Experimental research on flying-wing by PIV in high speed wind tunnel

A PIV experimental investigation has been made in 2.4m transonic wind tunnel. The item, include 2D and stereo PIV test, and the resluts show that the deviation of the PIV results from calibration results are less than 1% when M≤0.8 and less than 2% when M=0.9. The low-aspect-ratio flying-wing model test shows that the vorticity and tangential velocity of wake increases and the vortex core moves closer as Mach number increases. The leading edge vortex has direct relationship with the flow seperation. The leading edge vortex doesn't break in test region while M=0.8 and α ≤12°and there is no significant flow seperation visible. When α ≥13°, the leading edge vortex breaks, in advance, and significant flow seperation can be observed after 1/2 chord length of the wing.