Modal Analysis of Linear Asymmetric Nonconservative Systems
Publication: Journal of Engineering Mechanics
Volume 125, Issue 12
Abstract
In this work, classical modal analysis has been extended to treat lumped parameter asymmetric linear dynamic systems. In the presence of general nonconservative forces, the damping matrix is not simultaneously diagonalizable with the mass and stiffness matrices. The proposed method utilizes left and right eigenvectors of the second-order system and does not require conversion of the equations of motion into the first-order form. Left and right eigenvectors of the nonconservative system are derived in terms of the left and right eigenvectors of the corresponding conservative system using a Galerkin error minimization approach in conjunction with a Neumann expansion method. Transfer functions for the asymmetric nonconservative system are derived in terms of the left and right eigenvectors of the nonconservative system. Suitable numerical examples are given to illustrate the proposed method.
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Information & Authors
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Published In
Journal of Engineering Mechanics
Volume 125 • Issue 12 • December 1999
Pages: 1372 - 1379
History
Received: May 26, 1999
Published online: Dec 1, 1999
Published in print: Dec 1999
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