The SWUF-3D fleet, which is further developed and enabled to measure spatial turbulence structures within the ESTABLIS-UAS project was deployed in March 2025 to measure the near wake flow of wind turbines in the WiValdi research park.
The measurement strategy included measurements with 10 drones in three distances to the wind turbine, as close as 0.5 rotor diameters downstream. A special interest is in the decay of tip vortices and the impact on wake turbulence development.
The challenges of the campaign included the correct detection of wind direction and wind turbine yaw, relatively low wind speeds over a long period and wind turbine downtime due to maintenance, failures and power curtailment. We learned a lot sitting under a wind turbine for 2.5 weeks!
In times without wake-conditions, we used the time to perform general boundary-layer turbulence measurements. Some key achievements were:
– Direct comparison of different UAS setups for wind and turbulence measurements against the WiValdi met mast array.
– Reaching flight times over 60 minutes with our newest type of drones in a fleet configuration for the first time.
– Strong wind turbulence measurements with gusts exceeding 20 m/s.
– Collecting reference turbulence measurements in flat terrain with a line of 10 SWUF-3D drones in the neutral boundary layer.
– First night-time measurements with single UAS.
NearWake (FKZ 03EE3097B) is funded by the German Federal Ministry for Economic Affairs and Climate Action (BMWK) based on a resolution of the German Bundestag.
https://www.enargus.de/pub/bscw.cgi/?op=enargus.eps2&q=nearwake&v=10&s=10&id=31604965
