Loading…

Force coefficients and Strouhal numbers of four cylinders in cross flow

This paper presents the measurements of force coefficients and Strouhal numbers (St) on four cylinders in a square configuration at subcritical Reynolds numbers (Re) using a piezo-electric load cell in a wind tunnel. Six spacing ratios ( L/D) varying from 1.69 to 3.83 and 13 angles of incidence α ra...

Full description

Saved in:
Bibliographic Details
Published in:Journal of fluids and structures 2003-09, Vol.18 (3), p.305-324
Main Authors: Lam, K, Li, J.Y, So, R.M.C
Format: Article
Language:English
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
cited_by cdi_FETCH-LOGICAL-c416t-57371eda92492953351f74040d41fa4784f99dddb1ed910271eb9679519a708a3
cites cdi_FETCH-LOGICAL-c416t-57371eda92492953351f74040d41fa4784f99dddb1ed910271eb9679519a708a3
container_end_page 324
container_issue 3
container_start_page 305
container_title Journal of fluids and structures
container_volume 18
creator Lam, K
Li, J.Y
So, R.M.C
description This paper presents the measurements of force coefficients and Strouhal numbers (St) on four cylinders in a square configuration at subcritical Reynolds numbers (Re) using a piezo-electric load cell in a wind tunnel. Six spacing ratios ( L/D) varying from 1.69 to 3.83 and 13 angles of incidence α ranging from 0° to 180° at a 15° interval covering all orientations were investigated. With the help of a laser-induced fluorescence visualization technique, it is found that the variation of forces and Strouhal numbers with L/D are governed by three distinct flow patterns. They are: (a) free oscillations of shear layers and vortex formation at large L/D; (b) reattachment of shear layer or shielding flow for intermediate L/D and (c) narrow gap flows for small L/D. Two major causes for large fluctuating forces are discussed in this paper and the force results are compared with other measurements. It is concluded that the flow patterns, i.e., the development and the interferences of the free shear layers and the distribution of the wake vortices of the cylinders play a key role in the variation of the forces and shedding frequencies. Consequently, the downstream cylinders are usually subjected to more serious fluctuating forces under the influence of unsteady wake vortices. Also, the upstream cylinders normally experience larger mean drags than the downstream ones.
doi_str_mv 10.1016/j.jfluidstructs.2003.07.008
format article
fullrecord <record><control><sourceid>proquest_cross</sourceid><recordid>TN_cdi_proquest_miscellaneous_27886848</recordid><sourceformat>XML</sourceformat><sourcesystem>PC</sourcesystem><els_id>S088997460300118X</els_id><sourcerecordid>17603430</sourcerecordid><originalsourceid>FETCH-LOGICAL-c416t-57371eda92492953351f74040d41fa4784f99dddb1ed910271eb9679519a708a3</originalsourceid><addsrcrecordid>eNqNkctKAzEUhoMoWC_vEBDczXhymUmCK5FaBcGFug5pLpgynWgyo_TtnVo3ruzqwOH7fzjnQ-iCQE2AtFerehW6Mboy5NEOpaYArAZRA8gDNCOgmkq2lB6iGUipKiV4e4xOSlkBgOKMzNDiLmXrsU0-hGij74eCTe_w85DT-GY63I_rpc8Fp4BDGjO2my72bruJPbY5lYJDl77O0FEwXfHnv_MUvd7NX27vq8enxcPtzWNlOWmHqhFMEO-MolxR1TDWkCA4cHCcBMOF5EEp59xyghQBOsFL1QrVEGUESMNO0eWu9z2nj9GXQa9jsb7rTO_TWDQVUraSy39BIlpgnMEeIJWUCTqB1zvw5-rsg37PcW3yRhPQWx16pf_o0FsdGoSedEzp-S7tp-98Rp912b7behezt4N2Ke7V8w19OJsG</addsrcrecordid><sourcetype>Aggregation Database</sourcetype><iscdi>true</iscdi><recordtype>article</recordtype><pqid>17282372</pqid></control><display><type>article</type><title>Force coefficients and Strouhal numbers of four cylinders in cross flow</title><source>ScienceDirect Freedom Collection 2022-2024</source><creator>Lam, K ; Li, J.Y ; So, R.M.C</creator><creatorcontrib>Lam, K ; Li, J.Y ; So, R.M.C</creatorcontrib><description>This paper presents the measurements of force coefficients and Strouhal numbers (St) on four cylinders in a square configuration at subcritical Reynolds numbers (Re) using a piezo-electric load cell in a wind tunnel. Six spacing ratios ( L/D) varying from 1.69 to 3.83 and 13 angles of incidence α ranging from 0° to 180° at a 15° interval covering all orientations were investigated. With the help of a laser-induced fluorescence visualization technique, it is found that the variation of forces and Strouhal numbers with L/D are governed by three distinct flow patterns. They are: (a) free oscillations of shear layers and vortex formation at large L/D; (b) reattachment of shear layer or shielding flow for intermediate L/D and (c) narrow gap flows for small L/D. Two major causes for large fluctuating forces are discussed in this paper and the force results are compared with other measurements. It is concluded that the flow patterns, i.e., the development and the interferences of the free shear layers and the distribution of the wake vortices of the cylinders play a key role in the variation of the forces and shedding frequencies. Consequently, the downstream cylinders are usually subjected to more serious fluctuating forces under the influence of unsteady wake vortices. Also, the upstream cylinders normally experience larger mean drags than the downstream ones.</description><identifier>ISSN: 0889-9746</identifier><identifier>EISSN: 1095-8622</identifier><identifier>DOI: 10.1016/j.jfluidstructs.2003.07.008</identifier><language>eng</language><publisher>Elsevier Ltd</publisher><ispartof>Journal of fluids and structures, 2003-09, Vol.18 (3), p.305-324</ispartof><rights>2003 Elsevier Ltd</rights><lds50>peer_reviewed</lds50><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-c416t-57371eda92492953351f74040d41fa4784f99dddb1ed910271eb9679519a708a3</citedby><cites>FETCH-LOGICAL-c416t-57371eda92492953351f74040d41fa4784f99dddb1ed910271eb9679519a708a3</cites></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><link.rule.ids>315,786,790,27957,27958</link.rule.ids></links><search><creatorcontrib>Lam, K</creatorcontrib><creatorcontrib>Li, J.Y</creatorcontrib><creatorcontrib>So, R.M.C</creatorcontrib><title>Force coefficients and Strouhal numbers of four cylinders in cross flow</title><title>Journal of fluids and structures</title><description>This paper presents the measurements of force coefficients and Strouhal numbers (St) on four cylinders in a square configuration at subcritical Reynolds numbers (Re) using a piezo-electric load cell in a wind tunnel. Six spacing ratios ( L/D) varying from 1.69 to 3.83 and 13 angles of incidence α ranging from 0° to 180° at a 15° interval covering all orientations were investigated. With the help of a laser-induced fluorescence visualization technique, it is found that the variation of forces and Strouhal numbers with L/D are governed by three distinct flow patterns. They are: (a) free oscillations of shear layers and vortex formation at large L/D; (b) reattachment of shear layer or shielding flow for intermediate L/D and (c) narrow gap flows for small L/D. Two major causes for large fluctuating forces are discussed in this paper and the force results are compared with other measurements. It is concluded that the flow patterns, i.e., the development and the interferences of the free shear layers and the distribution of the wake vortices of the cylinders play a key role in the variation of the forces and shedding frequencies. Consequently, the downstream cylinders are usually subjected to more serious fluctuating forces under the influence of unsteady wake vortices. Also, the upstream cylinders normally experience larger mean drags than the downstream ones.</description><issn>0889-9746</issn><issn>1095-8622</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>2003</creationdate><recordtype>article</recordtype><recordid>eNqNkctKAzEUhoMoWC_vEBDczXhymUmCK5FaBcGFug5pLpgynWgyo_TtnVo3ruzqwOH7fzjnQ-iCQE2AtFerehW6Mboy5NEOpaYArAZRA8gDNCOgmkq2lB6iGUipKiV4e4xOSlkBgOKMzNDiLmXrsU0-hGij74eCTe_w85DT-GY63I_rpc8Fp4BDGjO2my72bruJPbY5lYJDl77O0FEwXfHnv_MUvd7NX27vq8enxcPtzWNlOWmHqhFMEO-MolxR1TDWkCA4cHCcBMOF5EEp59xyghQBOsFL1QrVEGUESMNO0eWu9z2nj9GXQa9jsb7rTO_TWDQVUraSy39BIlpgnMEeIJWUCTqB1zvw5-rsg37PcW3yRhPQWx16pf_o0FsdGoSedEzp-S7tp-98Rp912b7behezt4N2Ke7V8w19OJsG</recordid><startdate>20030901</startdate><enddate>20030901</enddate><creator>Lam, K</creator><creator>Li, J.Y</creator><creator>So, R.M.C</creator><general>Elsevier Ltd</general><scope>AAYXX</scope><scope>CITATION</scope><scope>F1W</scope><scope>H96</scope><scope>L.G</scope><scope>7TB</scope><scope>8FD</scope><scope>FR3</scope><scope>KR7</scope></search><sort><creationdate>20030901</creationdate><title>Force coefficients and Strouhal numbers of four cylinders in cross flow</title><author>Lam, K ; Li, J.Y ; So, R.M.C</author></sort><facets><frbrtype>5</frbrtype><frbrgroupid>cdi_FETCH-LOGICAL-c416t-57371eda92492953351f74040d41fa4784f99dddb1ed910271eb9679519a708a3</frbrgroupid><rsrctype>articles</rsrctype><prefilter>articles</prefilter><language>eng</language><creationdate>2003</creationdate><toplevel>peer_reviewed</toplevel><toplevel>online_resources</toplevel><creatorcontrib>Lam, K</creatorcontrib><creatorcontrib>Li, J.Y</creatorcontrib><creatorcontrib>So, R.M.C</creatorcontrib><collection>CrossRef</collection><collection>ASFA: Aquatic Sciences and Fisheries Abstracts</collection><collection>Aquatic Science &amp; Fisheries Abstracts (ASFA) 2: Ocean Technology, Policy &amp; Non-Living Resources</collection><collection>Aquatic Science &amp; Fisheries Abstracts (ASFA) Professional</collection><collection>Mechanical &amp; Transportation Engineering Abstracts</collection><collection>Technology Research Database</collection><collection>Engineering Research Database</collection><collection>Civil Engineering Abstracts</collection><jtitle>Journal of fluids and structures</jtitle></facets><delivery><delcategory>Remote Search Resource</delcategory><fulltext>fulltext</fulltext></delivery><addata><au>Lam, K</au><au>Li, J.Y</au><au>So, R.M.C</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>Force coefficients and Strouhal numbers of four cylinders in cross flow</atitle><jtitle>Journal of fluids and structures</jtitle><date>2003-09-01</date><risdate>2003</risdate><volume>18</volume><issue>3</issue><spage>305</spage><epage>324</epage><pages>305-324</pages><issn>0889-9746</issn><eissn>1095-8622</eissn><notes>ObjectType-Article-1</notes><notes>SourceType-Scholarly Journals-1</notes><notes>ObjectType-Feature-2</notes><notes>content type line 23</notes><notes>ObjectType-Article-2</notes><notes>ObjectType-Feature-1</notes><abstract>This paper presents the measurements of force coefficients and Strouhal numbers (St) on four cylinders in a square configuration at subcritical Reynolds numbers (Re) using a piezo-electric load cell in a wind tunnel. Six spacing ratios ( L/D) varying from 1.69 to 3.83 and 13 angles of incidence α ranging from 0° to 180° at a 15° interval covering all orientations were investigated. With the help of a laser-induced fluorescence visualization technique, it is found that the variation of forces and Strouhal numbers with L/D are governed by three distinct flow patterns. They are: (a) free oscillations of shear layers and vortex formation at large L/D; (b) reattachment of shear layer or shielding flow for intermediate L/D and (c) narrow gap flows for small L/D. Two major causes for large fluctuating forces are discussed in this paper and the force results are compared with other measurements. It is concluded that the flow patterns, i.e., the development and the interferences of the free shear layers and the distribution of the wake vortices of the cylinders play a key role in the variation of the forces and shedding frequencies. Consequently, the downstream cylinders are usually subjected to more serious fluctuating forces under the influence of unsteady wake vortices. Also, the upstream cylinders normally experience larger mean drags than the downstream ones.</abstract><pub>Elsevier Ltd</pub><doi>10.1016/j.jfluidstructs.2003.07.008</doi><tpages>20</tpages></addata></record>
fulltext fulltext
identifier ISSN: 0889-9746
ispartof Journal of fluids and structures, 2003-09, Vol.18 (3), p.305-324
issn 0889-9746
1095-8622
language eng
recordid cdi_proquest_miscellaneous_27886848
source ScienceDirect Freedom Collection 2022-2024
title Force coefficients and Strouhal numbers of four cylinders in cross flow
url http://sfxeu10.hosted.exlibrisgroup.com/loughborough?ctx_ver=Z39.88-2004&ctx_enc=info:ofi/enc:UTF-8&ctx_tim=2024-09-22T21%3A14%3A34IST&url_ver=Z39.88-2004&url_ctx_fmt=infofi/fmt:kev:mtx:ctx&rfr_id=info:sid/primo.exlibrisgroup.com:primo3-Article-proquest_cross&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.genre=article&rft.atitle=Force%20coefficients%20and%20Strouhal%20numbers%20of%20four%20cylinders%20in%20cross%20flow&rft.jtitle=Journal%20of%20fluids%20and%20structures&rft.au=Lam,%20K&rft.date=2003-09-01&rft.volume=18&rft.issue=3&rft.spage=305&rft.epage=324&rft.pages=305-324&rft.issn=0889-9746&rft.eissn=1095-8622&rft_id=info:doi/10.1016/j.jfluidstructs.2003.07.008&rft_dat=%3Cproquest_cross%3E17603430%3C/proquest_cross%3E%3Cgrp_id%3Ecdi_FETCH-LOGICAL-c416t-57371eda92492953351f74040d41fa4784f99dddb1ed910271eb9679519a708a3%3C/grp_id%3E%3Coa%3E%3C/oa%3E%3Curl%3E%3C/url%3E&rft_id=info:oai/&rft_pqid=17282372&rft_id=info:pmid/&rfr_iscdi=true