Simulation of the Automation of Composite Wind Turbine Blade Manufacture

Abstract

The majority of large wind turbine blades are manufactured from textile-reinforced resin-infused composites using an open mold. The placement of the textile reinforcements in the mold is traditionally accomplished by a manual process where dozens of workers hand place each dry fabric in the mold. Depending on the level of skill and experience of each worker and the relative complexity of the mold geometry, local areas may exhibit out-of-plane wrinkling and in-plane waviness. Fabric imperfections such as these can adversely impact the strength and stiffness of the blade, thereby compromising its durability in service. In an effort to reduce the variabilities associated with a manual-labor process, an automated piecewise shifting method has been proposed for fabric placement. This automated layup method shows potential to save time on the preform process and to reduce blade-to-blade variability. In the current research, the automated shifting layup method is investigated using the finite element modeling approach. A user-defined material model is linked with Abaqus to capture the evolution of the fabric shear stiffness, and the modeling approach allows for the automatic tracking of the changes in the fiber orientations during the fabric-placement process. The simulation approach is demonstrated for the geometry of the trailing edge of a typical wind turbine blade. The simulation considers the mechanical behavior of the fabric and reliably predicts fabric deformation.