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dc.contributor.authorHussain, Mian M.en_US
dc.date.accessioned2014-03-14T21:26:36Z
dc.date.available2014-03-14T21:26:36Z
dc.date.issued2004-12-15en_US
dc.identifier.otheretd-01062005-132239en_US
dc.identifier.urihttp://hdl.handle.net/10919/40538
dc.description.abstractActive pneumatic flow control methods as applied to aerospace applications have shown noteworthy improvements in lift compared to traditional means. The General Aviation Circulation Control (GACC) concept currently under investigation at NASAâ s Langley Research Center (LaRC) is an attempt at addressing some of the fundamental obstacles related to the successful development and implementation of such techniques. The primary focus of research in the field of high lift pneumatic devices is to investigate ways of obtaining significant improvements in the lift coefficient without resorting to moving surfaces. Though it has been demonstrated that the lift coefficient can be amplified in a variety of ways, the chosen method for the current work is via enhanced circulation stemming from a trailing edge Coanda jet. A secondary objective is to reduce the amount energy expenditure used in these pneumatic techniques by implementing time-variant flow. This paper describes experimental observations of the flow behavior at the trailing edge of a modified water tunnel based supercritical airfoil model that exploits both steady and pulsed Coanda driven circulation control. A total of 10 sets of data, excluding a baseline case of no Coanda jet, were sampled with five cases each for steady and pulsed flow, the latter at a reduced frequency, f+, of 1. Two cases of equal momentum coefficient but with varying forced frequencies were isolated for further study in an attempt to accurately compare the resultant flow dynamics of each method. All measurements were taken at a zero-lift angle of attack by means of a non-invasive time accurate flow visualization technique (DPIV). Vorticity behavior was investigated using Tecplot® and a MATLAB® program was developed to quantify the Strouhal Number of time-averaged velocity fluctuations moving aft of the Coanda surface for each case.en_US
dc.publisherVirginia Techen_US
dc.relation.haspartHussain_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.subjectVortex Formationen_US
dc.subjectJet Pulsationen_US
dc.subjectFlow Visualizationen_US
dc.subjectFlow Controlen_US
dc.subjectCoanda Effecten_US
dc.subjectDPIVen_US
dc.subjectCirculation Control Wing (CCW)en_US
dc.titleTime-Resolved Analysis of Circulation Control over Supercritical Airfoil using Digital Particle Image Velocimetry (DPIV)en_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.committeechairVlachos, Pavlos P.en_US
dc.contributor.committeememberTelionis, Demetri P.en_US
dc.contributor.committeememberDancey, Clinton L.en_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-01062005-132239/en_US
dc.date.sdate2005-01-06en_US
dc.date.rdate2013-04-30
dc.date.adate2005-01-07en_US


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