Effect of Geometric Uncertainties on the Aerodynamic Characteristic of Offshore Wind Turbine Blades

The Science of Making Torque from Wind 2012

Ernst, Benedikt^1 ; Schmitt, Henning^1 ; Seume, Jörg R.^1

ForWind-Center for Wind Energy Research, Leibniz Universität Hannover, Institute of Turbomachinery and Fluid Dynamics-TFD, Appelstr. 9, Hannover

30167, Germany^1

关键词: Aerodynamic characteristics;    Annual energy productions;    Geometric uncertainties;    Latin hypercube sampling;    Lift and drag coefficients;    Manufacturing tolerances;    Reliability and safeties;    Unsteady aerodynamic load;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/555/1/012033/pdf
DOI  :  10.1088/1742-6596/555/1/012033

来源: IOP

【 摘 要 】

Offshore wind turbines operate in a complex unsteady flow environment which causes unsteady aerodynamic loads. The unsteady flow environment is characterized by a high degree of uncertainty. In addition, geometry variations and material imperfections also cause uncertainties in the design process. Probabilistic design methods consider these uncertainties in order to reach acceptable reliability and safety levels for offshore wind turbines. Variations of the rotor blade geometry influence the aerodynamic loads which also affect the reliability of other wind turbine components. Therefore, the present paper is dealing with geometric uncertainties of the rotor blades. These can arise from manufacturing tolerances and operational wear of the blades. First, the effect of geometry variations of wind turbine airfoils on the lift and drag coefficients are investigated using a Latin hypercube sampling. Then, the resulting effects on the performance and the blade loads of an offshore wind turbine are analyzed. The variations of the airfoil geometry lead to a significant scatter of the lift and drag coefficients which also affects the damage-equivalent flapwise bending moments. In contrast to that, the effects on the power and the annual energy production are almost negligible with regard to the assumptions made.