FFT-based spectral dynamic analysis for linear discrete dynamic systems

• Autorzy: Lee U. , Cho J.
• Języki publikacji: EN

Abstrakty

EN

Purpose: An FFT-based spectral dynamic analysis method is developed for the viscously damped, linear discrete dynamic systems subjected to nonzero initial conditions. Design/methodology/approach: The discrete Fourier transform (DFT) theory is used to develop a spectral dynamic analysis method. The dynamic response of a linear system is assumed as the sum of the forced and free vibration response parts. The forced vibration response part is obtained by convolving the dynamic stiffness matrix and Fourier components of excitation force through the Duhamel's integral, and the free vibration response part is obtained by determining its integral constants so as to satisfy initial conditions in frequency-domain. Findings: It is shown through some numeral examples that the proposed FFT-based spectral dynamic analysis method provides the solutions which accurately satisfy all initial conditions. Practical implications: This analysis method is applicable to viscously damped, linear discrete dynamic systems subjected to nonzero arbitrary initial conditions. In this study, two types of viscous damping are considered: proportional damping and non-proportional damping. Originality/value: The FFT-based spectral dynamic analysis method proposed in this paper is unique because the pseudo-force concept or the superposition of corrective free vibration solution used by other researchers is not used to take into account non-zero initial conditions.

Słowa kluczowe

EN

numerical techniques; linear discrete system; spectral analysis method; spectral analysis; fast Fourier transform; FFT

PL

techniki numeryczne; system liniowy; system dyskretny; metody analizy spektralnej; analiza spektralna; szybka transformata Fouriera; FFT

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2007
• Tom: Vol. 25, nr 1
• Strony: 95--102
• Opis fizyczny: Bibliogr. 15 poz., rys.

Twórcy

autor

Lee U.

autor

Cho J.

• Department of Mechanical Engineering, Inha University, Incheon 402-751, South Korea,

Bibliografia

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