Study on the distortion effect of flying wing in low speed wind tunnel

Flying wing is becoming one of the ideal aerodynamic configurations for military and civil aircraft because of its excellent aerodynamic efficiency and stealth performance. In order to acquire the effect of local configuration distortion due to sting support, a test study on low aspect ratio flying wing based on incremental method is carried out in CARDC FL-14 low speed wind tunnel. Both the afterbody distortion model and the calibration model are tested to investigate the distortion effect by means of antitheses method, and the comparison among the results of other three low speed wind tunnels with near-field/far-field support interference are presented. It is shown that the distortion effect is significantly stronger than support interference at small angle of attack and equivalent at medium and high angle of attack as the side slip angle is small. The distortion effect is more important in lateral direction than longitudinal direction, and intensified with the increasing angle of side slip. Test results is needed to be corrected and local afterbody configuration be optimized to reduce distortion effect.