Detail publikace

Using Acoustic Holography for Vibration Analysis

HAVRÁNEK, Z.

Originální název

Using Acoustic Holography for Vibration Analysis

Typ

dizertace

Jazyk

angličtina

Originální abstrakt

The main aim of the thesis is application of near-field acoustic holography for noncontact vibration analysis. Near-field acoustic holography is an experimental technique for reconstruction of sound field close to the surface of the vibrating object based on measurement of sound pressure or acoustic particle velocity in certain distance from the examined object. Practical realization of this method depends on used calculation procedure. The thesis is focused on analysis of acoustic holography algorithms with transformation into wavenumber domain (spatial transformation) where the reconstruction of the sound field near vibrating object is calculated. The introductory part of the thesis describes the theory of near-field acoustic holography with general characteristics and with analysis of most common algorithms used for localization and characterization of sound source and consequent vibration analysis. Principal part of the thesis deals with advanced processing methods where these methods try to optimize the accuracy of prediction of sound field near vibrating object in real environment. In this study, real measurement conditions represent the measurement system with non-ideal acoustic sensors and also areas with reverberant sound field. Based on literature study, there has been optimized and verified the new method which uses double layer microphone array to separate incoming and outgoing sound field, thus allows successful measurement in confined space e.g. cabins of cars and airplanes. Part of the thesis has been also focused on optimization, extension and successive experimental validation of selected classical algorithms published in last decade for possible measurement in real conditions and with common acoustic sensors.

Klíčová slova

near-field acoustic holography, vibration analysis, sound source localization, microphone arrays, non-contact measurement, acoustic sensors, array measurement systems

Autoři

HAVRÁNEK, Z.

Vydáno

31. 8. 2009

Nakladatel

VUT Brno

Místo

Brno

Strany počet

115

BibTex

@phdthesis{BUT67018,
  author="Zdeněk {Havránek}",
  title="Using Acoustic Holography for Vibration Analysis",
  publisher="VUT Brno",
  address="Brno",
  pages="115",
  year="2009"
}