{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/23337"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/23337","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Comparisons of computational methods to represent electron transport in nonequilibrium plasma devices","abstract":"Low pressure optically triggered pseudosparks, or Back-Lit Thyratrons (BLT), are inherently multidimensional transient devices. The method employed to model electron transport in such devices is therefore problematic. A versatile model for these switches with which to compare different modeling approaches has been developed. In the two-dimensional, time dependent model, fluid equations are solved to obtain the electron and ion densities, and Poisson's equation is solved for the electric potential. These equations can be solved using the local field approximation (LFA), employing conservation equations for the bulk electron energy and momentum, or adding multiple beam components to the electron energy distribution. Combinations of these methods can also be employed. The model has been exercised to determine the parameter space, e.g., gas pressure, voltage, electrode gaps, in which each of these methods can be reliably used. Due to the induction time required to achieve quasi-equilibrium conditions, employing the energy equation and beam components typically slows the response of the switch compared to using the LFA.","abstract_html":"Low pressure optically triggered pseudosparks, or Back-Lit Thyratrons (BLT), are inherently multidimensional transient devices. The method employed to model electron transport in such devices is therefore problematic. A versatile model for these switches with which to compare different modeling approaches has been developed. In the two-dimensional, time dependent model, fluid equations are solved to obtain the electron and ion densities, and Poisson's equation is solved for the electric potential. These equations can be solved using the local field approximation (LFA), employing conservation equations for the bulk electron energy and momentum, or adding multiple beam components to the electron energy distribution. Combinations of these methods can also be employed. The model has been exercised to determine the parameter space, e.g., gas pressure, voltage, electrode gaps, in which each of these methods can be reliably used. Due to the induction time required to achieve quasi-equilibrium conditions, employing the energy equation and beam components typically slows the response of the switch compared to using the LFA.","abstract_has_math":false,"creators":["Pak, Hoyoung"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Electrical and Computer Engineering","degree_department":null,"school":null,"contributors":["Kushner, Mark J."],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2011,"date_issued":"2011-05-07T14:10:34Z","date_published":"2011-05-07T14:10:34Z","updated_at":"2026-07-22T22:25:21Z","subjects":["Physics, Fluid and Plasma"],"languages":["eng"],"rights":["Copyright 1991 Pak, Hoyoung"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI9136688","(UMI)AAI9136688"],"render_values":[{"text":"AAI9136688","href":null,"code":true},{"text":"(UMI)AAI9136688","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/23337","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Kushner, Mark J."]},{"key":"dc:creator","label":"Author","values":["Pak, Hoyoung"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2011-05-07T14:10:34Z","10000-01-01","1991"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Electrical and Computer 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":["Physics, Fluid and Plasma"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 1991 Pak, Hoyoung"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI9136688","(UMI)AAI9136688","http://hdl.handle.net/2142/23337"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Low pressure optically triggered pseudosparks, or Back-Lit Thyratrons (BLT), are inherently multidimensional transient devices. The method employed to model electron transport in such devices is therefore problematic. A versatile model for these switches with which to compare different modeling approaches has been developed. In the two-dimensional, time dependent model, fluid equations are solved to obtain the electron and ion densities, and Poisson's equation is solved for the electric potential. These equations can be solved using the local field approximation (LFA), employing conservation equations for the bulk electron energy and momentum, or adding multiple beam components to the electron energy distribution. Combinations of these methods can also be employed. The model has been exercised to determine the parameter space, e.g., gas pressure, voltage, electrode gaps, in which each of these methods can be reliably used. Due to the induction time required to achieve quasi-equilibrium conditions, employing the energy equation and beam components typically slows the response of the switch compared to using the LFA.","A separate model has also been developed to study breakdown in BLTs. In parallel plane geometries, the Paschen curve can be used to predict breakdown voltages as a function of $p\\cdot d$ (gas pressure $\\times$ electrode separation). When electrodes are not planar, i.e., central holes in electrodes, the breakdown deviates from that given by the Paschen curve. The details of the breakdown conditions for hollow electrode geometries have been investigated, and scaling laws derived.","Made available in DSpace on 2011-05-07T14:10:34Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9136688.pdf: 7348165 bytes, checksum: 9e3ea9fd949c8995925a48b530f59e79 (MD5) Previous issue date: 1991","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T15:03:47Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:30:25-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission","ETDs are only available to UIUC Users without author permission","U of I Only"]},{"key":"dc:title","label":"Title","values":["Comparisons of computational methods to represent electron transport in nonequilibrium plasma devices"]}]}],"canonical_facts":{"dc:contributor":["Kushner, Mark J."],"dc:creator":["Pak, Hoyoung"],"dc:date":["2011-05-07T14:10:34Z","10000-01-01","1991"],"dc:description":["Low pressure optically triggered pseudosparks, or Back-Lit Thyratrons (BLT), are inherently multidimensional transient devices. The method employed to model electron transport in such devices is therefore problematic. A versatile model for these switches with which to compare different modeling approaches has been developed. In the two-dimensional, time dependent model, fluid equations are solved to obtain the electron and ion densities, and Poisson's equation is solved for the electric potential. These equations can be solved using the local field approximation (LFA), employing conservation equations for the bulk electron energy and momentum, or adding multiple beam components to the electron energy distribution. Combinations of these methods can also be employed. The model has been exercised to determine the parameter space, e.g., gas pressure, voltage, electrode gaps, in which each of these methods can be reliably used. Due to the induction time required to achieve quasi-equilibrium conditions, employing the energy equation and beam components typically slows the response of the switch compared to using the LFA.","A separate model has also been developed to study breakdown in BLTs. In parallel plane geometries, the Paschen curve can be used to predict breakdown voltages as a function of $p\\cdot d$ (gas pressure $\\times$ electrode separation). When electrodes are not planar, i.e., central holes in electrodes, the breakdown deviates from that given by the Paschen curve. The details of the breakdown conditions for hollow electrode geometries have been investigated, and scaling laws derived.","Made available in DSpace on 2011-05-07T14:10:34Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9136688.pdf: 7348165 bytes, checksum: 9e3ea9fd949c8995925a48b530f59e79 (MD5) Previous issue date: 1991","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T15:03:47Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:30:25-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission","ETDs are only available to UIUC Users without author permission","U of I Only"],"dc:identifier":["AAI9136688","(UMI)AAI9136688","http://hdl.handle.net/2142/23337"],"dc:language":["eng"],"dc:rights":["Copyright 1991 Pak, Hoyoung"],"dc:subject":["Physics, Fluid and Plasma"],"dc:title":["Comparisons of computational methods to represent electron transport in nonequilibrium plasma devices"],"dc:type":["text"],"thesis:degree_discipline":["Electrical and Computer Engineering"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:25:21Z"}