Smart Blades (Task 2.1.5)
„Research of the near-rotor turbulent wind inflow“ Task 2.1.5 in the Project „Smart Blades - Development and design of intelligent rotor blades“ (FKZ 0325601D)
ForWind – Center for wind energy research, Carl von Ossietzky University Oldenburg
Duration of the project:
12/2012 – 02/2016
- Which local turbulence structures are expected to occur in the near-rotor inflow?
- Which effects do these local turbulence structures have on the rotor?
- Which retroactive effect does the rotor have on the turbulent wind structures?
The loads on rotor blades of wind turbines are defined most significantly by the turbulent wind inflow. As a result, up to 10^8 load cycles are expected to take place during the 20-year long operational life time of a wind turbine. Until now, the possibilities of research on the precise temporal and spatial structure of turbulent near-rotor inflow were limited. Current measurement methods are restricted to point measurements, e.g. with cup anemometers or relatively slow scanning rates (5-20 Hz) with pulsed LiDAR systems.
Measurements in alpha ventus
In the frame of the Smart Blades project, which is funded by the Federal Ministery for Economic Affairs and Energy, a so-called „short-range WindScanner“ will be acquired, which will be mounted on a wind turbine in a wind farm in the scope of the RAVE project. With this system, it is possible to scan up to 400 measurement points per second at a focus distance of 200 m on a conical measurement surface. The spatial resolution in the line-of-sight direction is – depending on the focus distance – clearly smaller than that of currently used devices, whereas the temporal resolution is 10-40 times larger.
The short-range WindScanner will be operated for about six months either in the spinner or on the nacelle of a wind turbine. The goals of the measurement campaign are:
- Derivation of turbulence characteristics and wind field properties in the rotor blockage region for the preparation of aerodynamic and aeroelastic analysis
- Correlation of the measured turbulent wind flow with local wind turbine loads for validation of aeroelastic models
- Preparation of reference data for the specification of simple, robust laser-optic systems for predictive control methods
ForWind – Center for wind energy research
Carl von Ossietzky University of Oldenburg
Ammerländer Heerstr. 126
Tel. (0441) 798 5060
Research Group Wind Energy Systems, Prof. Dr. Martin Kühn