Static and Dynamic Aerocharacteristics Testing of Strake-Wing Aerial Vehicle in Water Tunnel

Abstract

This paper focuses on flow visualization, normal force and pitch moment testing of the NASA TP-1803 strake-wing model at high attack angles. The dynamic aerocharacteristics for pitching with various reduced frequencies and two sideslip angles ¼ 0 and 10 in the water tunnel are compared with those for static case. For ¼ 20 -50 , the strake/wing vortices breakdown positions occur later for ¼ 10 than for ¼ 0 . The value of the normal force coefficient under sideslip angle ¼ 10 is greater than ¼ 0 at high attack angles. In the pitch-down process, the aerodynamic center creates a nose-up pitching moment and the model becomes unstable compared to the static condition. As the pitch reduced frequency increases, the wing vortices sustain longer flow lines and provide more normal force during pitch-up motion. In addition, the hysteresis loop of the normal force curve is larger for higher reduced frequencies.

Static and Dynamic Aerocharacteristics Testing of Advanced Stealth Aircraft in Water Tunnel

“…They are normal forces (N1, N2), side forces (S1, S2), and rolling moment (RM). The dyed liquid release method 9) was used to visualize flow inside the water tunnel. The approximate Reynolds number (Re) used for observing the vortex flow was based on Elkhoury,6) who proved the Ó 2011 The Japan Society for Aeronautical and Space Sciences intense effect of different values of Re on the structure of vortex flow.…”