Development of optical flow field measurement techniques in the ONERA F1 low-speed wind tunnel

The need to qualify the now field around a model is a constant objective for research activities and industrial aeronautical development programs. The progress in global optical techniques such as Doppler Global Velocimetry (DGV) and Particle Image Velocimetry (PIV) has permitted to make comparative tests in F1 of these two non-intrusive methods and to compare these results to a reference case investigated by a five-hole probe. The ONERA F1 wind tunnel is a low-speed pressurized wind tunnel used by industry as well as research activities. The three components of the velocity field have been measured, half a chord behind the wing of a generic civil aircraft in a landing configuration, where the different vortices emitted from the wing tip and from the flaps are visible. These global methods are of great interest for large wind tunnels, by reducing the measurement time to some seconds for a mean flow field map, compared to hours with the probing systems.