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dc.contributor.advisorHoward, Richard M.
dc.contributor.authorGwilliam, David J., Jr.
dc.dateDecember 1989
dc.date.accessioned2013-01-23T22:10:50Z
dc.date.available2013-01-23T22:10:50Z
dc.date.issued1989-12
dc.identifier.urihttp://hdl.handle.net/10945/27259
dc.description.abstractAn experimental investigation of the separating boundary layer of a wing subjected to periodic turbulent disturbances was conducted. Turbulence pulses were generated by a non-thrusting spin­ning rod placed upstream of the test airfoil at the reduced frequencies of .09 and .47. Time-varying velocity measurements were made at various heights above the 70% chord location at 12 degrees angle of attack (nearly separated flow) and 22 degrees angle of attack (fully separated flow). Split-film anemometry was used to determine flow speed and direction. The flow responses were compared to the quasi-steady state of undisturbed separated flow. Variation of reduced frequency had a dramatic influence on the effects which the periodic disturbance had on the flow response. At a reduced frequency of .47 the periodic disturbance had no noticeable influence. Imposition of periodic disturbance of the same reduced frequency on attached flow near separation (12 degrees angle of attack) once again caused no apparent destabilizing effects. The lack of sensi­tivity of the separated boundary layer to the pulses generated at the higher reduced frequency of .47 apparently resulted from its inability to resolve turbulent pulses from one another. Imposition at 22 degrees angle of attack of a pulse at the reduced frequency of .09, however, first stabilized the flow, then greatly intensified the original separation before allowing the flow to return to its undisturbed separated state.
dc.description.urihttp://archive.org/details/separatingbounda1094527259
dc.format.extent130 p.en_US
dc.language.isoen_US
dc.publisherMonterey, California. Naval Postgraduate Schoolen_US
dc.rightsThis publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States.
dc.titleSeparating boundary layer response to an unsteady turbulent environmenten_US
dc.typeThesisen_US
dc.contributor.secondreaderNetzer, David W.
dc.contributor.corporateNaval Postgraduate School (U.S.)
dc.contributor.departmentAeronautics and Astronautics
dc.subject.authorSeparateden_US
dc.subject.authorBoundary layer response to disturbanceen_US
dc.subject.authorUnsteady aerodynamicsen_US
dc.description.serviceLieutenant, United States Navy
etd.thesisdegree.nameM.S. in Engineering Scienceen_US
etd.thesisdegree.levelMastersen_US
etd.thesisdegree.disciplineEngineering Scienceen_US
etd.thesisdegree.grantorNaval Postgraduate Schoolen_US
dc.description.distributionstatementApproved for public release; distribution is unlimited.


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