An extension to the method of Garabedian and Korn for the calculation of transonic flow past an aerofoil to include the effects of a boundary layer and wake

Abstract

A numerical method has been developed for calculating compressible (inclu- ding transonic) flow past a single aerofoil with an allowance for viscous effects, providing that the boundary layer is fully attached over the aerofoil surface. This method has been developed by combining an iterative scheme for the inviscid flow, originally established by Garabedian and Korn, with an integral method (the lag entrainment method of Green et al) for the calculation of compressible turbulent boundary layers. The inviscid scheme has been modified to incorporate a boundary condition on the aerofoil surface, which is imposed on the velocity normal to the surface, with a corresponding boundary condition for the wake. Wake curvature effects are also included. An iterative procedure is established, which iterates between successive calculations of the pressure distribution and of the displacement thickness of the boundary layer and wake. Results are presented from a computer program (VGK) and comparisons are made with experimental measurements and other theoretical results.