Influence of atmospheric stability on wind turbine loads

Sathe, Ameya; Mann, Jakob; Barlas, Thanasis K.; Bierbooms, W.A.A.M.; Bussel, G.J.W. Van

doi:10.1002/we.1528

Cited by 155 publications

(136 citation statements)

References 42 publications

(69 reference statements)

Supporting

Mentioning

127

Contrasting

Order By: Relevance

“…Gryning et al (2007) found that for a two-year period, easterly surface winds agreed well with the observations using the ψ m expressions of Dyer (1974). Similarly, Peña (2009) and Sathe et al (2013) found that commonly used expressions for ψ m suited the easterly surface wind profile for a range of stability classes based on four years of data. These works show that the diabatic wind profile is accurate in describing the vertical wind shear up to a height that depends on the stability of the surface layer, for very unstable and stable conditions up to 160 and 40 m, respectively.…”

Section: Surface Layermentioning

confidence: 62%

“…These results demonstrate the close connection between the wind profile and the turbulence structure. Sathe et al (2013) re-derived the Mann model parameters to estimate the impact of turbulence under different stabilities on turbine loads. By including stability effects, they found that the loads on a number of turbine components increased up to 17% compared to the neutral case.…”

Section: Traditional Anemometry-based Studiesmentioning

confidence: 99%

See 1 more Smart Citation

Ten Years of Boundary-Layer and Wind-Power Meteorology at Høvsøre, Denmark

Peña

Floors

Sathe

et al. 2015

Boundary-Layer Meteorol

101

103

View full text Add to dashboard Cite

Operational since 2004, the National Centre for Wind Turbines at Høvsøre, Denmark has become a reference research site for wind-power meteorology. In this study, we review the site, its instrumentation, observations, and main research programs. The programs comprise activities on, inter alia, remote sensing, where measurements from lidars have been compared extensively with those from traditional instrumentation on masts. In addition, with regard to wind-power meteorology, wind-resource methodologies for wind climate extrapolation have been evaluated and improved. Further, special attention has been given to research on boundary-layer flow, where parametrizations of the length scale and wind profile have been developed and evaluated. Atmospheric turbulence studies are continuously conducted at Høvsøre, where spectral tensor models have been evaluated and extended to account for atmospheric stability, and experiments using microscale and mesoscale numerical modelling.

show abstract

Section: Surface Layermentioning

confidence: 62%

Section: Traditional Anemometry-based Studiesmentioning

confidence: 99%

Ten Years of Boundary-Layer and Wind-Power Meteorology at Høvsøre, Denmark

Peña

Floors

Sathe

et al. 2015

Boundary-Layer Meteorol

101

103

View full text Add to dashboard Cite

show abstract

“…In a following study, Kelley (2011) detected that the maximum turbine damages occurred within a narrow range of atmospheric stability usually associated with LLJs. Sathe et al (2013) used wind profile models together with an aeroelastic simulator to investigate whether the wind profile and the atmospheric stability modify the wind turbine loads. They found that loads at different turbine parts were affected slightly by the wind profile (up to 7 %) and significantly by the atmospheric stability (up to 17 %).…”

Section: Previous Work On Wind Shearmentioning

confidence: 99%

Impacts of the low-level jet's negative wind shear on the wind turbine

et al. 2017

View full text Add to dashboard Cite

Abstract.Nocturnal low-level jets (LLJs) are defined as relative maxima in the vertical profile of the horizontal wind speed at the top of the stable boundary layer. Such peaks constitute major power resources for wind turbines. However, a wind speed maximum implies a transition from positive wind shears below the peak to negative ones above. The effect that such a transition has on wind turbines has not been thoroughly studied.This research study employed a methodical approach to the study of negative wind shear's impacts on wind turbines. Up to now, the presence of negative shears inside the turbine's rotor in relation to the presence of positive shears has been largely ignored. A parameter has been proposed to quantify that presence in future studies of LLJ-wind-turbine interactions. Simulations were performed using the NREL aeroelastic simulator FAST code. Rather than using synthetic profiles to generate the wind data, all simulations were based on real data captured at the high frequency of 50 Hz, which allowed us to perform the analysis of a turbine's impacts with real-life, small scales of wind motions.It was found that the presence of negative wind shears at the height of the turbine's rotor appeared to exert a positive impact on reducing the motions of the nacelle and the tower in every direction, with oscillations reaching a minimum when negative shears covered the turbine swept area completely. Only the tower wobbling in the spanwise direction was amplified by the negative shears; however, this occurred at the tower's slower velocities and accelerations. The forces and moments were also reduced by the negative shears. The aforementioned impacts were less beneficial in the rotating parts, such as the blades and the shafts. Finally, the variance in power production was also reduced. These findings can be very important for the next generation of wind turbines as they reach deeper into LLJ's typical heights.The study demonstrated that the presence of negative shears is significant in reducing the loading on wind turbines. A major conclusion of this study is that the wind turbines of the future should probably be designed with the aim of reaching the top of the nightly boundary layer more often and therefore the altitudes where negative shears are more frequent. Doing so will help to reduce the positive shear's associated damage and to capture the significant LLJ energy.

show abstract

“…Most of wind projects are developed based on the mean wind speed at the hub height of the turbine without any consideration of atmospheric stability effect. However, significant dependence of wind resource on this stability issue has been recognized [1,2]. Stability is linked to the influence of the thermal effects.…”

Section: Introductionmentioning

confidence: 99%

Effect of atmospheric stability on the estimation of wind power potentiaEffect potential

2016

View full text Add to dashboard Cite

Abstract. Analyzing the impact of atmospheric stability on vertical wind profile enables to assess the available wind resource in order to determine optimal locations for wind turbines. Different methods have been proposed to study the degree of stability of the atmosphere. These include the Richardson number, the profile method and the Monin-Obukhov length. Focus is here on the stability issue and its influence on the wind shear coefficient which plays an important role in processing experimental data with regards to the atmospheric surface-layer turbulence. Data collected from the Cabauw meteorological mast were analyzed in order to determine the characteristics of the wind resource at that location and to estimate the wind resource for power determine the characteristics of the wind resource at that location and to estimate the wind resource for power generation as affected by stability.

show abstract

Influence of atmospheric stability on wind turbine loads

Cited by 155 publications

References 42 publications

Ten Years of Boundary-Layer and Wind-Power Meteorology at Høvsøre, Denmark

Ten Years of Boundary-Layer and Wind-Power Meteorology at Høvsøre, Denmark

Impacts of the low-level jet's negative wind shear on the wind turbine

Effect of atmospheric stability on the estimation of wind power potentiaEffect potential

Contact Info

Product

Resources

About