Aerodynamic Design Methodology for Blended Wing Body Transport

Abstract

This paper puts forward a design idea for blended wing body (BWB). The idea is described as that cruise point, maximum lift to drag point and pitch trim point are in the same flight attitude. According to this design idea, design objectives and constraints are defined. By applying low and high fidelity aerodynamic analysis tools, BWB aerodynamic design methodology is established by the combination of optimization design and inverse design methods. High lift to drag ratio, pitch trim and acceptable buffet margin can be achieved by this design methodology. For 300-passenger BWB configuration based on static stability design, as compared with initial configuration, the maximum lift to drag ratio and pitch trim are achieved at cruise condition, zero lift pitching moment is positive, and buffet characteristics is well. Fuel burn of 300-passenger BWB configuration is also significantly reduced as compared with conventional civil transports. Because aerodynamic design is carried out under the constraints of BWB design requirements, the design configuration fulfills the demands for interior layout and provides a solid foundation for continuous work.