{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/87752"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/87752","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Random Packs and Their Use in Modeling High Speed Porous Flow","abstract":"Random packs of spheres have been used to model heterogeneous and porous material morphologies during simulations of physical processes such as burning of coal char, convective burning in porous explosives, and regression of solid rocket propellant. Sphere packs have also been used to predict thermo-mechanical properties, permeability, packing density, and dissolution characteristics of various materials. In this work, we have used the Lubachevsky-Stillinger (LS) packing algorithm to create polydisperse packs of spheres for modeling heterogeneity in solid rocket grains. We have greatly improved upon the computational efficiency of the original algorithm by using hierarchical cells in 3D. The speed-up enables the generation of polydisperse packs of millions of spheres on serial workstations and laptops. We have statistically characterized these large packs and validated the results against published experiments. Furthermore, we have extended the LS sphere packing framework by incorporating a level set scheme to pack non-spherical shapes that are more relevant in many complex materials such as HMX and pressed gun propellants. We have obtained results for dense random packs of various convex shapes such as gel capsules, cylinders, and polyhedra. As an example application, we present preliminary results of numerical experiments of compressible, large Mach number gas permeation into packs of polydisperse spherical and non-spherical particles.","abstract_html":"Random packs of spheres have been used to model heterogeneous and porous material morphologies during simulations of physical processes such as burning of coal char, convective burning in porous explosives, and regression of solid rocket propellant. Sphere packs have also been used to predict thermo-mechanical properties, permeability, packing density, and dissolution characteristics of various materials. In this work, we have used the Lubachevsky-Stillinger (LS) packing algorithm to create polydisperse packs of spheres for modeling heterogeneity in solid rocket grains. We have greatly improved upon the computational efficiency of the original algorithm by using hierarchical cells in 3D. The speed-up enables the generation of polydisperse packs of millions of spheres on serial workstations and laptops. We have statistically characterized these large packs and validated the results against published experiments. Furthermore, we have extended the LS sphere packing framework by incorporating a level set scheme to pack non-spherical shapes that are more relevant in many complex materials such as HMX and pressed gun propellants. We have obtained results for dense random packs of various convex shapes such as gel capsules, cylinders, and polyhedra. As an example application, we present preliminary results of numerical experiments of compressible, large Mach number gas permeation into packs of polydisperse spherical and non-spherical particles.","abstract_has_math":false,"creators":["Stafford, David Shane"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Theoretical and Applied Mechanics","degree_department":null,"school":null,"contributors":["Thomas Jackson"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2015,"date_issued":"2015-09-28T16:23:48Z","date_published":"2015-09-28T16:23:48Z","updated_at":"2026-07-22T22:26:30Z","subjects":["Applied Mechanics"],"languages":["eng"],"rights":[],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["(MiAaPQ)AAI3347515"],"render_values":[{"text":"(MiAaPQ)AAI3347515","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/87752","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Thomas Jackson"]},{"key":"dc:creator","label":"Author","values":["Stafford, David Shane"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2015-09-28T16:23:48Z","10000-01-01","2008"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Theoretical and Applied Mechanics"]},{"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":["Applied Mechanics"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/2142/87752","(MiAaPQ)AAI3347515"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Random packs of spheres have been used to model heterogeneous and porous material morphologies during simulations of physical processes such as burning of coal char, convective burning in porous explosives, and regression of solid rocket propellant. Sphere packs have also been used to predict thermo-mechanical properties, permeability, packing density, and dissolution characteristics of various materials. In this work, we have used the Lubachevsky-Stillinger (LS) packing algorithm to create polydisperse packs of spheres for modeling heterogeneity in solid rocket grains. We have greatly improved upon the computational efficiency of the original algorithm by using hierarchical cells in 3D. The speed-up enables the generation of polydisperse packs of millions of spheres on serial workstations and laptops. We have statistically characterized these large packs and validated the results against published experiments. Furthermore, we have extended the LS sphere packing framework by incorporating a level set scheme to pack non-spherical shapes that are more relevant in many complex materials such as HMX and pressed gun propellants. We have obtained results for dense random packs of various convex shapes such as gel capsules, cylinders, and polyhedra. As an example application, we present preliminary results of numerical experiments of compressible, large Mach number gas permeation into packs of polydisperse spherical and non-spherical particles.","Made available in DSpace on 2015-09-28T16:23:48Z (GMT). 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Sphere packs have also been used to predict thermo-mechanical properties, permeability, packing density, and dissolution characteristics of various materials. In this work, we have used the Lubachevsky-Stillinger (LS) packing algorithm to create polydisperse packs of spheres for modeling heterogeneity in solid rocket grains. We have greatly improved upon the computational efficiency of the original algorithm by using hierarchical cells in 3D. The speed-up enables the generation of polydisperse packs of millions of spheres on serial workstations and laptops. We have statistically characterized these large packs and validated the results against published experiments. Furthermore, we have extended the LS sphere packing framework by incorporating a level set scheme to pack non-spherical shapes that are more relevant in many complex materials such as HMX and pressed gun propellants. We have obtained results for dense random packs of various convex shapes such as gel capsules, cylinders, and polyhedra. As an example application, we present preliminary results of numerical experiments of compressible, large Mach number gas permeation into packs of polydisperse spherical and non-spherical particles.","Made available in DSpace on 2015-09-28T16:23:48Z (GMT). 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