Abstract
Theoretical and finite element (FE) methods for predicting buckling of wind turbine blades are compared. The theoretical method considers the blade skin as separate panels (idealised as cylindrically curved, simply-supported, and under uniform axial compression); established theory provides the critical load. This approach is compared to FE models of individual panels and representative aerofoils. The FE calculation for an idealised panel agrees with the theory (within 10%). Idealising the panel curvature as cylindrical makes little difference to the critical load (<5%). Adoption of a more realistic load distribution over the length of a blade has greater influence: the buckling strain at the root of a blade under a cubically varying bending moment distribution (e.g. flap-wise bending of a tapered blade under uniform incident wind pressure) is 15% higher than that for an idealised panel. The idealised panel method is therefore a conservative method suitable for preliminary design.
Get full access to this article
View all access options for this article.