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dc.contributor.authorBloch, Gregory S.en_US
dc.date.accessioned2014-03-14T21:12:03Z
dc.date.available2014-03-14T21:12:03Z
dc.date.issued1996-07-06en_US
dc.identifier.otheretd-06062008-151220en_US
dc.identifier.urihttp://hdl.handle.net/10919/37993
dc.description.abstractLoss models used in compression system performance prediction codes are often developed from the study of two-dimensional cascades. The physical mechanisms that affect the flow in supersonic compressor cascades have been reviewed, including the changes in shock geometry that will occur with back pressure for both started and unstarted operation. Compressible fluid mechanics has been applied to the known shock geometry to obtain a physics-based engineering shock loss model that is applicable over the entire supersonic operating range of the cascade. Predictions from the present method have been compared to measurements and Navier-Stokes analyses of the L030-4 and L030-6 cascades, and very good agreement was demonstrated for unstarted operation. Son1e of the started comparisons exhibited good agreement, while others did not. A clear improvement has been demonstrated over previously published shock loss models, both in the accuracy of the predictions and in the range of applicability. The dramatic increase in overall loss with increasing inlet flow angle is shown to be primarily the result of increased shock loss, and much of this increase is caused by the detached bow shock. For a given Mach number, the viscous profile loss is nearly constant over the entire un started operating range of the cascade, unless a shock-induced boundary layer separation occurs near stall. Shock loss is much more sensitive to inlet Mach number than is viscous profile loss. The present shock loss model has been used as the basis of an overall loss prediction method by adding a constant value, representative of the viscous profile loss, to the predicted shock loss characteristics. The overall loss characteristics obtained in this manner showed good agreement with the experimental values over the most useful operating range of the cascade.en_US
dc.format.mediumBTDen_US
dc.publisherVirginia Techen_US
dc.relation.haspartLD5655.V856_1996.B563.pdfen_US
dc.subjectcompressoren_US
dc.subjectcascadeen_US
dc.subjectshocken_US
dc.subjectlossen_US
dc.subjectmodelen_US
dc.subject.lccLD5655.V856 1996.B563en_US
dc.titleFlow losses in supersonic compressor cascadesen_US
dc.typeDissertationen_US
dc.contributor.departmentMechanical Engineeringen_US
dc.description.degreePh. D.en_US
thesis.degree.namePh. D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen_US
thesis.degree.disciplineMechanical Engineeringen_US
dc.contributor.committeechairO'Brien, Walter F. Jr.en_US
dc.contributor.committeememberLaw, C. Herberten_US
dc.contributor.committeememberDancey, Clinton L.en_US
dc.contributor.committeememberCopenhaver, William W.en_US
dc.contributor.committeememberMoore, Johnen_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-06062008-151220/en_US
dc.date.sdate2008-06-06en_US
dc.date.rdate2008-06-06
dc.date.adate2008-06-06en_US


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