Surface Vorticity Theory for Axisymmetric Potential Flow past Annular Aerofoils and Bodies of Revolution with Application to Ducted Propellers and Cowls

Abstract

The well known surface vorticity method originally due to Martensen for calculating two-dimensional aerofoil and cascade flows is extended to axisymmetric flows past annular aerofoils, bodies of revolution and interacting combinations of these. A variety of solutions is presented in comparison with experimental test or classical solutions. A generalized surface vorticity integral equation for fully three-dimensional flow is developed in curvilinear co-ordinates from which the two-dimensional axisymmetric equations are shown to be reducible. This paper is aimed at ship ducted propeller problems but is of wider application to fan cowls, nozzles, bodies of revolution or engine intakes.