Transonic Flow Around a Fan Blade
HS Shadowgraphy at Ma_1=1.22
Shadowgraphs recorded at 10khz, showing the motion of the lambda shock above the suction side as well as vibrations of the blade surface.
PIV Single shots of shock wave boundary layer interaction at a 'fixed' shock position at Ma_1=1.2
The incoming flow upstream of the air involves a low degree of turbulence (Tu1=0.5%). The transitional boundary layer exhibits strong flow separations.
The incoming flow upstream of the air involves a high degree of turbulence (Tu1=2.5%). The transitional boundary layer exhibits weak flow separations . Large vortices occur occasionally.
PIV Conditional averages sorted by shock position at Ma1=1.22
Sequence showing the mean velocity field at 'fixed' shock positions obtained by sorting of 10,000 samples followed by conditional averaging. The transitional separation bubble is highlighted through the red line showing an estimated dividing streamline. These conditional averages clearly indicate an increasing size of the separation region with increasing chord-wise shock position.