Prediction of the unsteady aerodynamic characteristics of horizontal axis wind turbines including three-dimensional effects

Abstract Wind turbines can create turbulence and downstream wakes which can introduce generation losses of downstream impacted turbines. These downstream turbine-induced losses are due to two different conditions. The first is from power-producing rotating blades of upstream wind turbines agitating the subsequent downstream wind in a cork-screw like manner. The second is from non-rotating, non-operational, non-power-generating wind turbines. These non-operating turbines may be under scheduled service shutdown, or rendered non-functional due to longer-term or permanent mechanical problems. In this work CFD was used to study downstream turbulence and wakes of a utility-scale, non-operational three-blade horizontal axis wind turbines (HAWT). A flow field was constructed using an unstructured grid around a HAWT (rotor hub elevation of 80 meters and a blade length of 40 meters). Various wind velocities were studied up to 25 meters per second. Incompressible flow was used to assess downstream turbulence using a three-dimensional steady state and unsteady state SST k-ω (two equation) turbulence model. Different blade positions with respect to angle of attack (α) were studied, with a 4 degree angle of attack reported here. Pressures and velocities for distances of 100 meters in front and 500 meters downstream from the wind turbine are reported.

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Validation of a Dynamic Prescribed Vortex Wake Model for Horizontal Axis Wind Turbines

Volume 2: Fora, Parts A and B ◽

10.1115/fedsm2007-37523 ◽

2007 ◽

Author(s):

Hugh D. Currin ◽

Frank N. Coton

Keyword(s):

Structural Dynamics ◽

Wind Turbines ◽

Horizontal Axis ◽

Vortex Wake ◽

Dynamic Flow ◽

Unsteady Aerodynamic ◽

Horizontal Axis Wind Turbines ◽

Aerodynamic Experiment ◽

Wake Model

A new aerodynamic wake model for Horizontal Axis Wind Turbines has been developed. The prescribed vortex wake code HAWTDAWG has been extended to dynamic flow and incorporated into AeroDyn. Linkage to the FAST structural dynamics code is retained. Static and dynamic yawed flow validation is done against Unsteady Aerodynamic Experiment Phase VI data as well as against existing code results.

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Effect of Wind Shear to Horizontal Axis Wind Turbine Aerodynamic

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.521.99 ◽

2014 ◽

Vol 521 ◽

pp. 99-103

Author(s):

Ling Zhang ◽

Hui Xia Sheng ◽

Da Fei Guo

Keyword(s):

Wind Turbine ◽

Wind Turbines ◽

Wind Shear ◽

Numerical Study ◽

Three Dimensional ◽

Horizontal Axis ◽

Power Calculation ◽

Horizontal Axis Wind Turbine ◽

Horizontal Axis Wind Turbines ◽

And Performance

A three-dimensional unsteady numerical study of the streaming flow field of the1.2 MW horizontal axis wind turbines which operation in the 11.26 m/s under the uniform wind and the shear wind have been carried out in this paper. according to the simulation results to understand the effect of uniform flow and the dynamic wind shear flow to the output power of wind turbine and the aerodynamics. results showed that: Under the uniform wind,Wind turbine power calculation values are in good agreement with the design value ,Wind turbines under the influence of wind shear can lead to change in load and performance on the surface of the blade.

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Computational Aerodynamic Analysis of Offshore Upwind and Downwind Turbines

Journal of Aerodynamics ◽

10.1155/2014/860637 ◽

2014 ◽

Vol 2014 ◽

pp. 1-13 ◽

Cited By ~ 11

Author(s):

Qiuying Zhao ◽

Chunhua Sheng ◽

Abdollah Afjeh

Keyword(s):

Wind Turbine ◽

Wind Turbines ◽

Computational Analysis ◽

Bending Moment ◽

Horizontal Axis ◽

Aerodynamic Loads ◽

Unsteady Aerodynamic ◽

Horizontal Axis Wind Turbines ◽

Computational Fluid Dynamics Cfd ◽

Insight Into

Aerodynamic interactions of the model NREL 5 MW offshore horizontal axis wind turbines (HAWT) are investigated using a high-fidelity computational fluid dynamics (CFD) analysis. Four wind turbine configurations are considered; three-bladed upwind and downwind and two-bladed upwind and downwind configurations, which operate at two different rotor speeds of 12.1 and 16 RPM. In the present study, both steady and unsteady aerodynamic loads, such as the rotor torque, blade hub bending moment, and base the tower bending moment of the tower, are evaluated in detail to provide overall assessment of different wind turbine configurations. Aerodynamic interactions between the rotor and tower are analyzed, including the rotor wake development downstream. The computational analysis provides insight into aerodynamic performance of the upwind and downwind, two- and three-bladed horizontal axis wind turbines.

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