A Residual Correction Method Applied to 2D Multi-Point Airfoil Design and 3D Single-Point Wing Design

Results are presented of a residual correction method to solve the multi-point airfoil design problem for subsonic and transonic conditions. The method is based on full-potential theory and minimizes a cost function weighting the deviations from specified target pressure distributions for each design condition in a least squares sense. Deviations from specified target pressure distributions (residuals) are translated into airfoil geometry corrections, by means of an approximate inverse calculation using a linearized panel method. The feasibility of introducing an equivalent incompressible multi-point design problem is demonstrated for a two-point reconstruction test case. First results of a two-point example airfoil design case are presented. The applicability of the residual correction methodology to 3D single-point wing design is demonstrated as well.