Study on the aerodynamic damping for the seismic analysis of wind turbines in operation

Meng, Jiayao; Dai, Kaoshan; Zhao, Zhongyuan; Mao, Zhenxi; Cámara, Alfredo; Zhang, Songhan; Mei, Zhu

doi:10.1016/j.renene.2020.05.181

Cited by 30 publications

(5 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The aerodynamic damping depends on many factors, such as the wind and rotational speeds, the geometrical configuration of the blade, the derivative of the lift coefficient to the angle of attack, and so on. 60 The aerodynamic force of the rotor is normally calculated using the blade element momentum (BEM) method and can be divided into two linearized parts 61 to explicitly investigate the aerodynamic damping. One is independent of the tower vibration velocity and can be estimated with a rigid tower assumption.…”

Section: Fe Modeling Of Owtmentioning

confidence: 99%

“…More specifically, it is an effect that the vibrating velocity of the tower top in the wind direction induces variations in the relative wind speed acting on the rotor and thus changes the attack angle and instantaneous lift and drag forces. The aerodynamic damping depends on many factors, such as the wind and rotational speeds, the geometrical configuration of the blade, the derivative of the lift coefficient to the angle of attack, and so on 60 . The aerodynamic force of the rotor is normally calculated using the blade element momentum (BEM) method and can be divided into two linearized parts 61 to explicitly investigate the aerodynamic damping.…”

Section: Numerical Modelingmentioning

confidence: 99%

See 1 more Smart Citation

Wind‐ and sea wave‐induced response mitigations of offshore wind turbines using track nonlinear energy sinks

Zuo

Zhang

Yuan

et al. 2022

Structural Contr & Hlth

View full text Add to dashboard Cite

Summary Modern offshore wind turbines (OWTs) are constructed with increasingly long blades and slender towers to capture wind resources more effectively. Consequently, OWTs have become vulnerable to wind and sea wave excitations. Mitigations of unfavorable OWT vibrations have been extensively investigated, with the majority focusing on passive vibration control strategies with control performance sensitive to structural frequency changes. Nonlinear energy sinks (NESs) are regarded as effective vibration control methods because their broadband fashion is robust against variations in structural frequencies. A novel NES with an improved track profile that combines both second‐ and fourth‐order polynomials (Track II NES) is proposed in the present study to improve the vibration mitigation effectiveness of traditional Track I NES with a track profile of a fourth‐order polynomial only. Governing equations of a single‐degree‐of‐freedom system with Track II NES are first established, and an equivalent linearization method is adopted to optimize the track profile and damping of the Track II NES. Moreover, a detailed 3D finite element model of a representative 5‐MW OWT is developed. Control effectiveness of the Track II NES is examined under different structural stiffnesses and mean wind speeds and then compared with that of conventional tuned mass damper (TMD) and Track I NES. Numerical results showed that the Track II NES can effectively suppress displacement and acceleration responses of OWTs and outperform its counterpart Track I NES. Moreover, the Track II NES can obtain reduction ratios close to those of the TMD but with better robustness against the detuning effect.

show abstract

Section: Fe Modeling Of Owtmentioning

confidence: 99%

Section: Numerical Modelingmentioning

confidence: 99%

Wind‐ and sea wave‐induced response mitigations of offshore wind turbines using track nonlinear energy sinks

Zuo

Zhang

Yuan

et al. 2022

Structural Contr & Hlth

View full text Add to dashboard Cite

show abstract

“…For instance, Fontecha et al [20] investigated the aerodynamic damping of wind turbines using the artificial excitation method via wind tunnel tests. Meng et al [21] designed a 1/100 scaled-down wind turbine model and identified its aerodynamic damping. However, the above studies are relatively simple as only the aerodynamic damping in the FA direction was investigated.…”

Section: Introductionmentioning

confidence: 99%

Wind-tunnel experimental study on identification of modal aerodynamic damping matrix for operating wind turbines

Wang,

Chen,

Hua

2024

J. Phys.: Conf. Ser.

View full text Add to dashboard Cite

This study aimed to design a scaled wind turbine model, with a geometric scaling factor of 1/75 and based on the NREL-5MW wind turbine prototype, in order to conduct an experimental study on the aerodynamic damping identification under the operating condition. First, the dynamic characteristics of the scaled model such as natural frequency and damping ratio were tested under the parked condition. Then, wind tunnel force measurements were conducted to verify the similarity between the rotor thrust coefficients of the scaled model and prototype, ensuring a reasonable rotor design. Subsequently, identification of the modal aerodynamic damping matrix of the operating scaled wind turbine model was performed using the identification method based on artificial harmonic excitations and frequency response functions. Experimental results show that both the identified diagonal and off-diagonal terms in the modal damping matrix agree well with the theoretical values when the rotor rotation speed is 150 rpm. However, apparent differences between the identified values and theoretical values can be observed when the rotor rotation speed and wind speed change. Generally, the wind tunnel test confirms the availability of the theoretical modal damping matrix expression in capturing the damping characteristics and the feasibility of the identification method for operating wind turbines.

show abstract

“…Therefore, many studies have been performed in the last years focusing on quantifying the effects of wind loads on the dynamic behaviour such as vibrations of tower and tail of small-scale HAWTs. The effect of static and dynamic wind loads has been investigated through experimental measurements and numerical analysis [5][6][7][8]. Other studies have focused on the effect of wind turbulence intensity on the fatigue load and dynamic response for small and large wind turbines [9][10][11].…”

Section: Introductionmentioning

confidence: 99%

Experimental and Numerical Investigation of the Effect of Blades Number on the Dynamic Response of a Small Horizontal-Axis Wind Turbine

et al. 2022

View full text Add to dashboard Cite

The new energy scenario is rising a strong interest towards the distributed production from renewable sources; among them, wind seems to be one of the most interesting and at the same time critical due to the challenges of the conversion technology. Operation of small wind energy conversion systems is generally very complex due the extremely variable regime of operation and the high turbulent wind, so that a deep knowledge of the dynamic response of such devices is crucial not only for optimising their performances but also to make them comfortable to be used in residential areas. For these reasons, the present work is focused on analysing the effect in changing the number of blades on a small horizontal axis wind turbine through an experimental campaign in the wind tunnel. The turbine dynamics has been characterised running some “wind ramp” tests and analysing the rotor capability in following the wind as well the vibrations transmitted by the turbine during the operation. Results demonstrate that a higher number of blades, despite a small decrease of performance, can make the machine more efficient in operating at low wind regimes. At the same time, a higher number of blades can make the rotor efficient even at lower speed of rotation, thus limiting the risks of having high magnitude vibrations.

show abstract

Study on the aerodynamic damping for the seismic analysis of wind turbines in operation

Cited by 30 publications

References 41 publications

Wind‐ and sea wave‐induced response mitigations of offshore wind turbines using track nonlinear energy sinks

Wind‐ and sea wave‐induced response mitigations of offshore wind turbines using track nonlinear energy sinks

Wind-tunnel experimental study on identification of modal aerodynamic damping matrix for operating wind turbines

Experimental and Numerical Investigation of the Effect of Blades Number on the Dynamic Response of a Small Horizontal-Axis Wind Turbine

Contact Info

Product

Resources

About