An Economic Approach to Accurate Wing Design

An interactive boundary-layer method is described for computing three-dimensional transonic flows on wing/body configurations. The method combines Euler solutions with viscous flow solutions obtained from an inverse boundary-layer method with an interaction law based on the extension of the Hilbert integral formulation used for two-dimensional flows. Depending on the complexity of the flowfield, two versions of Keller's box scheme are used, the regular box scheme in regions of positive crossflow and no separation, and the characteristic box scheme in regions of negative crossflow and flow separation.

Preliminary calculations performed for a modern transport wing show good agreement with experimental data and indicate that wing/body configurations in transonic flows can be analyzed with good accuracy with this method at substantial savings of computer time.