin E. Bachynski-Polic
Summary: Global dynamic response models used for wind turbine design are often based on neutral stability, which is not representative of actual atmospheric conditions. This study examines the low-frequency content of the global responses of a semisubmersible floating wind turbine under stable, neutral, and unstable atmospheric stability conditions, using different wind generation models. The results show that both atmospheric stability and the turbulence wind model significantly affect the response of the wind turbine.
Article
Energy & Fuels
Ran Zhang, Lianxue Gao
Summary: This study focuses on the design technology of direct drive permanent magnet synchronous wind turbine, especially the semi-direct drive permanent magnet synchronous wind turbine. The power factor of the generator is improved by adding reactive power compensation device and filter circuit. The cogging torque and resistance torque of the generator are weakened by using the closed slot scheme and T-shaped rotor pole structure. The optimal design scheme is determined through comparative analysis.
Article
Engineering, Aerospace
Xiaoqi LI, Xiaoquan CHENG, Yujia CHENG, Zhiyong WANG, Wenjun HUANG
Summary: The research shows that HBB joint can provide multiple load transmission paths and resist damage propagation in the adhesive. Compared with pure bonded joint, HBB joint has higher strength and energy absorption capacity. In addition, HBB joint has greater initial damage load and tensile stiffness than pure bolted joint. Adhesive fillets can significantly improve the tensile performance of the HBB joint.
CHINESE JOURNAL OF AERONAUTICS
(2021)
Article
Engineering, Marine
Sebastien Gueydon, Frances M. Judge, Michael O'Shea, Eoin Lyden, Marc Le Boulluec, Julien Caverne, Jeremy Ohana, Shinwoong Kim, Benjamin Bouscasse, Florent Thiebaut, Sandy Day, Saishuai Dai, Jimmy Murphy
Summary: This paper documents a round robin testing campaign on a 1/60th scale model of a 10 MW floating wind turbine at four different locations in Europe. The focus was on hydrodynamic responses of a semi-submersible floating foundation, finding global surge stiffness comparable across facilities with differences in heave and pitch stiffness coefficients. Response Amplitude Operators showed similarities in motion shape globally, but differences were magnified around resonance and cancellation frequencies. Surge motions were significantly impacted by reflections leading to large differences between basins.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2021)
Article
Engineering, Marine
Xiaohan Fu, Meiping Sheng
Summary: The existing blade protection mechanisms for offshore wind turbines are highly dependent on the control system and its power supply, leading to potential safety risks under extreme weather conditions when the control protection mechanisms fail. This paper proposes a reinforcing cable component (RCC) to enhance the resistance ability of offshore wind turbine blades. Simulation and test results demonstrate that the RCC effectively reduces strain and tip displacement of the blades, thus improving their survival ability when the control protection system fails.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2022)
Article
Engineering, Marine
Xiangheng Feng, Yonggang Lin, Yajing Gu, Danyang Li, Bowen Chen, Hongwei Liu, Yong Sun
Summary: Platform motions induced by wind and waves have a strong nonlinear coupling effect on the aerodynamic characteristics of floating offshore wind turbines, which worsens the power instability of the turbine and should be considered in the early design stage. This study proposed a platform motion-based method to estimate power stability and successfully applied it to the preliminary stability design. A high-fidelity computational fluid dynamics model was established for a 10 MW wind turbine using oversetting grid and superposition motion technology. The influence of platform surge and pitch motions on the power characteristics of the turbine was summarized, and a semi-submersible platform structure was designed to support the turbine based on hydrodynamic analysis.
Article
Green & Sustainable Science & Technology
Ju Gao, D. Todd Griffith, Mohammad Sadman Sakib, Sung Youn Boo
Summary: The study explores the advantages of floating vertical axis wind turbines (VAWTs) over floating horizontal axis wind turbines (HAWTs) in deep water at large scales, and introduces a new 7-degree-of-freedom (7-DOF) model for assessing and predicting the performance of floating VAWTs.
Article
Energy & Fuels
Dongyang Cao, Sadeq Malakooti, Vijay N. Kulkarni, Yao Ren, Yingjian Liu, Xu Nie, Dong Qian, D. Todd Griffith, Hongbing Lu
Summary: The study highlights the importance of resin uptake in determining the flexural properties of sandwich composites used in wind turbine blades. It is found that different resin uptake levels can significantly impact the specific flexural strength and modulus of the composite materials. Additionally, the findings suggest that the failure mode of the sandwich composites is influenced by the core stiffness and surface texture, with different types of cores exhibiting different failure mechanisms.
Article
Energy & Fuels
Shulong Yao, Mayank Chetan, D. Todd Griffith, Alejandra S. Escalera Mendoza, Michael S. Selig, Dana Martin, Sepideh Kianbakht, Kathryn Johnson, Eric Loth
Summary: The need for lower levelized cost of energy has led to an increase in the size of wind turbines, with the largest published rotor design being 25 MW. This paper explores the feasibility of a 50 MW design, presenting aero-structural blade designs and addressing challenges for extreme-scale rotors. Through optimization and reduction of blade mass and cost, a 25% mass reduction and 30% cost reduction were achieved, improving aero-structural performance.
Article
Energy & Fuels
Mayank Chetan, M. Sadman Sakib, D. Todd Griffith, Abhineet Gupta, Mario A. Rotea
Summary: The paper presents a holistic design solution that integrates active load control using a controllable Gurney flap based on plasma actuators to reduce costs and improve efficiency of wind turbines. Results show significant reductions in loads, rotor mass, and LCOE through the implementation of this design solution. Additionally, extending active load control from Region-III to include Region-II further reduces DEL by 34%.
Article
Acoustics
Yuanchang Chen, D. Todd Griffith
Summary: This study investigates the dynamics and relative motions of wind turbine blade surfaces from both global and local perspectives using experimental and numerical methods. Experimental modal testing is conducted on the blade surfaces using a high spatial resolution 3D SLDV, and the resulting data is stitched together to build experimental mode shapes. A finite element model is developed to obtain numerical mode shapes, which are then validated using the experimental data. The study provides valuable case studies for the design and structural analysis of wind turbine blades.
JOURNAL OF VIBRATION AND CONTROL
(2023)
Article
Green & Sustainable Science & Technology
Stephen B. Johnson, Mayank Chetan, D. Todd Griffith, James Sherwood
Summary: Wind turbines play a significant role in electricity generation, with market share growth attributed to improvements in reliability, output, and cost efficiency. The length of wind blades affects output, with efforts to reduce blade costs. Research builds on process modeling to calculate labor costs, developing a detailed cost model for materials, overheads, and business operations, integrated into a techno-economic model for comprehensive calculation of blade manufacturing costs.
Article
Engineering, Multidisciplinary
Dongyang Cao, Dan Bouzolin, Hongbing Lu, Todd Griffith
Summary: This study explored the application of FDM printed core materials in sandwich composites. The compression-molding process was used to improve the skin/core interphase, and a connection between in-plane and out-of-plane shear properties was established using DIC. The feasibility of 3D printed cores in composite sandwich structures was demonstrated.
COMPOSITES PART B-ENGINEERING
(2023)
Article
Green & Sustainable Science & Technology
Alejandra S. Escalera Mendoza, D. Todd Griffith, Michael Jeong, Chris Qin, Eric Loth, Mandar Phadnis, Lucy Pao, Michael S. Selig
Summary: The development of large-scale wind turbines faces challenges in terms of loads, mass, and cost growth, as well as the impact of more flexible blades on power and tower clearance. This study proposes an aero-structural rapid screening (ASRS) design approach that utilizes optimization techniques and detailed models to provide fast aerodynamic, structural, and economic results. By introducing blade deflection as a design variable, load-aligned designs can be achieved, maximizing energy capture and minimizing turbine mass.
Article
Engineering, Aerospace
Faraz Ahsan, D. Todd Griffith
Summary: The three key assumptions of Theodorsen's theory were revisited and combined to obtain new lift and moment equations for flutter calculations of full-scale VAWT rotors. The effects of modifying these assumptions were studied for three primary flutter modes, with significant changes observed for the propeller mode.
Article
Green & Sustainable Science & Technology
Meghan Kaminski, Juliet Simpson, Eric Loth, Lee Jay Fingersh, Andy Scholbrock, Nick Johnson, Kathryn Johnson, Lucy Pao, Todd Griffith
Summary: Operational experimental testing results for a 44.5 m diameter wind turbine rotor were obtained, and it was found that the sub-scale model reasonably represents the dynamics of the full-scale rotor, demonstrating the potential of low-cost high-fidelity sub-scale testing for novel extreme-scale turbine designs.
Article
Green & Sustainable Science & Technology
Mayank Chetan, Shulong Yao, D. Todd Griffith
Summary: With advancements in technology, the wind energy industry has been able to produce larger wind turbine rotor blades. However, these larger blades are prone to aeroelastic instabilities. This research evaluates the flutter behavior of two-bladed, downwind rotors and presents a solution to mitigate flutter in the structural design process.
WIND ENERGY SCIENCE
(2022)
Article
Green & Sustainable Science & Technology
Mohammad Sadman Sakib, D. Todd Griffith
Summary: A good understanding of aerodynamic loading is crucial in the design of vertical-axis wind turbines. This study comprehensively analyzes the effect of different design variables on the aerodynamic loads, including the number of blades, aspect ratio, and blade tapering. The study also highlights the importance of considering parked loads and lateral loads during turbine operation.
WIND ENERGY SCIENCE
(2022)
