Operational modal analysis of a ship model in the presence of harmonic excitation

被引：0
作者：
Xu J. [1 ]
Hong M. [1 ]
Liu X. [1 ]
机构：
[1] State Key Laboratory of Structural Analysis for Industrial Equipment, Dalian University of Technology, Dalian
来源：
Journal of Marine Science and Application | 2013年 / 12卷 / 1期
基金：
中国国家自然科学基金;
关键词：
eigensystem realization algorithm (ERA); harmonic excitation; modal parameters identification; natural excitation technique (NExT); operational model analysis; ship model; ship structure; signal processing;
D O I：
10.1007/s11804-013-1167-8
中图分类号：
学科分类号：
摘要：
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. © 2013 Harbin Engineering University and Springer-Verlag Berlin Heidelberg.
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页码：38 / 44
页数：6
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