Publication Date
2013
Document Type
Thesis
Committee Members
Ha-rok Bae (Committee Member), Ramana Grandhi (Advisor), Gregory Reich (Committee Member)
Degree Name
Master of Science in Engineering (MSEgr)
Abstract
The configurations for high speed, low observable aircraft expose many critical areas on the structure to extreme environments of intense acoustic pressure loadings. When combined with primary structural and thermal loads, this effect can cause high cycle fatigue to aircraft skins and embedded exhaust system components. In past aircraft design methods, these vibro-acoustic loads have often been neglected based on their relatively small size compared to other thermal and structural loads and the difficulty in capturing their dynamic and frequency dependent responses. This approach is insufficient for effective advanced designs of complex aerospace structures, such as internal ducted exhaust systems and sensitive airframes. By optimizing the integrated aircraft components that involve interactions between fluid and structural coupled systems, the structural stresses created from the high acoustic pressure magnitude of the frequency response functions can be reduced, therefore prolonging the fatigue life of the aircraft structure. This research investigates acoustic excitations generated by structurally integrated acoustic pressure sources and explores the coupling effects of the fluid and structure domains. Utilizing a hybrid optimization scheme that comprises both global and local optimization methods, acoustic related stresses and mass can be simultaneously reduced in these highly dynamic and frequency dependent structural-acoustic aerospace systems.
Page Count
134
Department or Program
Department of Mechanical and Materials Engineering
Year Degree Awarded
2013
Copyright
Copyright 2013, all rights reserved. This open access ETD is published by Wright State University and OhioLINK.
