The Pininfarina full-scale automotive wind tunnel was recently upgraded to reach a wind speed of 250-260 Km/h and at the same time to further reduce by some dB, the background noise level in the test section.
The speed increase is aimed at testing high performance cars at speed greater than 200 Km/h.
The decrease of the ambient noise level is aimed at improving the aeroacoustic measurements, both in low and high turbulence flow.
The upgrade was made by adding an array of 13 new fans in the return circuit.
Each fan drive system has a power of 160 KW for a total of 2 MW.
The new fans are operating together with the old main fan (1.1 MW).
However, each new fan has a dedicated control system, so that, if necessary, each fan can have a different rpm or a different blade pitch.
In the meantime, some new noise measuring techniques have been set up to improve and speed up the car aeroacoustic development.
The paper reports the motivation for this wind speed upgrade, the technical details of the work made in the wind tunnel, as well as the results obtained both as increase of top speed and as reduction of background noise.
Some results obtained with the new aeroacoustic measurement techniques are also reported.