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dc.contributor.authorPatrick, Wilfred Vinoden_US
dc.date.accessioned2014-03-14T20:39:20Z
dc.date.available2014-03-14T20:39:20Z
dc.date.issued2005-04-25en_US
dc.identifier.otheretd-06042005-145209en_US
dc.identifier.urihttp://hdl.handle.net/10919/33415
dc.description.abstractTime-accurate calculations are used to investigate the three-dimensional flow structure and understand its influence on the heat transfer in a channel with concave indentations on one wall. A dimple depth to channel height ratio of 0.4 and dimple depth to imprint diameter ratio of 0.2 is used in the calculations. The Reynolds number (based on channel height) varies from Re = 25 in the laminar regime to Re = 2000 in the early turbulent regime. Fully developed flow and heat transfer conditions were assumed and a constant heat flux boundary condition was applied to the walls of the channel. In the laminar regime, the flow and heat transfer characteristics are dominated by the recirculation zones in the dimple with resulting augmentation ratios below unity. Flow transition is found to occur between Re = 1020 and 1130 after which both heat transfer and friction augmentation increase to values of 3.22 and 2.75, respectively, at Re = 2000. The presence of large scale vortical structures ejected from the dimple cavity dominate all aspects of the flow and heat transfer, not only on the dimpled surface but also on the smooth wall. In all cases the thermal efficiency using dimples was found to be significantly larger than other heat transfer augmentation techniques currently employed.en_US
dc.publisherVirginia Techen_US
dc.relation.haspartetd_thesis.pdfen_US
dc.rightsI hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to Virginia Tech or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.en_US
dc.subjectFlow structureen_US
dc.subjectTransitionen_US
dc.subjectDNSen_US
dc.subjectConcavitiesen_US
dc.subjectDimplesen_US
dc.titleComputations of Flow Structures and Heat Transfer in a Dimpled Channel at Low to Moderate Reynolds Numberen_US
dc.typeThesisen_US
dc.contributor.departmentMechanical Engineeringen_US
dc.description.degreeMaster of Scienceen_US
thesis.degree.nameMaster of Scienceen_US
thesis.degree.levelmastersen_US
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen_US
thesis.degree.disciplineMechanical Engineeringen_US
dc.contributor.committeechairTafti, Danesh K.en_US
dc.contributor.committeememberRagab, Saad A.en_US
dc.contributor.committeememberVick, Brian L.en_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-06042005-145209/en_US
dc.date.sdate2005-06-04en_US
dc.date.rdate2005-08-23
dc.date.adate2005-08-23en_US


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