A morphing trailing edge device for a wind turbine

Abstract

The loads on wind turbine components are primarily from the blades. It is important to control these loads in order to avoid damaging the wind turbine. Rotor control technology is currently limited to controlling the rotor speed and the blade pitch. As blades increase in length, it becomes less desirable to pitch the entire blade as a single rigid body, but there is a requirement to control loads more precisely along the length of the blade. This can be achieved with aerodynamic control devices such as flaps. Morphing structures are good candidates for wind turbine flaps because they have the potential to create structures that have the conflicting abilities of being load carrying, lightweight and shape adaptive. A morphing flap design with an anisotropic cellular structure is presented, which is able to undergo large deflections and high strains. An aeroelastic analysis couples the work done by aerodynamic loads on the flap, the flap strain energy and the required actuation work to change shape. The morphing flap model is manufactured, and its stiffness is measured.