Wind tunnel measurements
Laminar Wind Tunnel
The Laminar Wind Tunnel (LWT) is an Eiffel-type wind tunnel with a test section of 0.73m × 2.73m and 3.15m length and a turbulence level of Tux = 0.02% (f = 20 ? 5000Hz) at 30m/s. It has a maximum operation speed of 90m/s. Its very low turbulence level makes it ideal for laminar boundary layer measurements and investigations of wind turbine airfoils. The measurement techniques of the LWT includes standard polar, pressure distribution, transition detection, boundary layer, two-point turbulent correlation, wall pressure fluctuations etc, acoustics measurement by microphone array and hot-wire based Coherent Particle Velocity (CPV) methods. Recently, the LWT was modified significantly and equipped with a sound absorbing lining in the diffusor between fan and test section.
Gust Wind Tunnel
The Gust Wind Tunnel is an Eiffel-type wind tunnel with a test section of 6.3m of diameter and a flow velocity of 17m/s. It is especially built for experiments with wind turbines under steady flow conditions as well as under gust loads.