Impact of the blade shape distortion due to manufacture on the turbine loads and energy yield

Malo Rosemeier, Matthias Saathoff
2020 Zenodo  
A blade shape distortion develops during the manufacturing process. The distortion is referred to as difference between the target blade shape as per design and the shape under operational temperatures. This initial distortion varies under operational temperatures due to different thermal coefficients of expansion of the various blade materials. This resulting distortion due to manufacture and operational temperatures affects the twist angle, the cross-sectional shape and the sweep of the
more » ... sweep of the blade. Young's modulus of the blade's raw materials, i.e., the matrix of the fiber reinforced polymers and the adhesive material, changes during the manufacturing process, complicating the determination of the distortion. To this end, the shape distortion was calculated for a reference temperature on the basis of a thermal stress analysis using a full 3D finite element blade model. An aero-elastic load simulation was conducted for two models: one with the target blade shape and one with the distorted shape. The simulation revealed that the turbine with the distorted shape had a loss of 0.5% in energy yield. A pitch angle offset slightly decreased the loss to 0.4%.
doi:10.5281/zenodo.3803079 fatcat:r5ox3azd3feifpbsclixkincuq