Natural frequencies of bladed disks by a combined cyclic symmetry and Rayleigh-Ritz method

A combined classical Rayleigh-Ritz and cyclic symmetry method is described for the free vibration analysis of rotating turbo-machinery bladed disk systems. It is shown that the first few lowest natural frequencies can be predicted accurately by taking only one repeatable substructure of the system. The formulation makes use of the shell theory for the blades so that no modes are missed. The accuracy is shown by means of a study of representative samples and comparison with available results.