Deutsche WindGuard has launched their new acoustic test section at the large scale wind tunnel in Bremerhaven.
The new equipment permits measuring the precise location of noise sources on rotor blade profiles. A special feature of the wind tunnel is that it allows for simultaneous aerodynamic and acoustic measurements on rotor blade profiles with realistic Reynolds-numbers. This way, all necessary measurements can be performed in one wind tunnel with the same model in an integrated measurement campaign. For the new acoustic test section they doubled the number of microphones in the acoustical camera to a total of 80. The acoustical sensors are individually incorporated in a casing specifically designed for this purpose. The complex system is completed by special sound absorbers which increase the signal-to-noise-ratio between the model and the wind tunnel. A high-speed thermographic camera is supporting the acoustical measurement system by visualizing the transition line.