Title page for ETD etd-09172001-144121


Type of Document Master's Thesis
Author Blanc, Arthur
Author's Email Address arthur.blanc@voila.fr
URN etd-09172001-144121
Title Control of Sound Radiation From Structures with Periodic Smart Skins
Degree Master of Science
Department Mechanical Engineering
Advisory Committee
Advisor Name Title
Fuller, Christopher R. Committee Chair
Burdisso, Ricardo A. Committee Member
Johnson, Martin E. Committee Member
Keywords
  • bending waves
  • smart skin
  • sound radiation
  • periodic structures
  • structural acoustics
Date of Defense 2001-07-27
Availability unrestricted
Abstract
An innovative implementation of the skin concept for the reduction of the radiated sound power from a vibrating structure is proposed. The skin has a periodic structure and continuously covers a vibrating beam. Thus, this skin decouples the vibrating structure from the acoustic field by modifying the wavenumber spectrum of the radiating surface. First, structural acoustics and periodic structure theories are reviewed in order to predict how bending waves propagate along a periodic beam and how this beam radiates sound. These theories are then extended to the case of multi-layered structures in order to understand the behavior of a beam loaded with a periodic skin. In order to design the beam and skin structural periods, two different methods are used: Galois sequences and an optimization process using a real-valued genetic algorithm. Simulations are run for the case of periodic beams and beams coupled with periodic smart skins in both finite and infinite configurations. Results show that periodic beam can radiate less sound than equivalent uniform structures. Results also show the potential of periodic skin for application to the structural radiation problem for frequencies higher than approximately 100Hz with an approximately 10dB of radiated sound power attenuation.
Files
  Filename       Size       Approximate Download Time (Hours:Minutes:Seconds) 
 
 28.8 Modem   56K Modem   ISDN (64 Kb)   ISDN (128 Kb)   Higher-speed Access 
  Blanc_MsThesis.pdf 3.38 Mb 00:15:39 00:08:03 00:07:02 00:03:31 00:00:18

Browse All Available ETDs by ( Author | Department )

dla home
etds imagebase journals news ereserve special collections
virgnia tech home contact dla university libraries

If you have questions or technical problems, please Contact DLA.