Windkanal

The invention relates to a wind tunnel (1), in particular for aero-acoustic measuring, with closed air conduction and a free jet measuring section, whereby measures are taken to avoid or at least reduce disruptive aerodynamic oscillation. This is achieved, in accordance with the invention, by fitting a device, in particular one or several loud speaker units (33-35), to initiate aerodynamic oscillations in opposition of phase. This system makes it possible to avoid in particular the phenomenon that occurs in wind tunnels with closed air conduction and free jet working section (so-called Göttinger type), in the form of low frequency aerodynamic oscillation which develops at certain aerodynamic speeds and is likely to generate resonance inside the tunnel.