The Calculation of the Loading and Pressure Distribution on Cranked Wings

Abstract

Using distributions of vortices and sources over the aerofoil surface, approximate formulae are developed for finding the spanwise and chordwise loadings of cranked wings (i.e., wings with discontinuous changes of sweep), and the chordwise pressure distribution at the crank, in incompressible flow. The method can be extended to subcritical compressible flow by considering the 'analogous wing.' Calculations by the present method are compared with experimental results on two wings and with calculations by another method for wings of M, W and A plan-form. Agreement with experiment is good. Comparison with the other method shows satisfactory agreement between the spanwise loadings, but the present method yields more information about chordwise distributions, and is quicker.