evoblade, a spin-off of the Institute of Aerospace Technology (IAT) of the University of Applied Sciences Bremen, has developed a retrofittable spoiler for rotor blades with the help of Deutsche Windtechnik and Wirtschaftsförderung Bremen. The EvoFlap can be adapted to different rotor blade types. The NEG Micon NM 82 turbine type with a rated output of 1.5 MW and a rotor blade length of 40 m was selected as the basic system for the optimisation. The flow element was developed using the GFRP sandwich technique and has an overall length of 10 m. It is divided into seven segments to allow assembly directly on an installed rotor blade. The blade does not have to be removed from the hub to allow EvoFlap to be installed
The results of a side-by-side study (project duration 08/2015 - 03/2019) confirmed the increase in AEP (annual energy production) that had been predicted using simulated data. Recent results also show a six percent increase in AEP with an average annual wind speed of 7 m/s. In addition to increasing the yield, it was demonstrated that the EvoFlap also increases the bending and torsion strength of the rotor blade.
The EvoFlap can theoretically be installed on all wind turbines that have a slender design in the area of the blade root. The flow element is suitable as a retrofit solution or for manufacturers of wind turbines, but it needs to be adapted to the individual characteristics of the corresponding blade type.
