European Conference on Computational Fluid Dynamics ECCOMAS CFD 2006 P. Wesseling, E. Oñate, J. Périaux (Eds)  TU Delft, The Netherlands, 2006 REALISTIC HIGH-LIFT DESIGN OF TRANSPORT AIRCRAFT BY APPLYING NUMERICAL OPTIMIZATION Jochen Wild † , Joel Brezillon † , Ralf Mertins ‡ , Domenico Quagliarella § , Eric Germain # , Olivier Amoignon ¶ , and Frederic Moens $ † DLR, Institute of Aerodynamics and Flow Technology, Lilienthalplatz 7, 38108 Braunschweig Germany e-mail: Jochen.Wild@dlr.de , Joel.Brezillon@dlr.de Web page: http://www.dlr.de/as ‡ Airbus Germany GmbH, Aerodynamic Design and Data, Hünefeldstraße 1-5, 28199 Bremen, Germany e-mail: Ralf.Mertins@airbus.com § CIRA, Applied Aerodynamics Laboratory, Via Maiorise, 81043 Capua, Italy e-mail: d.quagliarella@citra.it Web page: http://ww.cira.it # ETW European Transonic Windtunnel GmbH, Ernst Mach Straße, D-51147 Köln, Germany e-mail: erg@etw.de Web page: http://www.etw.de ¶ FOI, Aeronautics Division, FFA, 172 90 Stockholm, Sweden e-mail: amo@foi.se Web page: http://www.foi.se $ ONERA, Applied Aerodynamics Department, 29 Avenue de la division Leclerc, 92322 Châtillon, France e-mail: Frederic.Moens@onera.fr Web page: http://www.onera.fr Key words: Optimization, High-Lift, Application, CFD, Wind tunnel testing Abstract. The design activity within the EUROLIFT II project is targeted towards an improvement of the take-off performance of a generic transport aircraft configuration by a re- design of the trailing edge flap. The involved partners applied different optimization strategies as well as different types of flow solvers in order to cover a wide range of possible approaches for aerodynamic design optimization. The optimization results obtained by the different partners have been cross-checked in order to eliminate solver dependencies and to identify the best obtained design. The final selected design has been applied to the wind tunnel model and the test in the European Transonic Wind Tunnel (ETW) at high Reynolds number confirms the predicted improvements.