Wind tunnel experiments on wind turbine wakes in yaw:
Redefining the wake width

Schottler, Jannik; Bartl, Jan; Mühle, Franz; Sætran, Lars Roar; Peinke, Joachim; Hölling, Michael

doi:10.5194/wes-2017-58

Cited by 12 publications

(20 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In this section, the blade loading of the wind turbine used by Krogstad and Adaramola, Mühle et al, Bartl et al, and Schottler et al is validated for different operating conditions and yaw angles. Further, the azimuthal variation of the blade loading as a function of tip‐speed ratio is discussed with the aim to understand its implication for the wake development.…”

Section: Blade Loadingmentioning

confidence: 99%

Parametric dependencies of the yawed wind‐turbine wake development

2020

View full text Add to dashboard Cite

Yaw misalignment is currently being treated as one of the most promising methods for optimizing the power of wind farms. Therefore, detailed knowledge of the impact of yaw on the wake development is necessary for a range of operating conditions. This study numerically investigates the wake development behind a single yawed wind turbine operating at different tip-speed ratios and yaw angles using the actuator-line method in the spectral-element code Nek5000. It is shown that depending on the tip-speed ratio, the blade loading varies along the azimuth, resulting in a wake that is asymmetric in both the horizontal and vertical directions. Large tip-speed ratios as well as large yaw angles are shown to decrease the vertical asymmetry of the yaw-induced counter-rotating vortex pair. Both parameters have the effect that they increase the spanwise force induced by yaw relative to the wake rotation. However, while the strength of the counter-rotating vortex pair in the far wake increases with yaw angle, it is shown to decrease with the tip-speed ratio. The vertical shift in the wake center is found to be highly dependent on the yaw angle and the tip-speed ratio. These detailed insights into the yawed wake are important when optimizing potential downstream turbines. KEYWORDS actuator-line method, CFD, spectral-element method, wake breakdown, wind turbine, yaw

show abstract

Section: Blade Loadingmentioning

confidence: 99%

Parametric dependencies of the yawed wind‐turbine wake development

2020

View full text Add to dashboard Cite

show abstract

“…Wake models are often based on LES studies [11, 27, 31, 34, 58–61], wind tunnel experiments [8–10, 12, 31, 59, 61, 62] or on measurement data from utility‐scale turbines [63–65] to derive simplified analytical models. The most important characteristics of interest are the contour of the wake field, velocity deficit, yaw behaviour, turbulence increase, vortices and meandering [11, 24, 31, 34, 61, 66, 67].…”

Section: Review On Tools and Models For Wf Simulation Frameworkmentioning

confidence: 99%

“…The wake-surrounding interaction increases at higher turbulences, leading to less distinct wakes [8]. (4) An important qualitative property is the deflection of the wake centre line in lateral direction if the WT is yawed [9][10][11][12].…”

Section: Requirements On Wt Aerodynamicsmentioning

confidence: 99%

Analytical three‐dimensional wind flow model for real‐time wind farm simulation

Kipke

Chhor

2020

IET Renewable Power Generation

View full text Add to dashboard Cite

“…Some studies on the effects of yaw misalignment on wind turbine wakes have already been carried out in wind tunnel conditions describing the effect of WT yaw on the wake position (e.g. Bastankhah and Porté-Agel (2016); Grant et al (1997); Howland et al (2016); Schottler et al (2018)), but without studying the transient process between the non-yawed and yawed conditions. However, analyzing yaw manoeuvre dynamics affords new insights into wake interactions.…”

Section: Introductionmentioning

confidence: 99%

Experimental investigation of wind turbine wake and load dynamics during yaw manoeuvres

Macrí¹,

Aubrun²,

Leroy³

et al. 2020

Preprint

View full text Add to dashboard Cite

Abstract. This paper investigates the effect of yawing a wind turbine on its wake deviation dynamics and on the global load variation of a downstream wind turbine during a positive and negative yaw manoeuvre, representing a misalignment/realignment scenario. Yaw manoeuvres could be used to voluntarily misalign wind turbines when wake steering control is targeted. The aim of this wind farm control strategy, which is increasingly studied, is to optimize the overall production of the wind farm and possibly its lifetime, by mitigating wake interactions. Whereas wake flow and wind turbine load dynamics during yaw manoeuvres are usually approached by quasi-static models, the present study aims at quantifying dynamical properties of these phenomena. Wind tunnel experiments were conducted in three different configurations, varying both scaling and flow conditions, in which the yaw manoeuvre was reproduced in a homogeneous turbulent flow at two different scales, and in a more realistic flow such as a modelled atmospheric boundary layer. The effects of yaw control on the wake deviation were investigated by the use of stereo Particle Imaging Velocimetry while the load variation on a downstream wind turbine was measured through an unsteady aerodynamic load balance. While overall results show a non dependence of the wake and load dynamics on the flow conditions and Reynolds scales, they highlight an influence of the yaw manoeuvre direction on their temporal dynamics.

show abstract

Wind tunnel experiments on wind turbine wakes in yaw: Redefining the wake width

Cited by 12 publications

References 35 publications

Parametric dependencies of the yawed wind‐turbine wake development

Parametric dependencies of the yawed wind‐turbine wake development

Analytical three‐dimensional wind flow model for real‐time wind farm simulation

Experimental investigation of wind turbine wake and load dynamics during yaw manoeuvres

Contact Info

Product

Resources

About