Open this publication in new window or tab >>2016 (English)In: Applied Acoustics, ISSN 0003-682X, E-ISSN 1872-910X, Vol. 111, p. 67-76Article in journal (Refereed) Published
Abstract [en]
Studies dedicated to the determination of acoustic characteristics of an automotive cooling package are presented. A shrouded subsonic axial fan is mounted in a wall separating an anechoic- and a reverberation room. This enables a unique separation of the up- and downstream sound fields. Microphone measurements were acquired of the radiated sound as a function of rotational speed, fan type and components included in the cooling module. The aim of the present work is to investigate the effect of a closely mounted radiator upstream of the impeller on the SPL spectral distribution. Upon examination of the SPL spectral shape, features linked specifically to the source and system are revealed. The properties of a reverberant sound field combined with the method of spectral decomposition permit an estimation of the source spectral distribution and the acoustic transfer response, respectively. Additionally, purely intrinsic acoustic properties of the radiator are scrutinized by standardized ISO methods. A new methodology comprising a dipole sound source is adopted to circumvent limitation of transmission loss measurement in the low frequency range. The sound attenuation caused by the radiator alone was found to be negligible.
Place, publisher, year, edition, pages
Elsevier, 2016
Keywords
Fan noise, Insertion loss, Installation effects, Spectral decomposition, Transmission loss, Acoustic field measurement, Acoustic fields, Acoustic properties, Acoustics, Architectural acoustics, Cooling, Fans, Insertion losses, Radiators, Reverberation, Wave transmission, Acoustic characteristic, Heavy duty vehicles, Reverberation rooms, Spectral distribution, Audio signal processing
National Category
Fluid Mechanics and Acoustics
Identifiers
urn:nbn:se:kth:diva-186888 (URN)10.1016/j.apacoust.2016.04.004 (DOI)000377837700008 ()2-s2.0-84962788665 (Scopus ID)
Note
QC 20160524
2016-05-242016-05-162017-11-30Bibliographically approved