sensitivity analysis of Operational Modal Approaches in damping identification and implementation on an industrial sample

Authors

1 Departmen of Mechanical Engineering, Najafabad Branch., Islamic Azad University, Najafabad, Iran

2 Ph.D, Material. Eng., Sharif University, Tehran, Iran

3 Departmen of Mechanical Engineering, Najafabad Branch., Islamic Azad University, Najafabad, Iran.

Abstract

It is impossible to measure the random excitation loads of structures during transportation under road excitations or satellite carriers thrown under environmental excitations in order to identify modal parameters; thus in this research, our challenge and purpose is to determine the modal properties of structures without having the input excitation load and, but only by having the response. In the studies have been performed so far in the field of modal analysis, less attention has been paid to comparing time and frequency methods, especially in the determination of damping. In addition, no sensitivity analysis between different excitations of white noise, sinusoidal sweep and the effect of these excitations on time and frequency domain methods of modal functional analysis have been performed so far. At first, these methods are implemented and validated on a 5-DOF discrete model (mass, spring, and damper), and finally they are industrially implemented on an actual structure. This paper shows that the decomposition methods are capable to extract the modal parameters of the primary modes of an actual sample. At the end, a comparison is made between the results and the effectiveness of each method is evaluated.

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Main Subjects

References

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Journal of Solid and Fluid Mechanics
Volume 8, Issue 3
October 2018
Pages 177-192

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