Comparison of Stress Distributions between Numerical Cross-Section Analysis and 3D Analysis of Tapered Beams

While the demand for new and longer wind turbine blades is increasing, time for their design and production is shortening. 3D finite element models generally have the capability of providing a complete and detailed analysis of the behaviour of such structures. Nonetheless, computationally efficient and accurate cross-section analysis tools are required to improve the efficiency of the workflow in the conceptual design phase. Several cross-section analysis software, such as BEam Cross-Section Analysis Software BECAS, have been developed for analysis of prismatic beams. As a result, structures which are tapered along their longitudinal axis, i.e. aircraft wings or wind turbine blades, are modelled as step-wise prismatic beams and the known effects on stresses due to taper are ignored. This study provides a numerical comparison of the Cauchy’s stress components evaluated with both 3D finite element and cross-section analysis consisting of linear elastic isotropic and anisotropic materials. Results highlight how every cross-section formulation that relies on the stepwise prismatic assumption lacks the capability to correctly recover the stresses in tapered beams.