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This study focuses on the corner flow separation occurring in a simplified wing-body junction composed of a NACA0015 twisted wing mounted on a flat plate at a Reynolds number based on the wing chord of Re c 1.2 × 10 6 . Wind-tunnel test measurements are carried out in the corner area including extensive oil-flow visualizations, high speed particle image velocimetry and unsteady pressure sensors. The analysis of the experimental database shows that the corner flow separation creates mean flow distortions that induce high anisotropy in the Reynolds stresses and turbulent kinetic energy. The wall pressure spectra show a broadband hump associated with the corner flow separation at St δ 0.04, based on the incoming boundary layer thickness. A sensitivity study indicates the progressive growth of the corner flow separation with increasing angle of attack, leading to complete wing stall and the delay of the corner flow separation onset when the incoming boundary layer is thicker.

This paper describes the first application of 3D density reconstruction from a limited number of background oriented schlieren (BOS) images in a large research-type low speed wind tunnel. The tested flow is an ad hoc co-flowing hot jet generated at the wingtip of a simplified airfoil. Ray deviation maps captured by 12 synchronized cameras are combined to reconstruct the three dimensional density field of the jet, in the line of the direct 3D BOS technique described in Nicolas et al (2016 Exp. Fluids 57 1–21). A comparison with thermocouple sampling shows consistent results and highlights the efficiency of this new method for thermal measurement of a low speed convective flow. Finally, we underline the new possibilities for fluid dynamic characterization offered by combining stereo particle image velocimetry and 3D BOS measurements.