Developing a passive load reduction blade for the DTU 10 MW reference turbine

The Science of Making Torque from Wind

De Vaal, J.B.^1 ; Nygaard, T.A.^1 ; Stenbro, R.^1

Institute for Energy Technology (IFE), Kjeller, Norway^1

关键词: Annual energy productions;    Blade deflection;    Elastic analysis;    Equivalent fatigue damage;    Load alleviating;    Out-of-plane bending;    Steady state loads;    Torsional deformations;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/753/4/042004/pdf
DOI  :  10.1088/1742-6596/753/4/042004

来源: IOP

【 摘 要 】

This paper presents the development of a passive load reduction blade for the DTU 10 MW reference wind turbine, using the aero-hydro-servo-elastic analysis tool 3DFloat. Passive load reduction is achieved by introducing sweep to the path of the blade elastic axis, so that out-of-plane bending deflections result in load alleviating torsional deformations of the blade. Swept blades are designed to yield similar annual energy production as a rotor with a reference straight blade. This is achieved by modifying the aerodynamic twist distribution for swept blades based on non-linear blade deflection under steady state loads. The passive load reduction capability of a blade design is evaluated by running a selection of fatigue- and extreme load cases with the analysis tool 3DFloat and determining equivalent fatigue loads, fatigue damage and extreme loads at the blade root and tower base. The influence of sweep on the flutter speed of a blade design is also investigated. A large number of blade designs are evaluated by varying the parameters defining the sweep path of a blade's elastic axis. Results show that a moderate amount of sweep can effectively reduce equivalent fatigue damage and extreme loads, without significantly reducing the flutter speed, or compromising annual energy production.