MORPHING COMPLIANT TRAILINGEDGE SKIN CONCEPT

Kurzfassung

Many different concepts for morphing trailing edges (TE) have been investigated during the last decades. Within the internal project morphAIR (Morphing Technologies & Artificial Intelligence Research Group) the German Aerospace Center (DLR) is planning further steps by investigating morphing technologies in scaled flight tests. In these flight tests, major effects of morphing technology are going to be shown. Due to having a small-scale demonstrator, former TE concepts need to be evaluated according to applicability, positive lift to drag (L/D) effects and associated weight penalties. Since large deformations are to be achieved typically in a hingeless-elastic system, high actuation forces are required in order to enable morphing. These internal structural loads are crucial for actuator and kinematic design, thus they are directly related to actuator and kinematic weight. Therefore, it is essential to have a measure of required size and weight during preliminary design processes. Within this work, four different methods are presented to derive the strain energy of a new compliant morphing TE system. Beginning with a geometrical linear analytical approach considering small deformations (Model I), over a nonlinear analytical approach incorporating large deformations (Model II), to geometric nonlinear Finite Element Method (FEM) calculations without (Model III) as well as including Fluid Structure Interaction (FSI) (Modell IV). Results of Modell I to IV are compared according to strain energy and virtual Forces. It has been shown that even Model I shows good correlation of deformations and strain energy.