Dynamic response with arbitrary initial conditions using the FFT

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

Abstrakty

EN

Purpose: An FFT-based dynamic analysis method is proposed for damped linear discrete dynamic systems subjected to arbitrary nonzero initial conditions. Design/methodology/approach: The DFT theory is used to develop an FFT-based spectral analysis method. The total dynamic response is considered as the sum of the forced vibration response part and the free vibration response part. The forced vibration response part is obtained from the dynamic stiffness matrix and the Fourier components of excitation force based on the concept of Duhamel’s integral, and the free vibration response part is obtained by determining its integral constant to satisfy arbitrary initial conditions in the frequency-domain. Findings: Through some numeral examples, the proposed FFT-based dynamic analysis method is shown to provide very successful solutions which satisfy all arbitrary non-zero initial conditions. Research limitations/implications: (not applicable). Practical implications: (not applicable). Originality/value: The present FFT-based method is unique because it does not use the superposition of corrective free vibration solution or the pseudo-force concept used by other researchers to take into account the non-zero initial conditions.

Słowa kluczowe

EN

numerical techniques; spectral analysis method; linear discrete system; FFT

PL

techniki numeryczne; metody analizy spektralnej; system liniowy; system dyskretny; FFT

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2006
• Tom: Vol. 18, nr 1-2
• Strony: 299--302
• Opis fizyczny: Bibliogr. 6 poz., wykr.

Twórcy

autor

Lee U.

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

autor

Cho J.

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

Bibliografia

• [1] D.E. Newland, Random Vibrations, Spectral and Wavelet Analysis. Longman, New York, 1993.
• [2] J.H. Ginsberg, Mechanical and Structural Vibrations: Theory and Applications, John Wiley and Sons, New York, 2001.
• [3] J.L. Humar and H. Xia, Dynamic response analysis in the frequency domain, Earthquake Engineering and Structural Dynamics 22 (1993), 1-12.
• [4] A.S. Veletsos and C.E. Ventura, Dynamic analysis of structures by the DFT method, Journal of Structural Engineering 111 (1985), 2625-2642.
• [5] W.J. Mansur, D. Soares Jr. and M.A.C. Ferro, Initial conditions in frequency-domain analysis: the FEM applied to the scalar wave equation, Journal of Sound and Vibration 270 (2004), 767-780.
• [6] C.T. Sun and J.M. Bai, Vibration of multi-degree-of-freedom systems with non-proportional viscous damping, International Journal of Mechanical Science 37 (1995), 441-455.