Assessment of the Phase Synchronization Effect in Modal Testing During Operation

The impact-synchronous modal analysis (ISMA), which uses impact-synchronous time averaging (ISTA), allows modal testing to be performed during operation. ISTA is effective in filtering out the non-synchronous cyclic load component, its harmonics, and noises. However, it was found that at operating s...

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Main Authors: Ong, Zhi Chao, Lim, Hong Cheet, Khoo, Shin Yee, Ismail, Zubaidah, Kong, Keen Kuan, Abdul Ghaffar, Abdul Rahman
Format: Article
Language:English
English
Published: Zhejiang University Press 2017
Subjects:
Online Access:http://umpir.ump.edu.my/id/eprint/18424/
http://umpir.ump.edu.my/id/eprint/18424/1/Assessment%20of%20the%20phase%20synchronization%20effect%20in%20modal%20testing%20during%20operation.pdf
http://umpir.ump.edu.my/id/eprint/18424/7/Assessment%20of%20the%20phase%20synchronization%20effect%20in%20modal%20testing%20during%20operation%201.pdf
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author Ong, Zhi Chao
Lim, Hong Cheet
Khoo, Shin Yee
Ismail, Zubaidah
Kong, Keen Kuan
Abdul Ghaffar, Abdul Rahman
author_facet Ong, Zhi Chao
Lim, Hong Cheet
Khoo, Shin Yee
Ismail, Zubaidah
Kong, Keen Kuan
Abdul Ghaffar, Abdul Rahman
author_sort Ong, Zhi Chao
building UMP Institutional Repository
collection Online Access
description The impact-synchronous modal analysis (ISMA), which uses impact-synchronous time averaging (ISTA), allows modal testing to be performed during operation. ISTA is effective in filtering out the non-synchronous cyclic load component, its harmonics, and noises. However, it was found that at operating speeds that coincide with the natural modes, ISMA would require a high number of impacts to determine the dynamic characteristics of the system. This finding has subsequently reduced the effectiveness and practicality of ISMA. Preservation of signatures during ISTA depends on the consistency of their phase angles on every time block but not necessarily on their frequencies. Thus, the effect of phase angles with respect to impact is seen to be a very important parameter when performing ISMA on structures with dominant periodic responses due to cyclic load and ambient excitation. The responses from unaccounted forces that contain even the same frequency as that contained in the response due to impact are diminished with the least number of impacts when the phase of the periodic responses is not consistent with the impact signature for every impact applied. The assessment showed that a small number of averages are sufficient to eliminate the non-synchronous components with 98.48% improvement on simulation and 95.22% improvement on experimental modal testing when the phase angles with respect to impact are not consistent for every impact applied.
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spelling ump-184242017-08-24T07:13:29Z http://umpir.ump.edu.my/id/eprint/18424/ Assessment of the Phase Synchronization Effect in Modal Testing During Operation Ong, Zhi Chao Lim, Hong Cheet Khoo, Shin Yee Ismail, Zubaidah Kong, Keen Kuan Abdul Ghaffar, Abdul Rahman TJ Mechanical engineering and machinery The impact-synchronous modal analysis (ISMA), which uses impact-synchronous time averaging (ISTA), allows modal testing to be performed during operation. ISTA is effective in filtering out the non-synchronous cyclic load component, its harmonics, and noises. However, it was found that at operating speeds that coincide with the natural modes, ISMA would require a high number of impacts to determine the dynamic characteristics of the system. This finding has subsequently reduced the effectiveness and practicality of ISMA. Preservation of signatures during ISTA depends on the consistency of their phase angles on every time block but not necessarily on their frequencies. Thus, the effect of phase angles with respect to impact is seen to be a very important parameter when performing ISMA on structures with dominant periodic responses due to cyclic load and ambient excitation. The responses from unaccounted forces that contain even the same frequency as that contained in the response due to impact are diminished with the least number of impacts when the phase of the periodic responses is not consistent with the impact signature for every impact applied. The assessment showed that a small number of averages are sufficient to eliminate the non-synchronous components with 98.48% improvement on simulation and 95.22% improvement on experimental modal testing when the phase angles with respect to impact are not consistent for every impact applied. Zhejiang University Press 2017 Article PeerReviewed application/pdf en http://umpir.ump.edu.my/id/eprint/18424/1/Assessment%20of%20the%20phase%20synchronization%20effect%20in%20modal%20testing%20during%20operation.pdf application/pdf en http://umpir.ump.edu.my/id/eprint/18424/7/Assessment%20of%20the%20phase%20synchronization%20effect%20in%20modal%20testing%20during%20operation%201.pdf Ong, Zhi Chao and Lim, Hong Cheet and Khoo, Shin Yee and Ismail, Zubaidah and Kong, Keen Kuan and Abdul Ghaffar, Abdul Rahman (2017) Assessment of the Phase Synchronization Effect in Modal Testing During Operation. Journal of Zhejiang University-SCIENCE A, 18 (2). pp. 92-105. ISSN 1673-565X(print); 1862-1775(online) . (Published) https://doi.org/10.1631/jzus.A1600003 DOI: 10.1631/jzus.A1600003
spellingShingle TJ Mechanical engineering and machinery
Ong, Zhi Chao
Lim, Hong Cheet
Khoo, Shin Yee
Ismail, Zubaidah
Kong, Keen Kuan
Abdul Ghaffar, Abdul Rahman
Assessment of the Phase Synchronization Effect in Modal Testing During Operation
title Assessment of the Phase Synchronization Effect in Modal Testing During Operation
title_full Assessment of the Phase Synchronization Effect in Modal Testing During Operation
title_fullStr Assessment of the Phase Synchronization Effect in Modal Testing During Operation
title_full_unstemmed Assessment of the Phase Synchronization Effect in Modal Testing During Operation
title_short Assessment of the Phase Synchronization Effect in Modal Testing During Operation
title_sort assessment of the phase synchronization effect in modal testing during operation
topic TJ Mechanical engineering and machinery
url http://umpir.ump.edu.my/id/eprint/18424/
http://umpir.ump.edu.my/id/eprint/18424/
http://umpir.ump.edu.my/id/eprint/18424/
http://umpir.ump.edu.my/id/eprint/18424/1/Assessment%20of%20the%20phase%20synchronization%20effect%20in%20modal%20testing%20during%20operation.pdf
http://umpir.ump.edu.my/id/eprint/18424/7/Assessment%20of%20the%20phase%20synchronization%20effect%20in%20modal%20testing%20during%20operation%201.pdf