{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/70628"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/70628","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Numerical Solutions of Nonlinear Free-Surface Wave Problems (Numerical Analysis, Filtering, Artificial Viscosity)","abstract":"A numerical method was developed for solving potential flows for nonlinear free-surface wave problems with a fixed, small computational domain. The free-surface wave problem is solved as an initial value problem. The method of solving the free-surface wave problem couples the solution of the free-surface partial differential equations with the solution of the Laplace equation. The efficiency of the method is increased by solving the problem on a fixed, small computational domain, using an open boundary condition.","abstract_html":"A numerical method was developed for solving potential flows for nonlinear free-surface wave problems with a fixed, small computational domain. The free-surface wave problem is solved as an initial value problem. The method of solving the free-surface wave problem couples the solution of the free-surface partial differential equations with the solution of the Laplace equation. The efficiency of the method is increased by solving the problem on a fixed, small computational domain, using an open boundary condition.","abstract_has_math":false,"creators":["Hall, Douglas Ralph"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Aeronautical and Astronautical Engineering","degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2014,"date_issued":"2014-12-15T23:55:54Z","date_published":"2014-12-15T23:55:54Z","updated_at":"2026-07-22T22:26:03Z","subjects":["Engineering, Aerospace"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["(UMI)AAI8502160"],"render_values":[{"text":"(UMI)AAI8502160","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/70628","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Hall, Douglas Ralph"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2014-12-15T23:55:54Z","10000-01-01","1984"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Aeronautical and Astronautical 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, Aerospace"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/2142/70628","(UMI)AAI8502160"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["A numerical method was developed for solving potential flows for nonlinear free-surface wave problems with a fixed, small computational domain. The free-surface wave problem is solved as an initial value problem. The method of solving the free-surface wave problem couples the solution of the free-surface partial differential equations with the solution of the Laplace equation. The efficiency of the method is increased by solving the problem on a fixed, small computational domain, using an open boundary condition.","The implementation of the open boundary condition was studied by conducting a set of numerical experiments and by implementing the open boundary condition in the pressure-distribution problem at the outflow boundary, placed close to the pressure-distribution. The numerical experiments were conducted to systematically study the error in the calculation and to select an accurate numerical scheme.","Two methods were used to calculate accurate solutions of the free-surface equations and to control high frequency waves. The first method was to filter to control the high frequency waves. The second method was to use a damping scheme to solve the free-surface equations. The damping scheme was developed in three steps: modify the existing undamped schemes, incorporate artificial viscosity into the modified schemes by using upwind differencing, and, lastly, analyze the damping schemes to determine the effect of artificial viscosity on the solution of the free-surface equations. The damping scheme was more effective in calculating an accurate solution to the free-surface equations.","Unsteady and long time solutions were obtained for the pressure-distribution problem. At the higher Froude numbers, the nonlinearity of the wave-height solution was significant. An unsteady solution to the three-dimensional ship-wave problem was obtained.","Made available in DSpace on 2014-12-15T23:55:54Z (GMT). No. of bitstreams: 1 8502160.pdf: 3769385 bytes, checksum: 0ad5ad4a688a2130aa817772ac65ade3 (MD5) Previous issue date: 1984","Embargo set by: Seth Robbins for item 70794 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","133 p.","Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1984."]},{"key":"dc:title","label":"Title","values":["Numerical Solutions of Nonlinear Free-Surface Wave Problems (Numerical Analysis, Filtering, Artificial Viscosity)"]}]}],"canonical_facts":{"dc:creator":["Hall, Douglas Ralph"],"dc:date":["2014-12-15T23:55:54Z","10000-01-01","1984"],"dc:description":["A numerical method was developed for solving potential flows for nonlinear free-surface wave problems with a fixed, small computational domain. The free-surface wave problem is solved as an initial value problem. The method of solving the free-surface wave problem couples the solution of the free-surface partial differential equations with the solution of the Laplace equation. The efficiency of the method is increased by solving the problem on a fixed, small computational domain, using an open boundary condition.","The implementation of the open boundary condition was studied by conducting a set of numerical experiments and by implementing the open boundary condition in the pressure-distribution problem at the outflow boundary, placed close to the pressure-distribution. The numerical experiments were conducted to systematically study the error in the calculation and to select an accurate numerical scheme.","Two methods were used to calculate accurate solutions of the free-surface equations and to control high frequency waves. The first method was to filter to control the high frequency waves. The second method was to use a damping scheme to solve the free-surface equations. The damping scheme was developed in three steps: modify the existing undamped schemes, incorporate artificial viscosity into the modified schemes by using upwind differencing, and, lastly, analyze the damping schemes to determine the effect of artificial viscosity on the solution of the free-surface equations. The damping scheme was more effective in calculating an accurate solution to the free-surface equations.","Unsteady and long time solutions were obtained for the pressure-distribution problem. At the higher Froude numbers, the nonlinearity of the wave-height solution was significant. An unsteady solution to the three-dimensional ship-wave problem was obtained.","Made available in DSpace on 2014-12-15T23:55:54Z (GMT). No. of bitstreams: 1 8502160.pdf: 3769385 bytes, checksum: 0ad5ad4a688a2130aa817772ac65ade3 (MD5) Previous issue date: 1984","Embargo set by: Seth Robbins for item 70794 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","133 p.","Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1984."],"dc:identifier":["http://hdl.handle.net/2142/70628","(UMI)AAI8502160"],"dc:subject":["Engineering, Aerospace"],"dc:title":["Numerical Solutions of Nonlinear Free-Surface Wave Problems (Numerical Analysis, Filtering, Artificial Viscosity)"],"dc:type":["text"],"thesis:degree_discipline":["Aeronautical and Astronautical Engineering"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:26:03Z"}