File Download

There are no files associated with this item.

  Links for fulltext
     (May Require Subscription)
Supplementary

Article: Combined action of transverse oscillations and uniform cross-flow on vortex formation and pattern of a circular cylinder

TitleCombined action of transverse oscillations and uniform cross-flow on vortex formation and pattern of a circular cylinder
Authors
KeywordsOscillating cylinder
PIV
Vortices
Issue Date2010
PublisherAcademic Press. The Journal's web site is located at http://www.elsevier.com/locate/jfs
Citation
Journal Of Fluids And Structures, 2010, v. 26 n. 5, p. 703-721 How to Cite?
AbstractThis paper attempts to study the roles of lateral cylinder oscillations and a uniform cross-flow in the vortex formation and wake modes of an oscillating circular cylinder. A circular cylinder is given lateral oscillations of varying amplitudes (between 0.28 and 1.42 cylinder-diameters) in a slow uniform flow stream (Reynolds number=284) to produce the 2S, 2P and P+S wake modes. Detailed flow information is obtained with time-resolved particle-image velocimetry and the phase-locked averaging techniques. In the 2S and 2P mode, the flow speeds relative to the cylinder movement are less than the uniform flow velocity and it is found that initial formation of a vortex is caused by shear-layer separation of the uniform flow on the cylinder. Subsequent development of the shear-layer vortices is affected by the lateral cylinder movement. At small cylinder oscillation amplitudes, vortices are shed in synchronization with the cylinder movement, resulting in the 2S mode. The 2P mode occurs at larger cylinder oscillation amplitudes at which each shear-layer vortex is found to undergo intense stretching and eventual bifurcation into two separate vortices. The P+S mode occurs when the cylinder moving speeds are, for most of the time, higher than the speed of the uniform flow. These situations are found at fast and large-amplitude cylinder oscillations in which the flow relative to the cylinder movement takes over the uniform flow in governing the initial vortex formation. The formation stages of vortices from the cylinder are found to bear close resemblance to those of a vortex street pattern of a cylinder oscillating in an otherwise quiescent fluid at Keulegan-Carpenter numbers around 16. Vortices in the inclined vortex street pattern so formed are then convected downstream by the uniform flow as the vortex pairs in the 2P mode. © 2010 Elsevier Ltd.
Persistent Identifierhttp://hdl.handle.net/10722/137243
ISSN
2015 Impact Factor: 1.709
2015 SCImago Journal Rankings: 1.282
ISI Accession Number ID
Funding AgencyGrant Number
Research Grants Council of Hong KongHKU7144/05E
Funding Information:

The investigation is supported by a research grant (HKU7144/05E) awarded by the Research Grants Council of Hong Kong.

References

 

DC FieldValueLanguage
dc.contributor.authorLam, KMen_HK
dc.contributor.authorLiu, Pen_HK
dc.contributor.authorHu, JCen_HK
dc.date.accessioned2011-08-26T14:21:41Z-
dc.date.available2011-08-26T14:21:41Z-
dc.date.issued2010en_HK
dc.identifier.citationJournal Of Fluids And Structures, 2010, v. 26 n. 5, p. 703-721en_HK
dc.identifier.issn0889-9746en_HK
dc.identifier.urihttp://hdl.handle.net/10722/137243-
dc.description.abstractThis paper attempts to study the roles of lateral cylinder oscillations and a uniform cross-flow in the vortex formation and wake modes of an oscillating circular cylinder. A circular cylinder is given lateral oscillations of varying amplitudes (between 0.28 and 1.42 cylinder-diameters) in a slow uniform flow stream (Reynolds number=284) to produce the 2S, 2P and P+S wake modes. Detailed flow information is obtained with time-resolved particle-image velocimetry and the phase-locked averaging techniques. In the 2S and 2P mode, the flow speeds relative to the cylinder movement are less than the uniform flow velocity and it is found that initial formation of a vortex is caused by shear-layer separation of the uniform flow on the cylinder. Subsequent development of the shear-layer vortices is affected by the lateral cylinder movement. At small cylinder oscillation amplitudes, vortices are shed in synchronization with the cylinder movement, resulting in the 2S mode. The 2P mode occurs at larger cylinder oscillation amplitudes at which each shear-layer vortex is found to undergo intense stretching and eventual bifurcation into two separate vortices. The P+S mode occurs when the cylinder moving speeds are, for most of the time, higher than the speed of the uniform flow. These situations are found at fast and large-amplitude cylinder oscillations in which the flow relative to the cylinder movement takes over the uniform flow in governing the initial vortex formation. The formation stages of vortices from the cylinder are found to bear close resemblance to those of a vortex street pattern of a cylinder oscillating in an otherwise quiescent fluid at Keulegan-Carpenter numbers around 16. Vortices in the inclined vortex street pattern so formed are then convected downstream by the uniform flow as the vortex pairs in the 2P mode. © 2010 Elsevier Ltd.en_HK
dc.languageengen_US
dc.publisherAcademic Press. The Journal's web site is located at http://www.elsevier.com/locate/jfsen_HK
dc.relation.ispartofJournal of Fluids and Structuresen_HK
dc.subjectOscillating cylinderen_HK
dc.subjectPIVen_HK
dc.subjectVorticesen_HK
dc.titleCombined action of transverse oscillations and uniform cross-flow on vortex formation and pattern of a circular cylinderen_HK
dc.typeArticleen_HK
dc.identifier.openurlhttp://library.hku.hk:4550/resserv?sid=HKU:IR&issn=0889-9746&volume=26&issue=5&spage=703&epage=721&date=2010&atitle=Combined+action+of+transverse+oscillations+and+uniform+cross-flow+on+vortex+formation+and+pattern+of+a+circular+cylinder-
dc.identifier.emailLam, KM:kmlam@hku.hken_HK
dc.identifier.authorityLam, KM=rp00134en_HK
dc.description.naturelink_to_subscribed_fulltext-
dc.identifier.doi10.1016/j.jfluidstructs.2010.03.007en_HK
dc.identifier.scopuseid_2-s2.0-77955658945en_HK
dc.identifier.hkuros190696en_US
dc.relation.referenceshttp://www.scopus.com/mlt/select.url?eid=2-s2.0-77955658945&selection=ref&src=s&origin=recordpageen_HK
dc.identifier.volume26en_HK
dc.identifier.issue5en_HK
dc.identifier.spage703en_HK
dc.identifier.epage721en_HK
dc.identifier.eissn1095-8622-
dc.identifier.isiWOS:000281982500002-
dc.publisher.placeUnited Kingdomen_HK
dc.identifier.scopusauthoridLam, KM=7403656958en_HK
dc.identifier.scopusauthoridLiu, P=35799939000en_HK
dc.identifier.scopusauthoridHu, JC=9846591400en_HK
dc.identifier.citeulike7149420-

Export via OAI-PMH Interface in XML Formats


OR


Export to Other Non-XML Formats