Design of a contourvariable droop nose

A process chain for the development of a flexible and gapless wing leading edge is being evolved within the framework of the Sonderforschungsbereich 880 (SFB880). The main topic of the research is to achieve an exceedingly high degree of leading edge morphing which is a key technology for realizing an actively blown Coand˘a-flap based high lift system. In contrast to the state of the art smart droop nose concepts the novel high lift system within SFB880 requires considerably more droop (> 300 %) than achieved before. Thus, a new approach based on optimization of the skin and the actuation kinematics in a loop is chosen. An additional feature of the new approach is the application of compliant mechanisms for a beneficial distribution of the skin loads. The content of this paper is formed by the detailed presentation of the framework for topology optimization of a composite skin combined with actuation kinematics. The skin must be deformable and bear the aerodynamical loads. Thus, after discussing important structural requirements, a corrugated skin design with an emphasis on the deformation limits is investigated