Center Body Airfoil Design for Blended Wing Body Configuration

To design the center-body airfoil of a blended wing body configuration, the aerodynamic effects of the symmetrical airfoil, trailing-edge reflexed airfoil, leading-edge loaded airfoil and leading- edge loaded plus trailing-edge reflexed airfoil are investigated based on the constraints of system arrangement. A 150-passenger BWB configuration is studied; for a center-body with symmetrical airfoil, the larger outer-wing geometrical twist should be used to fulfill the positive zero-lift pitching moment according to the design requirements of longitudinal static stability, however, lift to drag ratio shows a big decrease. For leading-edge loaded airfoil, it is difficult to achieve a positive zero-lift pitching moment because of the platform limitation. For trailing-edge reflexed airfoil or leading- edge loaded plus trailing-edge reflexed airfoil, it is easy to achieve ideal design results when reasonably designing the leading- edge loading and trailing-edge unloading. The application of a blended wing body UAV shows that the loss of aerodynamic characteristics is small when adopting the "eagle hook" stealth leading edge that has the characteristics of leading edge loading.