{"id":{"repo_id":"washington","oai_identifier":"oai:digital.lib.washington.edu:1773/22851"},"canonical_url":"https://search.dev.ndltd.org/etd/washington/oai:digital.lib.washington.edu:1773/22851","repository":{"repo_id":"washington","name":"University of Washington","base_url":"https://digital.lib.washington.edu/server/oai/request"},"display":{"title":"The Effect of Persistent Vortices on Boundary Layer Behavior in Turbulent Flow along a Kelvin-Stuart Cat's Eyes Wavy Wall","abstract":"The vortex persistence theory predicts that the addition of a sufficiently strong, stationary vortex near a wall will reduce the wall fluxes in turbulent flows. To test the theory flow visualization and hot-wire experiments in a water tunnel at moderate Reynolds number reveal that a persistent vortex will relaminarize the boundary layer along wavy even in the presence of freestream turbulence. This result is consistent with Dawson [7] who found similar boundary layer behavior using a von Karman separatrix shaped wavy wall, and Balle [2], who's results showed laminar wall heat fluxes under stationary vortices using the von Karman wavy wall. Based on Dawson's flow visualization, and following Balle's analogy, the separatrix of a Kelvin-Stuart Cat's Eyes flow pattern was replaced with a solid wavy wall to stabilize the vortices shed by an array of half-delta vortex generators just upstream of the leading edge of the wavy wall. The correct angle of the array allows for persistent vortices to traverse along the grooves of the wavy wall, and displacing the array even slightly yields different turbulent fluxes. The present flow visualization and hot-wire anemometry results suggest that using the cat's eyes wavy wall gives better relaminarization properties than the von Karman shaped wavy wall, which can have many real world applications.","abstract_html":"The vortex persistence theory predicts that the addition of a sufficiently strong, stationary vortex near a wall will reduce the wall fluxes in turbulent flows. To test the theory flow visualization and hot-wire experiments in a water tunnel at moderate Reynolds number reveal that a persistent vortex will relaminarize the boundary layer along wavy even in the presence of freestream turbulence. This result is consistent with Dawson [7] who found similar boundary layer behavior using a von Karman separatrix shaped wavy wall, and Balle [2], who's results showed laminar wall heat fluxes under stationary vortices using the von Karman wavy wall. Based on Dawson's flow visualization, and following Balle's analogy, the separatrix of a Kelvin-Stuart Cat's Eyes flow pattern was replaced with a solid wavy wall to stabilize the vortices shed by an array of half-delta vortex generators just upstream of the leading edge of the wavy wall. The correct angle of the array allows for persistent vortices to traverse along the grooves of the wavy wall, and displacing the array even slightly yields different turbulent fluxes. The present flow visualization and hot-wire anemometry results suggest that using the cat's eyes wavy wall gives better relaminarization properties than the von Karman shaped wavy wall, which can have many real world applications.","abstract_has_math":false,"creators":["Mehmedagic, Amir"],"institution":null,"degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Breidenthal, Robert"],"committee_chairs":[],"committee_members":[],"year":2013,"date_issued":"2013-07-23","date_published":"2013-07-23","updated_at":"2026-07-24T05:58:20Z","subjects":["Kelvin's Cat's Eyes; Laminar Flow; Persistence Theory; Relaminarization; Turbulence; Wavy Wall"],"languages":["en_US"],"rights":["Copyright is held by the individual authors."],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/1773/22851","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Breidenthal, Robert"]},{"key":"dc:creator","label":"Author","values":["Mehmedagic, Amir"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2013-07-23T18:30:47Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2013-07-23T18:30:47Z"]},{"key":"dc:date.issued","label":"Date","values":["2013-07-23"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Kelvin's Cat's Eyes; Laminar Flow; Persistence Theory; Relaminarization; Turbulence; Wavy Wall"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en_US"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright is held by the individual authors."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["Mehmedagic_washington_0250O_11367.pdf"]},{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/1773/22851"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Thesis (Master's)--University of Washington, 2013"]},{"key":"dc:description.abstract","label":"Abstract","values":["The vortex persistence theory predicts that the addition of a sufficiently strong, stationary vortex near a wall will reduce the wall fluxes in turbulent flows. To test the theory flow visualization and hot-wire experiments in a water tunnel at moderate Reynolds number reveal that a persistent vortex will relaminarize the boundary layer along wavy even in the presence of freestream turbulence. This result is consistent with Dawson [7] who found similar boundary layer behavior using a von Karman separatrix shaped wavy wall, and Balle [2], who's results showed laminar wall heat fluxes under stationary vortices using the von Karman wavy wall. Based on Dawson's flow visualization, and following Balle's analogy, the separatrix of a Kelvin-Stuart Cat's Eyes flow pattern was replaced with a solid wavy wall to stabilize the vortices shed by an array of half-delta vortex generators just upstream of the leading edge of the wavy wall. The correct angle of the array allows for persistent vortices to traverse along the grooves of the wavy wall, and displacing the array even slightly yields different turbulent fluxes. The present flow visualization and hot-wire anemometry results suggest that using the cat's eyes wavy wall gives better relaminarization properties than the von Karman shaped wavy wall, which can have many real world applications."]},{"key":"dc:format.mimetype","label":"Dc Format Mimetype","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["The Effect of Persistent Vortices on Boundary Layer Behavior in Turbulent Flow along a Kelvin-Stuart Cat's Eyes Wavy Wall"]}]}],"canonical_facts":{"dc:contributor.advisor":["Breidenthal, Robert"],"dc:creator":["Mehmedagic, Amir"],"dc:date.accessioned":["2013-07-23T18:30:47Z"],"dc:date.available":["2013-07-23T18:30:47Z"],"dc:date.issued":["2013-07-23"],"dc:description":["Thesis (Master's)--University of Washington, 2013"],"dc:description.abstract":["The vortex persistence theory predicts that the addition of a sufficiently strong, stationary vortex near a wall will reduce the wall fluxes in turbulent flows. To test the theory flow visualization and hot-wire experiments in a water tunnel at moderate Reynolds number reveal that a persistent vortex will relaminarize the boundary layer along wavy even in the presence of freestream turbulence. This result is consistent with Dawson [7] who found similar boundary layer behavior using a von Karman separatrix shaped wavy wall, and Balle [2], who's results showed laminar wall heat fluxes under stationary vortices using the von Karman wavy wall. Based on Dawson's flow visualization, and following Balle's analogy, the separatrix of a Kelvin-Stuart Cat's Eyes flow pattern was replaced with a solid wavy wall to stabilize the vortices shed by an array of half-delta vortex generators just upstream of the leading edge of the wavy wall. The correct angle of the array allows for persistent vortices to traverse along the grooves of the wavy wall, and displacing the array even slightly yields different turbulent fluxes. The present flow visualization and hot-wire anemometry results suggest that using the cat's eyes wavy wall gives better relaminarization properties than the von Karman shaped wavy wall, which can have many real world applications."],"dc:format.mimetype":["application/pdf"],"dc:identifier.other":["Mehmedagic_washington_0250O_11367.pdf"],"dc:identifier.uri":["http://hdl.handle.net/1773/22851"],"dc:language.iso":["en_US"],"dc:rights":["Copyright is held by the individual authors."],"dc:subject":["Kelvin's Cat's Eyes; Laminar Flow; Persistence Theory; Relaminarization; Turbulence; Wavy Wall"],"dc:title":["The Effect of Persistent Vortices on Boundary Layer Behavior in Turbulent Flow along a Kelvin-Stuart Cat's Eyes Wavy Wall"],"dc:type":["Thesis"]},"updated_at":"2026-07-24T05:58:20Z"}