Wind Turbine Cross-Sectional Stiffness Analysis Using Internally Layered Solid Elements

An efficient finite element modeling approach is presented for analyzing the general cross-sectional stiffness properties and stress distribution of thin- and thick-walled sections with isotropic and general anisotropic materials. The procedure is based on discretizing the walls of the section using a single layer of displacement-based elements whereby the element's stiffness is obtained using Gaussian quadrature through each layer. The interlaminar stresses are recovered at points of interest via a three-dimensional equilibrium-based postprocessing scheme that uses the distribution of in-plane stress gradients derived in the local laminate coordinate system. The theory is illustrated by application to three composite sections of various shapes and material layups.