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
Chris R. Fuller	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
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	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
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	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
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	thesis1.pdf	934.39 Kb	00:04:19	00:02:13	00:01:56	00:00:58	00:00:04
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