Measuring oblique incidence sound absorption using a local plane wave assumption

Research output: Contribution to journalArticleAcademicpeer-review

5 Citations (Scopus)
71 Downloads (Pure)

Abstract

In this paper a method for the measurement of the oblique incidence sound absorption coefficient is presented. It is based on a local field assumption, in which the acoustic field is locally approximated by one incident- and one specularly reflected plane wave. The amplitudes of these waves can be determined with an unidirectional sound intensity probe. The local active- and incident acoustic intensity are straightforwardly obtained. The area-averaged sound absorption coefficient is calculated after spatial integration of these quantities over the surface area of interest. Alternatively, one may use a three-dimensional intensity probe. In that case, the determination of the amplitudes of the plane waves can be formulated as a least-squares problem. Measurements performed for a sound absorbing foam demonstrate that accurate results can be obtained, even under non-ideal acoustic conditions. Measurements carried out for a periodic absorber show that the method is accurate below the cut-on frequency of scattering as long as the amplitude of the evanescent surface waves is significantly smaller than that of the specularly reflected wave.
Original languageEnglish
Pages (from-to)205-214
JournalAcustica united with Acta Acustica
Volume100
DOIs
Publication statusPublished - 2014

Fingerprint

sound transmission
plane waves
incidence
acoustics
absorptivity
sound intensity
probes
reflected waves
foams
surface waves
absorbers
Waves
Sound
scattering
Acoustics

Keywords

  • IR-94383
  • METIS-297481

Cite this

@article{d14401081adb400baea4d0e6c2bcaae8,
title = "Measuring oblique incidence sound absorption using a local plane wave assumption",
abstract = "In this paper a method for the measurement of the oblique incidence sound absorption coefficient is presented. It is based on a local field assumption, in which the acoustic field is locally approximated by one incident- and one specularly reflected plane wave. The amplitudes of these waves can be determined with an unidirectional sound intensity probe. The local active- and incident acoustic intensity are straightforwardly obtained. The area-averaged sound absorption coefficient is calculated after spatial integration of these quantities over the surface area of interest. Alternatively, one may use a three-dimensional intensity probe. In that case, the determination of the amplitudes of the plane waves can be formulated as a least-squares problem. Measurements performed for a sound absorbing foam demonstrate that accurate results can be obtained, even under non-ideal acoustic conditions. Measurements carried out for a periodic absorber show that the method is accurate below the cut-on frequency of scattering as long as the amplitude of the evanescent surface waves is significantly smaller than that of the specularly reflected wave.",
keywords = "IR-94383, METIS-297481",
author = "E.R. Kuipers and Wijnant, {Ysbrand H.} and {de Boer}, Andries",
year = "2014",
doi = "10.3813/AAA.918700",
language = "English",
volume = "100",
pages = "205--214",
journal = "Acustica united with Acta Acustica",
issn = "1610-1928",
publisher = "S. Hirzel Verlag GmbH",

}

Measuring oblique incidence sound absorption using a local plane wave assumption. / Kuipers, E.R.; Wijnant, Ysbrand H.; de Boer, Andries.

In: Acustica united with Acta Acustica, Vol. 100, 2014, p. 205-214.

Research output: Contribution to journalArticleAcademicpeer-review

TY - JOUR

T1 - Measuring oblique incidence sound absorption using a local plane wave assumption

AU - Kuipers, E.R.

AU - Wijnant, Ysbrand H.

AU - de Boer, Andries

PY - 2014

Y1 - 2014

N2 - In this paper a method for the measurement of the oblique incidence sound absorption coefficient is presented. It is based on a local field assumption, in which the acoustic field is locally approximated by one incident- and one specularly reflected plane wave. The amplitudes of these waves can be determined with an unidirectional sound intensity probe. The local active- and incident acoustic intensity are straightforwardly obtained. The area-averaged sound absorption coefficient is calculated after spatial integration of these quantities over the surface area of interest. Alternatively, one may use a three-dimensional intensity probe. In that case, the determination of the amplitudes of the plane waves can be formulated as a least-squares problem. Measurements performed for a sound absorbing foam demonstrate that accurate results can be obtained, even under non-ideal acoustic conditions. Measurements carried out for a periodic absorber show that the method is accurate below the cut-on frequency of scattering as long as the amplitude of the evanescent surface waves is significantly smaller than that of the specularly reflected wave.

AB - In this paper a method for the measurement of the oblique incidence sound absorption coefficient is presented. It is based on a local field assumption, in which the acoustic field is locally approximated by one incident- and one specularly reflected plane wave. The amplitudes of these waves can be determined with an unidirectional sound intensity probe. The local active- and incident acoustic intensity are straightforwardly obtained. The area-averaged sound absorption coefficient is calculated after spatial integration of these quantities over the surface area of interest. Alternatively, one may use a three-dimensional intensity probe. In that case, the determination of the amplitudes of the plane waves can be formulated as a least-squares problem. Measurements performed for a sound absorbing foam demonstrate that accurate results can be obtained, even under non-ideal acoustic conditions. Measurements carried out for a periodic absorber show that the method is accurate below the cut-on frequency of scattering as long as the amplitude of the evanescent surface waves is significantly smaller than that of the specularly reflected wave.

KW - IR-94383

KW - METIS-297481

U2 - 10.3813/AAA.918700

DO - 10.3813/AAA.918700

M3 - Article

VL - 100

SP - 205

EP - 214

JO - Acustica united with Acta Acustica

JF - Acustica united with Acta Acustica

SN - 1610-1928

ER -