“…Compared to the transfer matrix, the finite element method has the advantage of accurately modeling rotor bearing systems with a fewer number of elements while being less sensitive to numerical instabilities, although sometimes it requires more CPU time and computer storage (Ruhl and Booker, 1972). On the other hand, with the transfer matrix approach, as problem size increases, numerical difficulties arise (Uhrig, 1966 (1963,1965), Ruhl and Booker (1972) used cubic hermitian-shape functions to formulate the shaft element matrices, including only the elastic bending energy and kientic energy. Using the Rayleigh beam theory, Nelson and McVaugh (1976) generalized the work of Ruhl and Booker by the addition of other factors, such as rotatry inertia, gyroscopic moments, and axial load.…”