Écoulement en bord de fuite d'un profil NACA 4412 morphé par un actionnement hybride

This study is part of the RTRA-DYNAMORPH (Dynamic regimes Electroactive Morphing) research program and presents the development of a new electro active morphing concept based on a hybridization of different spatial and temporal scales. This article presents this new midscale prototype based on a NACA 4412 profile. The main goal of the developed prototype is to validate the integration of the innovative actuators able to reach large deformations and high frequencies of even under realistic aerodynamic loads. Characterization and 22 eme Congres Francais de Mecanique Lyon, 24 au 28 Aout 2015 integration of two different families of materials will be investigated. In a first part the actuation by surface embedded NiTInol alloys is presented and in a second step MFC (Macro Fiber Composite) actuators capable of small and fast deformations will be introduced. Furthermore, the effects of the large-amplitude low frequency actuation modifying the airfoil's camber are investigated using aerodynamic force measurement at IMFT’s wind tunnel. Particle image velocimetry (PIV) measurements are conducted at the MFC actuated trailing edge in order to investigate the physical effect on the flow of the high-frequency low-amplitude forcing. A statistical analysis of these results reveals the reduction of the Reynolds stress tensor components with increasing actuation frequency up to a frequency of 60 Hz. Finally the obtained results will be summarized and discussed to evaluate benefit of this morphing strategy. Mots clefs : morphing, alliage a memoire de forme, MFC, piezoelectrique, aeroelasticite, PIV.