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dc.contributor.authorLeitch, Thomas A.en_US
dc.date.accessioned2014-03-14T20:21:59Z
dc.date.available2014-03-14T20:21:59Z
dc.date.issued1997-01-16en_US
dc.identifier.otheretd-4241161974360en_US
dc.identifier.urihttp://hdl.handle.net/10919/30527
dc.description.abstractAn aeroacoustic investigation was performed to assess the effects of adding mass flow at the trailing edges of four stators upstream of an aircraft engine simulator. By using trailing edge blowing to minimize the shed wakes of the stators, the flow into the rotor was made more uniform. In these experiments a reduced number of stators (four) was used in a 1/14 scale model inlet which was coupled to a 4.1 in (10.4 cm) turbofan engine simulator with 18 rotors and 26 downstream stators. This study is a preliminary step toward a more in depth investigation of using trailing edge blowing to reduce unsteady rotor-stator interaction. Steady-state measurements of the aerodynamic flow field and acoustic far field were made in order to evaluate the aeroacoustic performance at three simulator speeds: 40%, 60%, and 88% of the design speed. The lowest test speed of 40% design speed showed the most dramatic reduction in radiated noise. Noise reductions as large as 8.9 dB in the blade passing tone were recorded at 40% design speed, while a tone reduction of 5.5 dB was recorded at 60% design speed. At 88% design speed a maximum tone reduction of 2.6 dB was recorded. In addition, trailing edge blowing reduced the overall sound pressure level in every case. For both the 40% design speed and the 60% design speed, the fan face distortion was significantly reduced due to the trailing edge blowing. The addition of trailing edge blowing from the four upstream stators did not change the total pressure ratio, and the mass flow added by the blowing was approximately 1%. The results of these experiments clearly demonstrate that blowing from the trailing edges of the stators is effective in reducing unsteady rotor-stator interaction and the subsequent forward radiated noise.en_US
dc.publisherVirginia Techen_US
dc.relation.haspartetd.PDFen_US
dc.rightsI hereby grant to Virginia Tech or its agents the right to archive and to make available my thesis or dissertation in whole or in part in the University Libraries in all forms of media, now or hereafter known. I retain all proprietary rights, such as patent rights. I also retain the right to use in future works (such as articles or books) all or part of this thesis or dissertation.en_US
dc.subjectTrailing Edge Blowingen_US
dc.subjectAeroacousticen_US
dc.subjectNoiseen_US
dc.subjectTurbomachineryen_US
dc.titleReduction of Unsteady Rotor-Stator Interaction Using Trailing Edge Blowingen_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.committeechairNg, Wing Faien_US
dc.contributor.committeememberBurdisso, Ricardo A.en_US
dc.contributor.committeememberDancey, Clinton L.en_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-4241161974360/en_US
dc.date.sdate1998-07-24en_US
dc.date.rdate1998-01-16
dc.date.adate1997-01-16en_US


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