Publications Details
Uncertainties in prediction of wind turbine blade flutter
Resor, Brian R.; Paquette, Joshua P.
The blades of a modern wind turbine are critical components central to capturing and transmitting most of the loads experienced by the system. Blades are complex structural items composed of many layers of fiber and resin composite material and typically, one or more shear webs. Simplification of the blade structure into equivalent beams is an important step prior to aeroelastic simulation of the turbine structure. There are a variety of approaches that can be used to reduce the three-dimensional continuum blade structure to a simpler beam representation: two-dimensional cross section analysis, extraction of equivalent properties from three-dimensional blade finite element models and variational asymptotical beam sectional analysis. This investigation provides insight into discrepancies observed in outputs from these three approaches for a real blade geometry. Wind turbine blades of the future will be longer and more flexible as weight is optimized. Innovative large blade designs may present challenges with respect to aeroelastic flutter instabilities. Sensitivity of computed flutter speed with respect to variations in computed beam properties is demonstrated at the end of this paper. Copyright © 2011 by the American Institute of Aeronautics and Astronautics, Inc.