Method for Designing Leading-Edge Fillets to Eliminate Flow Separation

A design method is presented whereby the flow separation in the wing–fuselage juncture of aircraft is eliminated by the use of a leading-edge fillet. The design method uses a design rule that relates a change in skin friction to a change in surface slope. After determining the current skin-friction distribution on the plate ahead of the leading edge of the wing, a target skin-friction distribution that will eliminate flow separation is calculated. By the use of the design rule, the current skin-friction distribution is moved toward the target distribution by extending the leading edge of the wing to form a leading-edge fillet. The new leadingedge fillet is then analyzed by the flow solver and the process is iterated until convergence is achieved.