Investigation of the dynamic properties of plate-like structures

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2011

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Kahraman, Engin

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This study presents the investigation and the verification of the modal parameters of a plate-like structure by using different modal analysis methods. A fin-like structure which is generally used in aircraft is selected as a subcategory of a plate-like test structure. In the first part of the thesis, the natural frequencies and the corresponding mode shapes of the fin are extracted by Finite Element Analysis method. Classical Modal Analysis and Testing methods comprising both impact hammer and modal shaker applications are then applied in order to obtain the modal parameters such as; resonance frequencies, mode shapes and damping ratios. In the second part, a recent modal analysis technique, Operational Modal Analysis, is also applied in the laboratory environment. Since Operational Modal Analysis method does not require any information of input forcing, the fin structure is tested under both mechanical and acoustical types of excitations without measuring the given input forces. Finally, Operational Modal Analysis and Testing is also performed under various flow conditions generated in the wind tunnel which may simulate the real operating environment for the fin structure. The modal parameters extracted under these flow conditions are then compared with the previously obtained Finite Element, Classical and Operational Modal Analyses results.

Subject Keywords

Aerospace engineering., Mechanics, Applied.

URI

http://etd.lib.metu.edu.tr/upload/12613703/index.pdf
https://hdl.handle.net/11511/21101

Collections

Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

E. Kahraman, “Investigation of the dynamic properties of plate-like structures,” M.S. - Master of Science, Middle East Technical University, 2011.