Experimental Modal Analysis of a Half-Scale Business Jet Fuselage Tail Section
Loading...
Authors
Sekijoba, John
Date
Type
thesis
Language
eng
Keyword
Experimental Modal Analysis , Vibrations , Noise Attenuation , SIgnal Processing
Alternative Title
Abstract
Structure borne noise caused by the engine is a significant source of discomfort for business aircraft passengers. Aircraft with fuselage mounted engines have increased structure borne noise levels in the cabin due to the shortened vibration transmission path. Working with a prominent Canadian aircraft manufacturer, the research objective was to characterize the structural dynamics of the aircraft rear cabin bulkhead experimentally. This is an initial step for structural dynamic modifications (SDM) which will yield reduced noise output and increased passenger comfort. Experimental modal analysis (EMA) identified dynamic properties of the fuselage (i.e. natural frequencies, mode shapes) which were used to validate a FE model. This information will guide structural dynamic modifications, reducing vibration levels in the structure. This research involved using modal testing with an electromechanical shaker to excite a half-scale model aft fuselage tail section at the engine support yokes and measuring the response at the cabin rear bulkhead. The fuselage was excited in three different directions and the results compared with the various driving points and the FE model. The bandwidth of interest was 50 to 400 Hz. This thesis reviews relevant literature and details modal analysis theory, fuselage construction, methodology of excitation, validation techniques, and results. This thesis provides a method for conducting EMA on large, complex structures. The FE and experimental model exhibited five correlated mode pairs. Furthermore, by model updating the FE model, the eigenvalue discrepancy with the experimental model was reduced from 10% to 8%.
Description
Citation
Publisher
License
Queen's University's Thesis/Dissertation Non-Exclusive License for Deposit to QSpace and Library and Archives Canada
ProQuest PhD and Master's Theses International Dissemination Agreement
Intellectual Property Guidelines at Queen's University
Copying and Preserving Your Thesis
This publication is made available by the authority of the copyright owner solely for the purpose of private study and research and may not be copied or reproduced except as permitted by the copyright laws without written authority from the copyright owner.
Attribution 4.0 International
ProQuest PhD and Master's Theses International Dissemination Agreement
Intellectual Property Guidelines at Queen's University
Copying and Preserving Your Thesis
This publication is made available by the authority of the copyright owner solely for the purpose of private study and research and may not be copied or reproduced except as permitted by the copyright laws without written authority from the copyright owner.
Attribution 4.0 International