Aerodynamic Design Considerations and Shape Optimization of Flying Wings in Transonic Flight

This paper provides a technique that minimize the cruise drag (or maximize L/D) for a blended wing body transport with a number of constraints. The wing shape design is done by splitting the problem into 2D airfoil design and 3D twist optimization with a frozen planform. A 45% to 50% reduction of inviscid drag is nally obtained, with desired pitching moment. The results indicate that further improvement can be obtained by modifying the planform and varying the camber more aggressively.