This article presents an experimental evaluation of a morphing leading edge demonstrator by investigating its morphed shape, the level of induced strains in the airfoil skin, the actuation force, and the morphing mechanism’s capability to lock and transfer the applied loads. In addition, a finite element model of the demonstrator is assembled comprising an elastic morphing skin and a kinematic morphing mechanism. The obtained results are used to assess whether the demonstrator performs according to the design objectives, such as the target shape, the character of the morphing deformation and the morphing mechanism locking, applied during the design process. The comparison between experimental and numerical results yielded a good agreement in terms of observed morphed shape and pertaining strains. The average difference in morphed shape was less than 0.08% chord at the maximum actuator extension. The observed difference in the respective strains was less than 400 micro-strains. A significant difference, up to 70%, was observed in the actuation force, which was attributed to the modelling assumptions and to the force measurement technique employed in the experiment. Nevertheless, both results show good qualitative agreement showing similar trends.

The objective of the research presented in this paper was to investigate the design of a droop nose configuration for a regional airliner by using numerical aeroelastic methods. These toolsets were developed at the Delft University of Technology (DUT) and made the study possible between the interaction of the input actuation load, aerodynamic loading and the final target deformation profile of the morphing leading edge high-lift system. An appropriate characterisation of the deformation behaviour of a morphing leading edge high-lift system with respect to the actuation load input would provide valuable information for future design of such morphing leading edge high-lift devices and the definition of their actuation force input. This brings about future possibilities to develop seamless morphing leading edge technology for regional airliners. A set of static discrete forces was applied to the model to represent the aerodynamic loads acting on the leading edge skin. The conceptual design of the layout of the prototype leading edge was done using an actuation topology optimisation routine embedded in DUT aeroelastic toolset. Interpretation of the actuation topology optimisation results was required to define the final actuation system layout for the morphing leading edge high-lift system. The initial stages of the research show positive results in the target deformation. They show a claim-shell motion that maintains a zero stretching behaviour in the skin. Additional studies were conducted in assessing the deflection of the skin in the primary and secondary load conditions. The conclusion yielded a need to design additional actuation members, to control and lock the motion of the actuation system. This was presented by means of four-bar mechanisms. The design, production and tests of the actuation system demonstrator are presented in this work.