Acoustic properties of perforates under high level multi-tone excitation
2013 (English)In: 19th AIAA/CEAS Aeroacoustics Conference, American Institute of Aeronautics and Astronautics, 2013Conference paper (Refereed)
This paper discusses the effect of high level multi-tone acoustic excitation on the acoustic properties of perforates. It is based on a large experimental study of the nonlinear properties of these types of samples without mean grazing or bias flow. Compared to previously published results the present investigation concentrates on the effect of multiple harmonics. It is known from previous studies that high level acoustic excitation at one frequency will change the acoustic impedance of perforates at other frequencies, thereby changing the boundary condition seen by the acoustic waves. This effect could be used to change the impedance boundary conditions and for instance increase the absorption. It could obviously also pose a problem for the correct modelling of sound transmission through ducts lined with such impedance surfaces. Experimental results are compared to a quasi-stationary model. The effect of the combination of frequency components and phase in the excitation signal is studied.
Place, publisher, year, edition, pages
American Institute of Aeronautics and Astronautics, 2013.
Acoustic excitation, Excitation signals, Frequency components, Impedance boundary conditions, Impedance surface, Multiple harmonics, Nonlinear properties, Sound transmission
Fluid Mechanics and Acoustics
IdentifiersURN: urn:nbn:se:kth:diva-133290DOI: 10.2514/6.2013-2175ScopusID: 2-s2.0-84883738892ISBN: 978-162410213-4OAI: oai:DiVA.org:kth-133290DiVA: diva2:660476
19th AIAA/CEAS Aeroacoustics Conference; Berlin; Germany; 27 May 2013 through 29 May 2013
QC 201310302013-10-302013-10-292014-11-17Bibliographically approved