In this paper model reduction of an unsymmetric and damped structural system is presented using a two-sided dynamic condensation technique. The method is an iterative one and essentially utilizes orthonormalized complex eigenvectors of the unsymmetric system. The eigensolution of the reduced order model with specified master degrees-of-freedom is obtained by Lanczos algorithm. The model reduction procedure is further utilized in substructure synthesis and eigenvalue analysis of large size unsymmetric systems. Application of the condensation technique is illustrated via two example problems of rotor bearing systems.

Issue Section:
Technical Papers
Keywords:
structural engineering, eigenvalues and eigenfunctions, iterative methods, damping, finite element analysis
Topics:
Bearings, Condensation, Degrees of freedom, Eigenvalues, Rotors
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