Modal Modification of Damped Asymmetric Systems without Using the Left Eigenvectors

Abstract:

This study focuses on the prediction of complex eigenpairs of modified asymmetric systems. A method, which combines the reduced basis and the projection technique, is presented to predict the eigenpairs of modified asymmetric systems. The reduced basis obtained using the homotopy perturbation technique only requires the eigensolution of interest such that the modal truncation problem can be avoided. More importantly, the method can be carried out without using the left eigenvectors. The accuracy of the reduced basis approximation can be improved by introducing the projection technique. A rotor dynamic system is used to illustrate the capacity of predicting the changes of eigensolutions.

• Periodical: Applied Mechanics and Materials (Volumes 490-491)
• Pages: 331-335
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.490-491.331
• Online since: January 2014
• Authors: Li Li*, Yu Jin Hu, Xue Lin Wang
• Keywords: Damped Asymmetric System, Reanalysis, Rotor, Structural Modification

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