Publication
Title
Absorption measurement of acoustic materials using a scanning laser Doppler vibrometer
Author
Abstract
In this article a method is proposed to estimate the normal incidence reflection ratio and absorption coefficient of acoustical materials using measurements in a transparent tube excited with a loudspeaker and terminated with the material under investigation. The waveforms are measured at different locations in the tube using a scanning laser Doppler vibrometer. Because the measurement probe (i.e., the laser beam) does not interfere with the wave in the tube, narrow tubes can be used. This means that-in contrast to the standardized wide tube tests using microphones-the proposed experiment could be used for high frequencies (in the paper an 8 mm tube was used, resulting in a 25 kHz upper frequency limit). It is shown based on theoretically known scenarios (i.e., an open tube and a rigid termination) that the absorption coefficient can be obtained with an error of about three percent. In addition, the absorption coefficient of two commonly used absorption materials-glass fiber wool and carpet-were determined and found to be in good agreement with material databases. (c) 2005 Acoustical Society of America.
Language
English
Source (journal)
The journal of the Acoustical Society of America. - New York, N.Y.
Publication
New York, N.Y. : 2005
ISSN
0001-4966
Volume/pages
117:31(2005), p. 1168-1172
ISI
000227574700019
Full text (Publisher's DOI)
UAntwerpen
Faculty/Department
[E?say:metaLocaldata.cgzprojectinf]
Publication type
Subject
External links
Web of Science
Record
Identification
Creation 04.11.2014
Last edited 03.11.2017