{"id":{"repo_id":"vt","oai_identifier":"oai:vtechworks.lib.vt.edu:10919/45984"},"canonical_url":"https://search.dev.ndltd.org/etd/vt/oai:vtechworks.lib.vt.edu:10919/45984","repository":{"repo_id":"vt","name":"Virginia Tech","base_url":"https://vtechworks.lib.vt.edu/oai/request"},"display":{"title":"The correlation of randomness with high tip losses in an axial flow fan stage","abstract":"The results of a test program incorporating a dual hot wire aspirating probe to radially survey the by-pass duct downstream of an axial flow fan stage are presented. The probe measures time resolved total temperature and total pressure from which isentropic efficiency is calculated. The objective was to provide time resolved data to further the understanding of the flow and aid in determining the source of high losses located near the rotor tip. A technique for quantifying randomness of an unsteady flow is developed, and the randomness of the surveyed flow is shown to correlate with the losses. A new method of ensemble averaging instantaneous data is presented which produces an identifiable blade passage profile even in a random flowfield where traditional techniques often fail. Time averages of the aspirating probe data are shown to agree with conventional steady-state measurements within the experimental uncertainties. Unsteady features seen in the data are compared to similar features noted in the literature, and contour plots of the ensemble averaged data and unsteady fluctuations are presented.","abstract_html":"The results of a test program incorporating a dual hot wire aspirating probe to radially survey the by-pass duct downstream of an axial flow fan stage are presented. The probe measures time resolved total temperature and total pressure from which isentropic efficiency is calculated. The objective was to provide time resolved data to further the understanding of the flow and aid in determining the source of high losses located near the rotor tip. A technique for quantifying randomness of an unsteady flow is developed, and the randomness of the surveyed flow is shown to correlate with the losses. A new method of ensemble averaging instantaneous data is presented which produces an identifiable blade passage profile even in a random flowfield where traditional techniques often fail. Time averages of the aspirating probe data are shown to agree with conventional steady-state measurements within the experimental uncertainties. Unsteady features seen in the data are compared to similar features noted in the literature, and contour plots of the ensemble averaged data and unsteady fluctuations are presented.","abstract_has_math":false,"creators":["Alday, John Hane"],"institution":"Virginia Tech","degree_name":"Master of Science","degree_level":"masters","degree_discipline":"Mechanical Engineering","degree_department":"Mechanical Engineering","school":null,"contributors":[],"advisors":[],"committee_chairs":["Ng, Wing Fai"],"committee_members":["Moses, Hal L.","Vick, Brian L."],"year":1991,"date_issued":"1991-04-19","date_published":"1991-04-19","updated_at":"2026-07-22T22:19:12Z","subjects":[],"languages":["en"],"rights":["In Copyright"],"rights_urls":["http://rightsstatements.org/vocab/InC/1.0/"],"identifier_entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["etd-11242009-020017"],"render_values":[{"text":"etd-11242009-020017","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/10919/45984","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.committeechair","label":"Committee Chair","values":["Ng, Wing Fai"]},{"key":"dc:contributor.committeemember","label":"Committee Member","values":["Moses, Hal L.","Vick, Brian L."]},{"key":"dc:contributor.department","label":"Department","values":["Mechanical Engineering"]},{"key":"dc:creator","label":"Author","values":["Alday, John Hane"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2014-03-14T21:50:31Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2014-03-14T21:50:31Z","2009-11-24"]},{"key":"dc:date.issued","label":"Date","values":["1991-04-19"]},{"key":"dc:publisher","label":"Institution","values":["Virginia Tech"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"dc:type.dcmitype","label":"Dc Type Dcmitype","values":["Text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Mechanical Engineering"]},{"key":"thesis:degree_level","label":"Degree Level","values":["masters"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Virginia Polytechnic Institute and State University"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en"]},{"key":"dc:rights","label":"Dc Rights","values":["In Copyright"]},{"key":"dc:rights.uri","label":"Rights URI","values":["http://rightsstatements.org/vocab/InC/1.0/"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["etd-11242009-020017"]},{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/10919/45984"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["The results of a test program incorporating a dual hot wire aspirating probe to radially survey the by-pass duct downstream of an axial flow fan stage are presented. The probe measures time resolved total temperature and total pressure from which isentropic efficiency is calculated. The objective was to provide time resolved data to further the understanding of the flow and aid in determining the source of high losses located near the rotor tip. A technique for quantifying randomness of an unsteady flow is developed, and the randomness of the surveyed flow is shown to correlate with the losses. A new method of ensemble averaging instantaneous data is presented which produces an identifiable blade passage profile even in a random flowfield where traditional techniques often fail. Time averages of the aspirating probe data are shown to agree with conventional steady-state measurements within the experimental uncertainties. Unsteady features seen in the data are compared to similar features noted in the literature, and contour plots of the ensemble averaged data and unsteady fluctuations are presented."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["Master of Science"]},{"key":"dc:format.medium","label":"Dc Format Medium","values":["BTD"]},{"key":"dc:format.mimetype","label":"Dc Format Mimetype","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["The correlation of randomness with high tip losses in an axial flow fan stage"]}]}],"canonical_facts":{"dc:contributor.committeechair":["Ng, Wing Fai"],"dc:contributor.committeemember":["Moses, Hal L.","Vick, Brian L."],"dc:contributor.department":["Mechanical Engineering"],"dc:creator":["Alday, John Hane"],"dc:date.accessioned":["2014-03-14T21:50:31Z"],"dc:date.available":["2014-03-14T21:50:31Z","2009-11-24"],"dc:date.issued":["1991-04-19"],"dc:description.abstract":["The results of a test program incorporating a dual hot wire aspirating probe to radially survey the by-pass duct downstream of an axial flow fan stage are presented. The probe measures time resolved total temperature and total pressure from which isentropic efficiency is calculated. The objective was to provide time resolved data to further the understanding of the flow and aid in determining the source of high losses located near the rotor tip. A technique for quantifying randomness of an unsteady flow is developed, and the randomness of the surveyed flow is shown to correlate with the losses. A new method of ensemble averaging instantaneous data is presented which produces an identifiable blade passage profile even in a random flowfield where traditional techniques often fail. Time averages of the aspirating probe data are shown to agree with conventional steady-state measurements within the experimental uncertainties. Unsteady features seen in the data are compared to similar features noted in the literature, and contour plots of the ensemble averaged data and unsteady fluctuations are presented."],"dc:description.degree":["Master of Science"],"dc:format.medium":["BTD"],"dc:format.mimetype":["application/pdf"],"dc:identifier.other":["etd-11242009-020017"],"dc:identifier.uri":["http://hdl.handle.net/10919/45984"],"dc:language.iso":["en"],"dc:publisher":["Virginia Tech"],"dc:rights":["In Copyright"],"dc:rights.uri":["http://rightsstatements.org/vocab/InC/1.0/"],"dc:title":["The correlation of randomness with high tip losses in an axial flow fan stage"],"dc:type":["Thesis"],"dc:type.dcmitype":["Text"],"thesis:degree_discipline":["Mechanical Engineering"],"thesis:degree_level":["masters"],"thesis:degree_name":["Master of Science"],"thesis:institution_name":["Virginia Polytechnic Institute and State University"]},"updated_at":"2026-07-22T22:19:12Z"}