A blind test on wind turbine wake modelling based on wind tunnel experiments: Phase II – Active Wake Control

Phase II of the Blind Test campaign introduces active individual blade pitch control to the upstream turbine, challenging participants to simulate advanced wake dynamics. This data set ("Data files.zip") contains the wind tunnel measurement data based on wind tunnel experiments organised under the TWEET-IE project (www.tweet-ie.eu). The experiments were carried-out in the large section 2.5 ×3.5×12 m^3 (H× W × L) of the closed-circuit wind tunnel at NTUA. The set up consistsof two identically scaled wind turbine models (G1 models) which are placed in line with a longitudinal distance of 5D. In the context of Phase II, the upstream turbine was initially tested in its baseline configuration before being subjected to dynamic helix motion, with amplitude ranges of 3° and helix frequency of 𝑓ℎ𝑒𝑙𝑖𝑥 = fβ/fr ∈ [0.7,1.3]. The inflow conditions include both Low and High Turbulence Intensities, while Particle Tracking Velocimetry (PTV) measurements were also conducted within the context of Phase II, in a specified dimensionless helix frequency of 𝑓ℎ𝑒𝑙𝑖𝑥 = 0.82. The turbine models, designed and manufactured by TUM, were instrumented with multiple sensors and actuators and had a diameter of 1.1m. Measurements include velocity, power and loads on the turbines. A detailed description of the experimental set up can be found in the accompanying document ("Data documentation.docx"). File "Submission procedure.zip" includes the format description and the templates of the output data that should be submitted by the participants in the blind test comparison.