Citation:
Junchen Xu,Ming Hong and Xiaobing Liu.Operational Modal Analysis of a Ship Model in the Presence of Harmonic Excitation[J].Journal of Marine Science and Application,2013,(1):38-44.[doi:10.1007/s11804-013-1167-8]
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Operational Modal Analysis of a Ship Model in the Presence of Harmonic Excitation
Junchen Xu,Ming Hong and Xiaobing Liu.Operational Modal Analysis of a Ship Model in the Presence of Harmonic Excitation[J].Journal of Marine Science and Application,2013,(1):38-44.[doi:10.1007/s11804-013-1167-8]
Info
- Title:
- Operational Modal Analysis of a Ship Model in the Presence of Harmonic Excitation
- Author(s):
- Junchen Xu; Ming Hong and Xiaobing Liu
- Affilations:
- Keywords:
- natural excitation technique (NExT); eigensystem realization algorithm (ERA); ship structure; harmonic excitation; signal processing; modal parameters identification; ship model; operational model analysis
- DOI:
- 10.1007/s11804-013-1167-8
- Abstract:
- A ship is operated under an extremely complex environment, and waves and winds are assumed to be the stochastic excitations. Moreover, the propeller, host and mechanical equipment can also induce the harmonic responses. In order to reduce structural vibration, it is important to obtain the modal parameters information of a ship. However, the traditional modal parameter identification methods are not suitable since the excitation information is difficult to obtain. Natural excitation technique-eigensystem realization algorithm (NExT-ERA) is an operational modal identification method which abstracts modal parameters only from the response signals, and it is based on the assumption that the input to the structure is pure white noise. Hence, it is necessary to study the influence of harmonic excitations while applying the NExT-ERA method to a ship structure. The results of this research paper indicate the practical experiences under ambient excitation, ship model experiments were successfully done in the modal parameters identification only when the harmonic frequencies were not too close to the modal frequencies.
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Memo
- Memo:
- Supported by the National Natural Science Foundation of China (51079027).
