Aerodynamic optimization method of supercritical airfoil geared to the performance of swept and tapered wing

Abstract

This paper presents an aerodynamic optimization method of supercritical airfoil geared to the performance of a swept and tapered wing based on a revised pressure coefficient transformation equation, which considers the tapered/swept effects and the influence of local swept angle, as well as the local curvature effects of supercritical wing. The airfoil optimized by the present method (2.75D method) is assembled to the outboard part of a supercritical wing of a wide body civil airplane. An outboard part of supercritical wing with good performance is achieved through this optimization method. The result of optimization design using 2.75D method is compared with traditional two-to three-dimensional transformation design method (2.5D method) and full three-dimensional optimization design method (3D method). The comparison results show that, when compared with 2.5D method, because of considering local swept angle and local curvature revision, the 2.75D method presented in this paper can reflect the tapered effects of three-dimensional wing in airfoil design, and has better agreement between the pressure distribution of airfoil and the corresponding section on the three-dimensional wing, so that better three-dimensional wing will be found in the optimization; on the other hand, when compared with full three-dimensional design method, the presented 2.75D method will greatly improve the optimization efficiency.