Distributed Parameter Rotor-Bearing Systems
The transverse vibration of rotor systems with distributed mass becomes an important issue when one needs to gain deep insight into the dynamic behavior of rotor systems. As far as the equations of motion are concerned, the complexity of the analysis increases as the rotary inertia [1,2], gyroscopic moments , shear deformation [4,5] and their combined effects [6,7] are taken into account. Regardless of the complexity introduced in rotor models, the resonant frequency, critical speed calculations and stability analysis are relatively straightforward. However, the mode shapes associated with the natural frequencies and thus the forced response analysis(modal analysis) of distributed mass rotor systems with the added complexity are not readily available except in the extremely simple case of an Euler-Bernoulli rotor model(without the gyroscopic terms) [1,8]. It has already been pointed out in the previous chapters that the Euler-Bernoulli rotor model is not a suitable model for investigating those aspects of rotor systems which distinguish them from ordinary structures. The difficulties in modal analysis of rotor systems arise from the fact that their eigenvalue problems are characterized by the presence of skew symmetric matrices with differential operators as elements due to rotation and/or damping, leading to non-self-adjoint eigenvalue problems .
KeywordsModal Frequency Modal Analysis Mode Shape Vibration Analysis Rotor System
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