Response Spectral Density for Oscillators with Nonlinear Damping
Publication: Journal of Engineering Mechanics
Volume 133, Issue 3
Abstract
The concept of equivalent nonlinearization is used to obtain approximate solutions for the frequency response function and power spectral density (PSD) function of the response for oscillators with nonlinear damping. When harmonic excitation is considered the energy of the response is assumed to oscillate around a mean energy level. Assuming that the response is harmonic with energy-dependent amplitude an approximate frequency response function is obtained. The PSD function of the response to white noise excitation at a given energy level is obtained by an expression similar to the expression for a linear system, where the damping is replaced by an energy-dependent damping function. The total PSD function is obtained as a weighted average of the damping at all energy levels, and the method can be considered an extension of the method of equivalent nonlinearization to the frequency domain. The accuracy of the methods is verified by numerical examples.
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Acknowledgments
This project has been supported by the Danish Technical Research Council. The support is gratefully acknowledged.
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Information & Authors
Information
Published In
Journal of Engineering Mechanics
Volume 133 • Issue 3 • March 2007
Pages: 278 - 289
Copyright
© 2007 ASCE.
History
Received: Jun 1, 2005
Accepted: May 22, 2006
Published online: Mar 1, 2007
Published in print: Mar 2007
Notes
Note. Associate Editor: Joel P. Conte
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