Reduced fan noise radiation from a supersonic inlet

Simple item page
dc.contributor.authorDetwiler, Kevin P.en
dc.contributor.committeechairNg, Wing Faien
dc.contributor.committeememberBurdisso, Ricardo A.en
dc.contributor.committeememberLeonard, Robert G.en
dc.contributor.departmentMechanical Engineeringen
dc.date.accessioned2014-03-14T21:46:20Zen
dc.date.adate2009-09-19en
dc.date.available2014-03-14T21:46:20Zen
dc.date.issued1993-04-15en
dc.date.rdate2009-09-19en
dc.date.sdate2009-09-19en
dc.description.abstractA series of experiments was conducted to evaluate the aerodynamic and acoustic performance of a supersonic inlet with a modified auxiliary door geometry. A 1/14 scale model of an axisymmetric, mixed-compression, supersonic inlet designed for civil transportation was used in conjunction with a 10.4cm (4.1 in.) turbofan engine simulator to test a new inlet door geometry designed to reduce flow distortion and noise radiation. The new door geometry uses door passages with increased circumferential span to improve the distribution of the flow entering through the doors. In addition, the new design employs sonic flow velocity at the inlet throat and a converging flow passage in the auxiliary doors to attenuate propagating fan noise through the choking effect. To provide a basis for comparison, a baseline door geometry representative of current designs was also tested. The experiments were conducted at simulated aircraft takeoff engine speeds under static conditions. Steady-state measurements of the inlet flow field were made along with far field acoustic measurements of the fan noise. The results show the new door geometry is successful in reducing circumferential flow distortion at the fan entrance by a factor of 2.3 compared to the baseline configuration. In addition, far field radiation of the blade passing frequency tone and overall noise is reduced by an average of 4dB(SPL) in the forward and aft sectors (0° to 110° from the inlet axis). As a compromise for the distortion and acoustic improvements, the overall inlet total pressure recovery is reduced by approximately 2% with the new auxiliary doors.en
dc.description.degreeMaster of Scienceen
dc.format.extentx, 87 leavesen
dc.format.mediumBTDen
dc.format.mimetypeapplication/pdfen
dc.identifier.otheretd-09192009-040457en
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-09192009-040457/en
dc.identifier.urihttp://hdl.handle.net/10919/44869en
dc.language.isoenen
dc.publisherVirginia Techen
dc.relation.haspartLD5655.V855_1993.D478.pdfen
dc.relation.isformatofOCLC# 29040721en
dc.rightsIn Copyrighten
dc.rights.urihttp://rightsstatements.org/vocab/InC/1.0/en
dc.subject.lccLD5655.V855 1993.D478en
dc.subject.lcshAerodynamic noiseen
dc.subject.lcshAerodynamics, Supersonicen
dc.subject.lcshAirplanes -- Turbofan enginesen
dc.titleReduced fan noise radiation from a supersonic inleten
dc.typeThesisen
dc.type.dcmitypeTexten
thesis.degree.disciplineMechanical Engineeringen
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen
thesis.degree.levelmastersen
thesis.degree.nameMaster of Scienceen

Files

Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
LD5655.V855_1993.D478.pdf
Size:
8.44 MB
Format:
Adobe Portable Document Format
Description:
Download

Collections

Masters Theses