{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/69742"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/69742","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Viscoelastic Fluid Flow Past a Submerged Spheroidal Body (Birefringence, Free Energy)","abstract":"A stable and time-efficient numerical algorithm has been developed to study the problem of homogeneous axisymmetric flow of a third order fluid past a spheriodal body. The numerical solution was shown to agree well with existing analytical solutions for several limiting cases (such as flow past a sphere), and was used to investigate the effects of the (a) body shape, (b) free stream conditions, and (c) fluid elasticity on the local velocity and stress fields. The results of this study indicate that while a submerged spheroid gave rise to strong and highly localized stress fields, an immersed sphere created a stress field of moderate strength extending over larger distances. Also, it was found that the different free stream velocity fields, which included uniform flow, simple extensional flow and converging flow, resulted in different stress fields the strongest of which was produced by the extensional flow. Finally, it was found that the elasticity of the fluid had a profound effect on the local stresses. In some cases, the fore-aft symmetry of the stress field was lost, in others circulatory flow regions were produced downstream, and in all cases the magnitude of the stress tensor was increased as a result of increasing the fluid elasticity.","abstract_html":"A stable and time-efficient numerical algorithm has been developed to study the problem of homogeneous axisymmetric flow of a third order fluid past a spheriodal body. The numerical solution was shown to agree well with existing analytical solutions for several limiting cases (such as flow past a sphere), and was used to investigate the effects of the (a) body shape, (b) free stream conditions, and (c) fluid elasticity on the local velocity and stress fields. The results of this study indicate that while a submerged spheroid gave rise to strong and highly localized stress fields, an immersed sphere created a stress field of moderate strength extending over larger distances. Also, it was found that the different free stream velocity fields, which included uniform flow, simple extensional flow and converging flow, resulted in different stress fields the strongest of which was produced by the extensional flow. Finally, it was found that the elasticity of the fluid had a profound effect on the local stresses. In some cases, the fore-aft symmetry of the stress field was lost, in others circulatory flow regions were produced downstream, and in all cases the magnitude of the stress tensor was increased as a result of increasing the fluid elasticity.","abstract_has_math":false,"creators":["Dairanieh, Issam Salah"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Chemical Engineering","degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2014,"date_issued":"2014-12-15T19:54:15Z","date_published":"2014-12-15T19:54:15Z","updated_at":"2026-07-22T22:26:01Z","subjects":["Engineering, Chemical"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["(UMI)AAI8502123"],"render_values":[{"text":"(UMI)AAI8502123","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/69742","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Dairanieh, Issam Salah"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2014-12-15T19:54:15Z","10000-01-01","1984"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Chemical Engineering"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph.D."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Engineering, Chemical"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/2142/69742","(UMI)AAI8502123"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["A stable and time-efficient numerical algorithm has been developed to study the problem of homogeneous axisymmetric flow of a third order fluid past a spheriodal body. The numerical solution was shown to agree well with existing analytical solutions for several limiting cases (such as flow past a sphere), and was used to investigate the effects of the (a) body shape, (b) free stream conditions, and (c) fluid elasticity on the local velocity and stress fields. The results of this study indicate that while a submerged spheroid gave rise to strong and highly localized stress fields, an immersed sphere created a stress field of moderate strength extending over larger distances. Also, it was found that the different free stream velocity fields, which included uniform flow, simple extensional flow and converging flow, resulted in different stress fields the strongest of which was produced by the extensional flow. Finally, it was found that the elasticity of the fluid had a profound effect on the local stresses. In some cases, the fore-aft symmetry of the stress field was lost, in others circulatory flow regions were produced downstream, and in all cases the magnitude of the stress tensor was increased as a result of increasing the fluid elasticity.","The computed flow kinematics were further used to calculate the expected molecular orientation and flow birefringence of the macromolecules. A derivation was also made of the flow birefringence to verify that the commonly used form of the stress-optical law is not valid for solutions of rigid chains. In addition, the free energy change due to flow was computed and the relationship between the free energy and stress fields and their possible bearing on the flow-induced phase separation of polymers were considered.","Made available in DSpace on 2014-12-15T19:54:15Z (GMT). No. of bitstreams: 1 8502123.pdf: 4070624 bytes, checksum: 854d544cb1b034e98153706ef54058d2 (MD5) Previous issue date: 1984","Embargo set by: Seth Robbins for item 69908 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","U of I Only","173 p.","Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1984."]},{"key":"dc:title","label":"Title","values":["Viscoelastic Fluid Flow Past a Submerged Spheroidal Body (Birefringence, Free Energy)"]}]}],"canonical_facts":{"dc:creator":["Dairanieh, Issam Salah"],"dc:date":["2014-12-15T19:54:15Z","10000-01-01","1984"],"dc:description":["A stable and time-efficient numerical algorithm has been developed to study the problem of homogeneous axisymmetric flow of a third order fluid past a spheriodal body. The numerical solution was shown to agree well with existing analytical solutions for several limiting cases (such as flow past a sphere), and was used to investigate the effects of the (a) body shape, (b) free stream conditions, and (c) fluid elasticity on the local velocity and stress fields. The results of this study indicate that while a submerged spheroid gave rise to strong and highly localized stress fields, an immersed sphere created a stress field of moderate strength extending over larger distances. Also, it was found that the different free stream velocity fields, which included uniform flow, simple extensional flow and converging flow, resulted in different stress fields the strongest of which was produced by the extensional flow. Finally, it was found that the elasticity of the fluid had a profound effect on the local stresses. In some cases, the fore-aft symmetry of the stress field was lost, in others circulatory flow regions were produced downstream, and in all cases the magnitude of the stress tensor was increased as a result of increasing the fluid elasticity.","The computed flow kinematics were further used to calculate the expected molecular orientation and flow birefringence of the macromolecules. A derivation was also made of the flow birefringence to verify that the commonly used form of the stress-optical law is not valid for solutions of rigid chains. In addition, the free energy change due to flow was computed and the relationship between the free energy and stress fields and their possible bearing on the flow-induced phase separation of polymers were considered.","Made available in DSpace on 2014-12-15T19:54:15Z (GMT). No. of bitstreams: 1 8502123.pdf: 4070624 bytes, checksum: 854d544cb1b034e98153706ef54058d2 (MD5) Previous issue date: 1984","Embargo set by: Seth Robbins for item 69908 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","U of I Only","173 p.","Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1984."],"dc:identifier":["http://hdl.handle.net/2142/69742","(UMI)AAI8502123"],"dc:subject":["Engineering, Chemical"],"dc:title":["Viscoelastic Fluid Flow Past a Submerged Spheroidal Body (Birefringence, Free Energy)"],"dc:type":["text"],"thesis:degree_discipline":["Chemical Engineering"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:26:01Z"}