Results of a parametric design study to adapt the structural properties and strain distribution of active twist blades

Rotor Blades, especially active twist blades, have been investigated by DLR (German Aerospace Center) for many years and the feasibility of this technology was shown in several projects. However, many relevant features must be taken into account within the design process. The most challenging aspect is the proper tuning of the structure to integrate the fragile actuators, because they have to sustain a variety of loads, while still providing the expected performance. Further different constraints on bending and torsional stiffness or axes positions of the rotor blade exist. At DLR a tool called SaMaRA (Structural Modelling and Rotor Analysis) was developed. It’s a parametric finite element model to meet these partially conflicting requirements as part of a structural optimization framework. The proposed paper provides an overview of the adaption of structural properties and shows representative results for active twist blades