File Download
 
Links for fulltext
(May Require Subscription)
 
Supplementary

Conference Paper: Active tonal noise control for a computer cooling fan
  • Basic View
  • Metadata View
  • XML View
TitleActive tonal noise control for a computer cooling fan
 
AuthorsWang, J1
Huang, L1
 
Issue Date2005
 
CitationProceedings Of 2005 Asme Fluids Engineering Division Summer Meeting, Fedsm2005, 2005, v. 2005, p. 423-432 [How to Cite?]
 
AbstractThe noise sources on a blade can be divided into a thrust force component along the rotating axis, and a drag component on the fan rotational plane. The radiated noise is a result of acoustic interference among all blades, and the two source components. For a sample fan with B=7 blades, and S=7 struts, the drag noise is expected to cancel themselves out. The result is a simple thrust dipole along the fan axis. When 5=7 and S=4, however, the dominant noise is a rotating drag dipole. This paper demonstrates, experimentally, the global elimination of the blade passing frequency tones from the thrust dipole and the rotating drag dipole for the two sample fans, respectively, by using a simple open-loop, feedforward control scheme. The rig consists of a miniature electret microphone used as a rotation sensor, ordinary loudspeakers, and a bandpass filter with adjustable amplitude and phase delay. The electret microphone is installed flush with the inlet bellmouth of the fan. It picks up the fluctuating aerodynamic pressure caused by the passing rotor blades, and is shown to perform much better than a normal optical tachometer. Copyright © 2005 by ASME.
 
ReferencesReferences in Scopus
 
DC FieldValue
dc.contributor.authorWang, J
 
dc.contributor.authorHuang, L
 
dc.date.accessioned2012-08-08T09:04:48Z
 
dc.date.available2012-08-08T09:04:48Z
 
dc.date.issued2005
 
dc.description.abstractThe noise sources on a blade can be divided into a thrust force component along the rotating axis, and a drag component on the fan rotational plane. The radiated noise is a result of acoustic interference among all blades, and the two source components. For a sample fan with B=7 blades, and S=7 struts, the drag noise is expected to cancel themselves out. The result is a simple thrust dipole along the fan axis. When 5=7 and S=4, however, the dominant noise is a rotating drag dipole. This paper demonstrates, experimentally, the global elimination of the blade passing frequency tones from the thrust dipole and the rotating drag dipole for the two sample fans, respectively, by using a simple open-loop, feedforward control scheme. The rig consists of a miniature electret microphone used as a rotation sensor, ordinary loudspeakers, and a bandpass filter with adjustable amplitude and phase delay. The electret microphone is installed flush with the inlet bellmouth of the fan. It picks up the fluctuating aerodynamic pressure caused by the passing rotor blades, and is shown to perform much better than a normal optical tachometer. Copyright © 2005 by ASME.
 
dc.description.naturelink_to_subscribed_fulltext
 
dc.identifier.citationProceedings Of 2005 Asme Fluids Engineering Division Summer Meeting, Fedsm2005, 2005, v. 2005, p. 423-432 [How to Cite?]
 
dc.identifier.epage432
 
dc.identifier.scopuseid_2-s2.0-33646555140
 
dc.identifier.spage423
 
dc.identifier.urihttp://hdl.handle.net/10722/158960
 
dc.identifier.volume2005
 
dc.languageeng
 
dc.relation.ispartofProceedings of 2005 ASME Fluids Engineering Division Summer Meeting, FEDSM2005
 
dc.relation.referencesReferences in Scopus
 
dc.titleActive tonal noise control for a computer cooling fan
 
dc.typeConference_Paper
 
<?xml encoding="utf-8" version="1.0"?>
<item><contributor.author>Wang, J</contributor.author>
<contributor.author>Huang, L</contributor.author>
<date.accessioned>2012-08-08T09:04:48Z</date.accessioned>
<date.available>2012-08-08T09:04:48Z</date.available>
<date.issued>2005</date.issued>
<identifier.citation>Proceedings Of 2005 Asme Fluids Engineering Division Summer Meeting, Fedsm2005, 2005, v. 2005, p. 423-432</identifier.citation>
<identifier.uri>http://hdl.handle.net/10722/158960</identifier.uri>
<description.abstract>The noise sources on a blade can be divided into a thrust force component along the rotating axis, and a drag component on the fan rotational plane. The radiated noise is a result of acoustic interference among all blades, and the two source components. For a sample fan with B=7 blades, and S=7 struts, the drag noise is expected to cancel themselves out. The result is a simple thrust dipole along the fan axis. When 5=7 and S=4, however, the dominant noise is a rotating drag dipole. This paper demonstrates, experimentally, the global elimination of the blade passing frequency tones from the thrust dipole and the rotating drag dipole for the two sample fans, respectively, by using a simple open-loop, feedforward control scheme. The rig consists of a miniature electret microphone used as a rotation sensor, ordinary loudspeakers, and a bandpass filter with adjustable amplitude and phase delay. The electret microphone is installed flush with the inlet bellmouth of the fan. It picks up the fluctuating aerodynamic pressure caused by the passing rotor blades, and is shown to perform much better than a normal optical tachometer. Copyright &#169; 2005 by ASME.</description.abstract>
<language>eng</language>
<relation.ispartof>Proceedings of 2005 ASME Fluids Engineering Division Summer Meeting, FEDSM2005</relation.ispartof>
<title>Active tonal noise control for a computer cooling fan</title>
<type>Conference_Paper</type>
<description.nature>link_to_subscribed_fulltext</description.nature>
<identifier.scopus>eid_2-s2.0-33646555140</identifier.scopus>
<relation.references>http://www.scopus.com/mlt/select.url?eid=2-s2.0-33646555140&amp;selection=ref&amp;src=s&amp;origin=recordpage</relation.references>
<identifier.volume>2005</identifier.volume>
<identifier.spage>423</identifier.spage>
<identifier.epage>432</identifier.epage>
</item>
Author Affiliations
  1. Hong Kong Polytechnic University