Vibration Characteristics of Functionally Graded Pre-Twisted Turbo Machinery Blade with Rotational Effect

In the present work the effect of rotation and pretwist angle on free vibration characteristics of functionally graded conical shells are analyzed. The dynamic equilibrium equation considers only moderate rotational speeds for which Coriolis Effect is neglected. The conical shell materials properties are supposed to vary with a powerlaw distribution of the volume fractions of their constituents through their thickness. Convergence studies are performed in respect of mesh sizes, and comparisons of the present solutions and those reported in open literature are provided to verify the accuracy of the present finite element formulation. Computer codes developed to obtain the numerical results for the combined effects of twist angle and rotational speed on the natural frequencies of functionally graded conical shells. The mode shapes for a typical laminate configuration are also illustrated. Numerical results are obtained for the non-dimensional fundamental (NDFF) and second frequencies (NDSF).