Article
Thermodynamics
Yuan Fang, Gen Li, Lei Duan, Zhaolong Han, Yongsheng Zhao
Summary: This study investigates the aerodynamics of FHAWT's rotor and its wake characteristics under surge motion, revealing that surge motion significantly impacts the aerodynamics of the rotor and wake characteristics of FHAWT, especially affecting thrust, torque, and rotor power.
Article
Thermodynamics
Chong Sun, Tian Tian, Xiaocheng Zhu, Ouyang Hua, Zhaohui Du
Summary: The wake flow of a horizontal-axis wind turbine has a significant impact on energy extraction and downstream turbulent flow. Large eddy simulation is used to investigate the flow dynamics over a two-blade wind turbine model, with dynamic mode decomposition revealing the dominant features of the wake flow and their effects on energy extraction.
Article
Thermodynamics
Guang Chen, Xi-Feng Liang, Xiao-Bai Li
Summary: This study uses numerical simulation to investigate the impact of platform surge motion on the aerodynamic performance and wake instabilities of wind turbines. The results show that surge motion can enhance power generation efficiency, promote wake instabilities and vortex interactions, and have a positive effect on wake recovery.
Article
Green & Sustainable Science & Technology
Luca Greco, Claudio Testa
Summary: This study investigates the performance of a horizontal axis wind turbine in axial and yawed flow using a free-wake, unsteady, three-dimensional aerodynamic formulation. The comparison between numerical predictions and experimental data highlights the applicability and limitations of aerodynamic formulations based on the Boundary Element Method in wind turbine applications. Additionally, the performance of a model-scale rotor in different operating conditions is discussed, providing insights into extreme shear and rotor installation on a floating platform undergoing pitching motion.
Article
Mechanics
Xiaodong Liu, Haiyang Xu, Bohan Wang, Yuankui Wang, Chenglong Li, Yulin Si, Peng Qian, Dahai Zhang
Summary: This paper investigates the wake characteristic of a ducted turbine using flume experiments and large eddy simulations, proposing an analytical wake model of the ducted turbine and verifying it through different inflow velocities and tandem arrangements. The results show that the wake of a ducted turbine maintains a high self-similarity and approximately follows a double-Gaussian curve. Compared with a conventional tidal turbine, a ducted turbine has a faster wake recovery speed but a larger radial influence range, indicating the need for wider radial distances and shorter axial distances in ducted turbine arrays.
Article
Thermodynamics
Xiaocheng Zhu, Chong Sun, Hua Ouyang, Zhaohui Du
Summary: In this study, the impact of the nacelle and tower on the near wake of a small-scale horizontal-axis wind turbine was investigated using large eddy simulation and dynamic mode decomposition. The presence of the nacelle and tower was found to directly affect the high-speed rotating vortices, leading to the breakdown of tip vortices and earlier wake recovery.
Article
Engineering, Marine
Muyu Zhao, Ying Chen, Jin Jiang
Summary: This study investigates the effect of roll motion on the performance of a floating double-rotor horizontal axis tidal current turbine using Computational Fluid Dynamics (CFD) method. The results show that roll motion leads to a maximum decrease of 30.76% in the average power coefficient and introduces fluctuations in the instantaneous load. Additionally, roll motion significantly accelerates the recovery of wake velocity, with different combinations of roll periods and tip speed ratios resulting in varying degrees of wake velocity recovery.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2023)
Article
Engineering, Civil
Wonsuk Han, Homin Kim, Eunkuk Son, Soogab Lee
Summary: This study investigates the impact of wake steering on wind turbines using the unsteady vortex lattice method (UVLM) and the curled wake model. The results show that the counter-rotating vortices significantly affect the aerodynamics of wind turbines, including the effective angle of attack and wake deflection.
JOURNAL OF WIND ENGINEERING AND INDUSTRIAL AERODYNAMICS
(2023)
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
Green & Sustainable Science & Technology
Daniel Micallef, Abdolrahim Rezaeiha
Summary: Over the past decade, there has been a steady increase in scientific articles on rotor aerodynamics of offshore wind turbines, highlighting the critical role of aerodynamics in overcoming specific barriers in multi-physics systems. Current trends in research focus on the interaction between aerodynamics and other fields, such as platform hydrodynamics and control, with common approaches being coupled or uncoupled studies. The literature mainly addresses isolated floating turbines, while studies on interactions between floating turbines are limited.
RENEWABLE & SUSTAINABLE ENERGY REVIEWS
(2021)
Article
Energy & Fuels
Shalini Verma, Akshoy Ranjan Paul, Anuj Jain
Summary: This study focuses on improving the aerodynamic performance, analysing the turbulence effect, and structural response of the horizontal axis wind turbine (HAWT) blade. Adding a winglet at the blade's tip enhances aerodynamic efficiency and increases power performance. The results indicate that turbulence intensity can significantly affect the overall performance of the wind turbine.
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2022)
Article
Green & Sustainable Science & Technology
Zhiteng Gao, Ye Li, Tongguang Wang, Wenzhong Shen, Xiaobo Zheng, Stefan Probsting, Deshun Li, Rennian Li
Summary: The study introduces a new anisotropic body-force projection model in the actuator line model for wind-turbine wakes, showing that it can predict wakes more accurately and investigate wake characteristics under various yaw conditions. The research demonstrates the significant impact of nacelle effects on wind-turbine wakes, especially during yaw conditions.
Article
Engineering, Marine
Yuming Yuan, Q. W. Ma, Shiqiang Yan, Xing Zheng, Kangping Liao, Gang Ma, Hanbing Sun, Abbas Khayyer
Summary: Predicting the wake of an upwind turbine is crucial for evaluating the performance of downwind turbines in offshore wind farms. This paper proposes a hybrid method that combines a CFD model for simulating the near wake flow and an improved simplified CFD model for modeling the far wake flow. The new method is validated against full CFD simulations and shown to produce similar results in considerably less computational time.
Article
Mechanics
Benjamin Strom, Brian Polagye, Steven L. Brunton
Summary: This study examines the coherent structures in the wake of a single two-bladed cross-flow turbine, including the mean wake structure, unsteady flow, and oscillatory wake component. The study reveals the presence of vortex streets and axial flow in the wake, with significant variation in vortex trajectory.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Thermodynamics
Jiahao Wen, Lei Zhou, Hongfu Zhang
Summary: The blade number of a wind turbine significantly affects its near-wake dynamics. Increasing the blade number leads to an early formation of a single peak velocity distribution in the wake, affects the width and velocity deficit of the wake, and influences the recovery of the wake, energy extraction, and fatigue loads of downstream turbines.
Article
Computer Science, Interdisciplinary Applications
Jacobus D. Brandsen, Axelle Vire, Sergio R. Turteltaub, Gerard J. W. Van Bussel
Summary: This paper evaluates the penalty and Lagrange multiplier methods for enforcing the no-slip condition in fluid-structure interaction simulations. The Lagrange multiplier method provides accurate solutions without parameter tuning, but at a higher computational cost. The penalty method can achieve similar accuracy, but requires selecting the appropriate penalty factor.
ENGINEERING COMPUTATIONS
(2021)
Article
Green & Sustainable Science & Technology
Jing Dong, Axelle Vire
Summary: This study aims to predict the occurrence of the vortex ring state (VRS) during the operation of floating offshore wind turbines, and the results show that VRS may occur for a wide range of operating conditions. The most suitable criterion for VRS prediction is found to be Wolkovitch's criterion.
Article
Energy & Fuels
Maarten T. van Beek, Axelle Vire, Soren J. Andersen
Summary: This paper investigates the potential for improved performance of the Lillgrund wind farm through a detailed calibration of a low-fidelity engineering model aimed specifically at yaw-based wake steering. It shows that the model is overparameterized, but can yield higher energy gains when input uncertainty is taken into account during optimization.
Article
Green & Sustainable Science & Technology
D. De Tavernier, C. Ferreira, A. Vire, B. LeBlanc, S. Bernardy
Summary: The study demonstrates that vortex generators (VGs) can delay or suppress dynamic stall process in unsteady flow conditions, with important factors being VG height and mounting position. Configurations with VGs show a larger loss in normal coefficient when VG effectiveness vanishes, but the flow reattaches quicker and the airfoil recovers easier from deep-stall conditions.
Article
Computer Science, Interdisciplinary Applications
Julia Steiner, Richard P. Dwight, Axelle Vire
Summary: The article introduces a systematic data-driven approach to deriving new Reynolds-Averaged Navier-Stokes (RANS) models in the wind-energy setting, showing significantly improved predictions compared to baseline models. Time-averaged LES data is used as ground-truth to derive optimal corrective fields for turbulence effects, and a custom RANS closure is built using deterministic symbolic regression to improve predictions for mean velocity and turbulence kinetic energy fields.
COMPUTERS & FLUIDS
(2022)
Article
Energy & Fuels
Lu Wang, Amy Robertson, Jason Jonkman, Jang Kim, Zhi-Rong Shen, Arjen Koop, Adria Borras Nadal, Wei Shi, Xinmeng Zeng, Edward Ransley, Scott Brown, Martyn Hann, Pranav Chandramouli, Axelle Vire, Likhitha Ramesh Reddy, Xiang Li, Qing Xiao, Beatriz Mendez Lopez, Guillen Campana Alonso, Sho Oh, Hamid Sarlak, Stefan Netzband, Hyunchul Jang, Kai Yu
Summary: This study investigates the feasibility of using computational fluid dynamics (CFD) simulations to tune mid-fidelity models in floating offshore wind systems. The simulations are validated against experimental results, and reasonable agreement is found between the two. The linear and quadratic damping coefficients have large numerical uncertainties, while the equivalent damping ratios are consistently predicted with lower uncertainty.
Article
Energy & Fuels
Axelle Vire, Geert Lebesque, Mikko Folkersma, Roland Schmehl
Summary: This paper presents steady-state RANS simulations for a leading-edge inflatable (LEI) wing, exploring its aerodynamic performance and local flow characteristics. The results show that side-slip has a negative impact on the wing's aerodynamic performance, while the chordwise struts have little influence.
Article
Green & Sustainable Science & Technology
Jing Dong, Axelle Vire, Zhangrui Li
Summary: This paper conducts a comparative analysis and evaluation of the vortex ring state (VRS) phenomenon and aerodynamic performance of a floating offshore wind turbine (FOWT), and compares the results with other similar studies, providing a deeper understanding of the working state changes of FOWTs.
Article
Thermodynamics
Julia Steiner, Axelle Vire, Richard P. Dwight
Summary: Data-driven RANS turbulence closures are considered a viable option in wind energy. Parsimonious models have advantages in terms of stability, interpretability, and execution speed. Model corrections need to be made only in limited regions, and introducing a classifier helps identify these regions.
FLOW TURBULENCE AND COMBUSTION
(2022)
Article
Green & Sustainable Science & Technology
Jing Dong, Axelle Vire
Summary: This paper investigates the working state changes of the rotor in floating offshore wind turbines with platform motions, and quantitatively and visually evaluates them using an aerodynamic model. The results show that the rotor experiences alternating windmill, vortex ring, and propeller states during a full cycle of the surge motion of the floating platform, with the vortex ring state being the most unstable.
Article
Energy & Fuels
Manuel Rentschler, Pranav Chandramouli, Guilherme Vaz, Axelle Vire, Rodolfo T. Goncalves
Summary: With the advancement of high-performance computation capabilities, high-fidelity modelling tools such as computational fluid dynamics are increasingly used in the offshore renewable sector. This work compares the results of two different CFD codes, OpenFOAM and ReFRESCO, with water tank experiments. The study finds that both codes accurately model the natural period of the decay simulations but are overly dissipative in terms of damping. Differences between the codes are revealed through flow field analysis.
JOURNAL OF OCEAN ENGINEERING AND MARINE ENERGY
(2023)
Article
Engineering, Marine
Hiromasa Otori, Yuka Kikuchi, Irene Rivera-Arreba, Axelle Vire
Summary: The hydrodynamic coefficients are evaluated using fully nonlinear Navier-Stokes forced oscillation simulations with the volume of fluid method. Richardson extrapolation is used to obtain grid-independent solutions. The predicted hydrodynamic coefficients are validated through water tank tests. The drag coefficient models' applicability for a barge-type floater is investigated by comparing with numerically predicted drag coefficients for different Keulegan-Carpenter numbers in the surge and heave directions. Dynamic response analyses are then performed using the engineering model with the validated drag coefficient models. The results show that considering drag forces leads to better agreement with measurements, especially in high wave conditions.
Article
Green & Sustainable Science & Technology
Axelle Vire, Bruce LeBlanc, Julia Steiner, Nando Timmer
Summary: This experimental study focuses on the addition of a passive slat on a thick airfoil typically used in the inboard part of commercial wind turbine blades. The results show that the presence of a slat can increase the lift-to-drag ratio of the airfoil, especially for clean airfoil and small angles of attack.
WIND ENERGY SCIENCE
(2022)
Article
Green & Sustainable Science & Technology
Carlos Ferreira, Wei Yu, Arianna Sala, Axelle Vire
Summary: This study investigates the large surge motions and blade-vortex interaction phenomenon of floating offshore wind turbines. The findings show that the actuator disc momentum theory and the blade element momentum theory are valid and accurate in predicting the induction at the actuator in surge, even for large and fast motions.
WIND ENERGY SCIENCE
(2022)
Article
Green & Sustainable Science & Technology
Axelle Vire, Adriaan Derksen, Mikko Folkersma, Kumayl Sarwar
WIND ENERGY SCIENCE
(2020)
