Abstract
The purpose of the present document is to describe a design proposal for a flexible blade that can adapt its aerodynamic profile and fulfill the “Shape-Morphing concept.” The design is based on the analysis of the geometrical changes that a specific baseline aerodynamic profile must undergo during the shape-morphing process to another aerodynamic profile. The concept design assumes that the arc length of the aerodynamic profiles remains constant; therefore, the cord length changes from one configuration to the other. The proposed mechanism deforms the baseline profile in a way that it assures a continuous path between the aerodynamic forms. To demonstrate the effectiveness of the proposed mechanism, a flexible blade prototype was constructed and tested while morphing from a NACA 0012-based shape to a NACA 4412-based shape. The experimental results indicate that it is possible to implement a shape-morphing mechanism within small wind turbine blades that is able to accurately modify their geometrical shape and, thus, their aerodynamics, providing a novel alternative for control and operation optimization.
