Estimating Rotational Frequency Response Function Using Mode Expansion and Frequency Response Function Synthesis Method

• Published in: International Journal of Automotive and Mechanical Engineering
• Main Author: Mirza W.I.I.W.I.; Rani M.N.A.; Yunus M.A.; Stancioiu D.; Shripathi V.
• Format: Article
• Language: English
• Published: Universiti Malaysia Pahang 2021
• Online Access: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85110564521&doi=10.15282%2fijame.18.2.2021.11.0667&partnerID=40&md5=8768f38ed1f9014b6c01181d75884e0f

The rotational frequency response function (RFRF) plays a crucial role in increasing the accuracy of the calculated results of the frequency-based substructuring method. However, RFRFs are often omitted due to the difficulties in the measurement process and limitations of the equipment. This paper presents a scheme of estimating the rotational FRF of an irregular plate structure using the FE model reduction and expansion method. The reduced FE model was introduced using the improved reduction system (IRS) and expanded to the experimental modal model (EMA model) using the system reduction and the expansion (SEREP) method. The FRF expanded method was then employed to derive the translational and rotational FRFs from the expanded EMA model. The accuracy of the expanded FRFs was evaluated with the EMA model of the irregular plate. It was found that the translational and rotational FRFs estimated from the proposed scheme were in good agreement with the EMA counterparts. Furthermore, the patterns of the estimated RFRFs were well correlated with the EMA RFRFs. This work shows that the proposed scheme may offer an attractive alternative way of accurately determining the RFRs of complex structures or structural components. © The Authors 2019. Published by Penerbit UMP. This is an open access article under the CC BY license.