Computer techniques for airfoil design

This paper describes the application of the analogue solution of distributed parameter systems to the airfoil design problem. Conformal transformations are used to convert the boundary value problem, described by a laplacian field with exterior type of boundary conditions, to a set of initial value problems. The method is shown to render non-linear ordinary differential equations in which the streamlines themselves are functions of the describing behaviour, such as the analogue solution may only be brought about by incorporating generalized integrators with the conventional analogue computer. This method is shown to provide a complete analogue determination of airfoil shapes of various aerodynamic lifting magnitude and the corresponding fluid flow patterns for any angle of attack and fluid speed. Compared with existing alternative methods, the present method has the advantages of higher accuracy, provides a means for a rapid online modelling and ease of changeable design parameters at a shorter computation time. The succes of the method has established its validity and confirmed its application generality.