Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6703743 | Composite Structures | 2018 | 10 Pages |
Abstract
The effects of bend-twist coupling on the flutter limits of large composite wind turbine blades are investigated in this work. A mixed, geometrically exact, and nonlinear finite element for anisotropic beams is developed based on Hellinger-Reissner variational principle. The nonlinear beam model is combined with Blade Element Momentum method and an unsteady dynamic stall model to perform flutter analysis of composite blades. A 5-MW composite wind turbine blade with shallow-angled skins is studied, where unbalanced laminates (i.e. ply angle and ply thickness unbalances) are implemented to introduce the bend-twist coupling in the blade through material anisotropy. The results show that with bend-twist coupling due to geometrical nonlinearities, the predicted flutter limits are around 23% lower than the same predicted in linear flutter analysis. The unbalanced skin laminates show no significant influence on the flutter limits of the blade in nonlinear flutter analysis.
Related Topics
Physical Sciences and Engineering
Engineering
Civil and Structural Engineering
Authors
Xiandong Zhou, Kefu Huang, Zheng Li,