Load validation and comparison versus certification approaches of the Riso Dynamic Wake Meandering model implementation in GH Bladed

摘要

The present paper outlines the Riso Dynamic Wake Meandering model (OWM) [1], that has been improved within the EU research project TOPFARM, its implementation into the wind turbine load calculation software GH Bladed and the subsequent load validation. The new Bladed DWM module is compared against two measurement campaigns. The first validation, against data from the EU project Dynamic Loads in Wind Farms [12], indicated quantitatively good agreements for blade root flapwise bending moment and yaw torsion. The second campaign referred to measurements from the Homs Rev offshore wind farm. The related validation indicated quantitatively good agreement for the blade root flapwise bending moment and the tower base overturning moment in the operational region below and above rated power. Discrepancies between measurement and simulation in the wake affected tower base overturning moment around rated power are deemed to be caused by free flow load differences, not by the wake model. A fatigue load comparison of the Bladed DWM model with the commonly used effective turbulence intensity approach from the IEC 61400-1 Standard was performed. The result suggested that the IEC approach is conservative at low turbine spacings but may under predict wake toads for spacings larger than 5 rotor diameters (D).