An improved high‑lift aerodynamic prediction method for transport aircraft

The aim of this work is the development of a methodology to predict lift characteristics for transport aircraft in the whole flight envelope, useful in the preliminary aircraft design stage. The purpose is an attempt to improve the classical methodologies for wing load distribution and lift prediction, applicable to both clean and flapped configuration. This has been obtained considering the airfoils’ aerodynamic characteristics until stall and post-stall conditions during the process, and modifying 2D characteristics in the case of high-lift devices to take into account 3D effects introduced by the devices themselves. The method is a modification of standard vortex-lattice procedures which are capable of predicting wing aerodynamic characteristics. As regards the clean configuration, the enhanced method works by integrating airfoil characteristics, whereas as far as the high-lift devices’ effect is concerned, the improved method works by substituting clean airfoil aerodynamic characteristics for the flapped aerodynamics ones, and introducing a correction to evaluate the 3D effects induced by the high-lift devices’ geometrical discontinuities. The methodology is explained separately for these two configurations. The results of the developed method have been compared with CFD and experimental data showing good agreement, making available a fast and reliable method useful in preliminary aircraft design phase.