Rotor blades as curved, twisted and tapered beam-like structures subjected to large deflections

Non-prismatic beam-like structures are widespread in many engineering and science applications. Important examples include the rotor blades of wind turbines and helicopters. Their mechanical behaviour can be simulated using 3D beam models, which are computationally efficient, accurate and explicitly consider such structures’ main geometric features, the large deflection of their reference centre-line and 3D warping of their transverse cross-sections. This paper proposes a mathematical model for such structures. A variational approach and the smallness of the warping and strain fields are exploited to obtain the model. Analytical and numerical results obtained with the proposed modelling approach are presented and compared to those from nonlinear 3DFEM simulations.