Title page for ETD etd-100698-135142


Type of Document Master's Thesis
Author Cambou, Pierre E.
URN etd-100698-135142
Title A Distributed Active Vibration Absorber (DAVA) for Active-Passive Vibration and Sound Radiation Control
Degree Master of Science
Department Mechanical Engineering
Advisory Committee
Advisor Name Title
Fuller, Christopher R. Committee Chair
Keywords
  • Variational Method
  • Sound
  • Vibration
  • Dynamic Absorber
  • Genetic Algorithm
  • Active Control
Date of Defense 1998-09-07
Availability unrestricted
Abstract
This thesis presents a new active-passive treatment developed to reduce

structural vibrations and their associated radiated sound. It is a

contribution to the research of efficient and low cost devices that

implement the advantages of active and passive noise control techniques. A

theoretical model has been developed to investigate the potential of this

new "active-passive distributed absorber". The model integrates new

functions that make it extremely stable numerically. Using this model, a

genetic algorithm has been used to optimize the shape of the active-passive

distributed absorber. Prototypes have been designed and their potential

investigated. The device subsequently developed can be described as a skin

that can be mechanically and electrically tuned to reduce unwanted vibration

and/or sound. It is constructed from the piezoelectric material

polyvinylidene fluoride (PVDF) and thin layers of lead. The tested device is

designed to weight less than 10% of the main structure and has a resonance

frequency around 1000 Hz. Experiments have been conducted on a simply

supported steal beam (24"x2"x1/4"). Preliminary results show that the new

treatment out-performs active-passive point absorbers and conventional

constrained layer damping material. The compact design and its efficiency

make it suitable for many applications especially in the transportation

industry. This new type of distributed absorber is totally original and

represent a potential breakthrough in the field of acoustics and vibration

control.

Files
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  appendix_a.pdf 26.93 Kb 00:00:07 00:00:03 00:00:03 00:00:01 < 00:00:01
  appendix_b.pdf 14.26 Kb 00:00:03 00:00:02 00:00:01 < 00:00:01 < 00:00:01
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  appendix_d.pdf 31.31 Kb 00:00:08 00:00:04 00:00:03 00:00:01 < 00:00:01
  appendix_e.pdf 54.81 Kb 00:00:15 00:00:07 00:00:06 00:00:03 < 00:00:01
  Chapter_1.pdf 20.53 Kb 00:00:05 00:00:02 00:00:02 00:00:01 < 00:00:01
  Chapter_2.pdf 189.80 Kb 00:00:52 00:00:27 00:00:23 00:00:11 00:00:01
  Chapter_3.pdf 302.68 Kb 00:01:24 00:00:43 00:00:37 00:00:18 00:00:01
  Chapter_4.pdf 329.18 Kb 00:01:31 00:00:47 00:00:41 00:00:20 00:00:01
  conclusion.pdf 8.99 Kb 00:00:02 00:00:01 00:00:01 < 00:00:01 < 00:00:01
  intro.pdf 7.67 Kb 00:00:02 00:00:01 < 00:00:01 < 00:00:01 < 00:00:01
  ref.pdf 18.82 Kb 00:00:05 00:00:02 00:00:02 00:00:01 < 00:00:01
  thesis1.pdf 934.39 Kb 00:04:19 00:02:13 00:01:56 00:00:58 00:00:04
  vita.pdf 5.25 Kb 00:00:01 < 00:00:01 < 00:00:01 < 00:00:01 < 00:00:01

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