Decomposition of frequency response functions into paths

AbstractThe aim of a transfer path analysis (TPA) is to view the transmission of vibrations in a mechanical system from the point of excitation over interface points to a reference point. For that matter, the Frequency Response Functions (FRF) of a system or the Transmissibility Matrix is determined and examined in conjunction with the interface forces at the transfer path. This paper will cover the application of an operational TPA for a wind turbine model. In doing so the path contribution of relevant transfer paths are made visible and can be optimized individually.

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Frequency response functions of circular arches for support motions

Engineering Structures ◽

10.1016/0141-0296(88)90048-x ◽

1988 ◽

Vol 10 (4) ◽

pp. 265-271

Author(s):

S.T. Mau ◽

A.N. Williams

Keyword(s):

Frequency Response ◽

Response Functions ◽

Frequency Response Functions

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Calculation of Component Mode Synthesis Matrices From Measured Frequency Response Functions, Part 2: Application

Journal of Vibration and Acoustics ◽

10.1115/1.2893859 ◽

1998 ◽

Vol 120 (2) ◽

pp. 509-516 ◽

Cited By ~ 5

Author(s):

J. A. Morgan ◽

C. Pierre ◽

G. M. Hulbert

Keyword(s):

Frequency Response ◽

Coupled System ◽

Companion Paper ◽

Component Mode Synthesis ◽

Response Functions ◽

Frequency Response Functions ◽

Measured Frequency ◽

Measured Frequency Response ◽

Coupled Beams ◽

The Individual

This paper demonstrates how to calculate Craig-Bampton component mode synthesis matrices from measured frequency response functions. The procedure is based on a modified residual flexibility method, from which the Craig-Bampton CMS matrices are recovered, as presented in the companion paper, Part I (Morgan et al., 1998). A system of two coupled beams is analyzed using the experimentally-based method. The individual beams’ CMS matrices are calculated from measured frequency response functions. Then, the two beams are analytically coupled together using the test-derived matrices. Good agreement is obtained between the coupled system and the measured results.

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Experimental Study for Extraction of Normal Modes

Volume 3B: 15th Biennial Conference on Mechanical Vibration and Noise — Acoustics, Vibrations, and Rotating Machines ◽

10.1115/detc1995-0461 ◽

1995 ◽

Author(s):

S. Y. Chen ◽

M. S. Ju ◽

Y. G. Tsuei

Keyword(s):

Frequency Response ◽

Normal Mode ◽

Normal Modes ◽

Measurement Data ◽

Mode Shapes ◽

Complex Frequency ◽

Response Functions ◽

Frequency Response Functions ◽

Incomplete System ◽

Coupled Structures

Abstract A frequency-domain technique to extract the normal mode from the measurement data for highly coupled structures is developed. The relation between the complex frequency response functions and the normal frequency response functions is derived. An algorithm is developed to calculate the normal modes from the complex frequency response functions. In this algorithm, only the magnitude and phase data at the undamped natural frequencies are utilized to extract the normal mode shapes. In addition, the developed technique is independent of the damping types. It is only dependent on the model of analysis. Two experimental examples are employed to illustrate the applicability of the technique. The effects due to different measurement locations are addressed. The results indicate that this technique can successfully extract the normal modes from the noisy frequency response functions of a highly coupled incomplete system.

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