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The free vibrations of simply supported magneto-electro-elastic cylindrical shells are studied. A series solution is assumed in the circumferential and axial directions of the shell to preserve the three-dimensional character of the structure. The constitutive equations of the magneto-electro-elastic medium involving mechanical, electrical and magnetic fields are used to derive the finite element model for the system. The influence of the piezomagnetic effect on the structural frequencies of the cylindrical shell is studied. A comparison is made between a shell with a layered configuration and one with a multiphase system. The study is carried out for a typical shell with simply supported boundary conditions for different ratios of length to radius and radius to thickness to analyse the frequency behaviour.

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The misalignment between the journal and the bearing in a rotor-bearing system may be due to manufacturing error, elastic deflection, thermal expansion etc. In the present work, the eight linearized stiffness and damping coefficients of the cylindrical and three lobe bearings are identified at different levels of bearing misalignment (twisting misalignment) and at different speeds of the rotor. The identification method used here needs FRFs (Frequency Response Functions) obtained by the measurements and the finite element method. The twisting misalignment changes the stiffness and damping coefficients in the vertical and horizontal directions. In the case of three lobe bearings, for 0.7 degree of misalignment, the stiffness in the vertical direction is increased by about 12 percent.