Assessment of classical, advanced, and layer-wise theories for the vibration of rotating composite anisotropic blades

The present paper aims at studying composite cambered structures, tracking the seminar work “Rotating Blade Vibration Analysis Using Shells” presented by Leissa in Journal of Engineering for Power, in 1982, devoted to homogeneous metallic blades. A refined unidimensional (1D) formulation is here implemented to overcome the limitations of classical beam theories. With an appropriate choice of cross-sectional expansions, it is possible to make the 1D model suitable for analyzing shallow blades. This approach enables one to generate both layerwise (LW) and equivalent single layer (ESL) descriptions of the problem unknowns. Furthermore, it is possible to implement classic theories as special cases. Natural frequencies are determined for isotropic and composite blades, showing the effects of changing the fiber lamination angle of symmetric and unsymmetric configurations. Besides, this study investigates the effects of thickness and rotational speed over the structure. Significant differences between classic and high-order theories are found, concerning the accuracy and the computational costs. The causes of these differences are discussed, and the results can be used as a benchmark for future studies.