{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/17396"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/17396","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Post-shock thermochemistry in hypervelocity CO2 and air flow","abstract":"This work represents ongoing efforts to study high-enthalpy carbon dioxide flows in anticipation of the upcoming Mars Science Laboratory (MSL) and future missions to the red planet. The work is motivated by observed anomalies between experimental and numerical studies in hypervelocity impulse facilities for high enthalpy carbon dioxide flows. In this work, experiments are conducted in the Hypervelocity Expansion Tube (HET) which, by virtue of its flow acceleration process, exhibits minimal freestream dissociation in comparison to reflected shock tunnels. This simplifies the comparison with computational result as freestream dissociation and considerable thermochemical excitation can be neglected. Shock shapes of the MSL aeroshell and spherical geometries are compared with numerical simulations incorporating detailed CO2 thermochemical modeling. The shock stand-off distance has been identified in the past as sensitive to the thermochemical state and as such, is used here as an experimental measurable for comparison with CFD and two different theoretical models. It is seen that models based upon binary scaling assumptions are not applicable for the low-density, small-scale conditions of the current work. Mars Science Laboratory shock shapes at zero angle of attack are also in good agreement with available data from the LENS X expansion tunnel facility, confi rming results are facility-independent for the same type of flow acceleration, and indicating that the flow velocity is a suitable first-order matching parameter for comparative testing. In an e ffort to address surface chemistry issues arising from high-enthalpy carbon dioxide ground-test based experiments, spherical stagnation point and aeroshell heat transfer distributions are also compared with simulation. Very good agreement between experiment and CFD is seen for all shock shapes and heat transfer distributions fall within the non-catalytic and super-catalytic solutions. We also examine spatial temperature profiles in the non-equilibrium relaxation region behind a stationary shock wave in a hypervelocity air Mach 7.42 freestream. The normal shock wave is established through a Mach reflection from an opposing wedge arrangement. Schlieren images confirm that the shock con guration is steady and the location is repeatable. Emission spectroscopy is used to identify dissociated species and to make vibrational temperature measurements using both the nitric oxide and the hydroxyl radical A-X band sequences. Temperature measurements are presented at selected locations behind the normal shock. LIFBASE is used as the simulation spectrum software for OH temperature-fitting, however the need to access higher vibrational and rotational levels for NO leads to the use of an in-house developed algorithm. For NO, results demonstrate the contribution of higher vibrational and rotational levels to the spectra at the conditions of this study. Very good agreement is achieved between the experimentally measured NO vibrational temperatures and calculations performed using an existing state-resolved, three-dimensional forced harmonic oscillator thermochemical model. The measured NO A-X vibrational temperatures are significantly higher than the OH A-X temperatures.","abstract_html":"This work represents ongoing efforts to study high-enthalpy carbon dioxide flows in anticipation of the upcoming Mars Science Laboratory (MSL) and future missions to the red planet. The work is motivated by observed anomalies between experimental and numerical studies in hypervelocity impulse facilities for high enthalpy carbon dioxide flows. In this work, experiments are conducted in the Hypervelocity Expansion Tube (HET) which, by virtue of its flow acceleration process, exhibits minimal freestream dissociation in comparison to reflected shock tunnels. This simplifies the comparison with computational result as freestream dissociation and considerable thermochemical excitation can be neglected. Shock shapes of the MSL aeroshell and spherical geometries are compared with numerical simulations incorporating detailed CO2 thermochemical modeling. The shock stand-off distance has been identified in the past as sensitive to the thermochemical state and as such, is used here as an experimental measurable for comparison with CFD and two different theoretical models. It is seen that models based upon binary scaling assumptions are not applicable for the low-density, small-scale conditions of the current work. Mars Science Laboratory shock shapes at zero angle of attack are also in good agreement with available data from the LENS X expansion tunnel facility, confi rming results are facility-independent for the same type of flow acceleration, and indicating that the flow velocity is a suitable first-order matching parameter for comparative testing. In an e ffort to address surface chemistry issues arising from high-enthalpy carbon dioxide ground-test based experiments, spherical stagnation point and aeroshell heat transfer distributions are also compared with simulation. Very good agreement between experiment and CFD is seen for all shock shapes and heat transfer distributions fall within the non-catalytic and super-catalytic solutions. We also examine spatial temperature profiles in the non-equilibrium relaxation region behind a stationary shock wave in a hypervelocity air Mach 7.42 freestream. The normal shock wave is established through a Mach reflection from an opposing wedge arrangement. Schlieren images confirm that the shock con guration is steady and the location is repeatable. Emission spectroscopy is used to identify dissociated species and to make vibrational temperature measurements using both the nitric oxide and the hydroxyl radical A-X band sequences. Temperature measurements are presented at selected locations behind the normal shock. LIFBASE is used as the simulation spectrum software for OH temperature-fitting, however the need to access higher vibrational and rotational levels for NO leads to the use of an in-house developed algorithm. For NO, results demonstrate the contribution of higher vibrational and rotational levels to the spectra at the conditions of this study. Very good agreement is achieved between the experimentally measured NO vibrational temperatures and calculations performed using an existing state-resolved, three-dimensional forced harmonic oscillator thermochemical model. The measured NO A-X vibrational temperatures are significantly higher than the OH A-X temperatures.","abstract_has_math":false,"creators":["Sharma, Manu"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Aerospace Engineering","degree_department":null,"school":null,"contributors":["Elliott, Gregory S.","Austin, Joanna M.","Glumac, Nick G.","Christensen, Kenneth T."],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2010,"date_issued":"2010-11-08T15:48:30Z","date_published":"2010-11-08T15:48:30Z","updated_at":"2026-07-22T22:25:09Z","subjects":["hypersonic","hypervelocity","high-enthalpy","Mars Science Laboratory","spectroscopy","heat transfer"],"languages":["en"],"rights":["Copyright 2010 Manu Sharma"],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/2142/17396","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Elliott, Gregory S.","Austin, Joanna M.","Glumac, Nick G.","Christensen, Kenneth T."]},{"key":"dc:creator","label":"Author","values":["Sharma, Manu"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2010-11-08T15:48:30Z","2010-08"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Aerospace 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":["hypersonic","hypervelocity","high-enthalpy","Mars Science Laboratory","spectroscopy","heat transfer"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["en"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 2010 Manu Sharma"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/2142/17396"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["This work represents ongoing efforts to study high-enthalpy carbon dioxide flows in anticipation of the upcoming Mars Science Laboratory (MSL) and future missions to the red planet. The work is motivated by observed anomalies between experimental and numerical studies in hypervelocity impulse facilities for high enthalpy carbon dioxide flows. In this work, experiments are conducted in the Hypervelocity Expansion Tube (HET) which, by virtue of its flow acceleration process, exhibits minimal freestream dissociation in comparison to reflected shock tunnels. This simplifies the comparison with computational result as freestream dissociation and considerable thermochemical excitation can be neglected. Shock shapes of the MSL aeroshell and spherical geometries are compared with numerical simulations incorporating detailed CO2 thermochemical modeling. The shock stand-off distance has been identified in the past as sensitive to the thermochemical state and as such, is used here as an experimental measurable for comparison with CFD and two different theoretical models. It is seen that models based upon binary scaling assumptions are not applicable for the low-density, small-scale conditions of the current work. Mars Science Laboratory shock shapes at zero angle of attack are also in good agreement with available data from the LENS X expansion tunnel facility, confi rming results are facility-independent for the same type of flow acceleration, and indicating that the flow velocity is a suitable first-order matching parameter for comparative testing. In an e ffort to address surface chemistry issues arising from high-enthalpy carbon dioxide ground-test based experiments, spherical stagnation point and aeroshell heat transfer distributions are also compared with simulation. Very good agreement between experiment and CFD is seen for all shock shapes and heat transfer distributions fall within the non-catalytic and super-catalytic solutions. We also examine spatial temperature profiles in the non-equilibrium relaxation region behind a stationary shock wave in a hypervelocity air Mach 7.42 freestream. The normal shock wave is established through a Mach reflection from an opposing wedge arrangement. Schlieren images confirm that the shock con guration is steady and the location is repeatable. Emission spectroscopy is used to identify dissociated species and to make vibrational temperature measurements using both the nitric oxide and the hydroxyl radical A-X band sequences. Temperature measurements are presented at selected locations behind the normal shock. LIFBASE is used as the simulation spectrum software for OH temperature-fitting, however the need to access higher vibrational and rotational levels for NO leads to the use of an in-house developed algorithm. For NO, results demonstrate the contribution of higher vibrational and rotational levels to the spectra at the conditions of this study. Very good agreement is achieved between the experimentally measured NO vibrational temperatures and calculations performed using an existing state-resolved, three-dimensional forced harmonic oscillator thermochemical model. The measured NO A-X vibrational temperatures are significantly higher than the OH A-X temperatures.","Item withdrawn by Mark Zulauf (zulauf@illinois.edu) on 2010-07-06T15:00:27Z Item was in collections: University of Illinois Theses & Dissertations (ID: 1) No. of bitstreams: 17 Wedge_Designs.tex: 670 bytes, checksum: d8cb2b1eb00513f15378ceda90d043bc (MD5) knife_blade.tex: 1451 bytes, checksum: c39ad8b0a65de89ea050e79aebdc15b4 (MD5) MSL_Drawings.tex: 1225 bytes, checksum: 4e0fdd5c95299e8c2e2201fa4a24e1fa (MD5) Sting_Drawings.tex: 1234 bytes, checksum: c7f4608ebc1a766a81c9c3f5ac0745c7 (MD5) shockpolar.tex: 7272 bytes, checksum: 624a76743fe947a2ef2e7f48b60c410b (MD5) appendix_spectroscopy.tex: 8406 bytes, checksum: a7bd92b906fd1b44ba8c6b2d9a78bf6a (MD5) mirels_effect.tex: 6003 bytes, checksum: 9201514f15996a66cb2af9751d20797f (MD5) appendix_spectroscopy.tex: 8406 bytes, checksum: a7bd92b906fd1b44ba8c6b2d9a78bf6a (MD5) appendix_delta.tex: 3659 bytes, checksum: 958614b1e7aec6d9ee194fdf5ebdb485 (MD5) conclusions.tex: 10220 bytes, checksum: 1b9231ba076910ad7dcd5f6505c782fd (MD5) carbon_dioxide_reorg.tex: 70790 bytes, checksum: 6292b1e49306120b83f2e90547a6dd19 (MD5) spectroscopy.tex: 55185 bytes, checksum: b96db24aa24113978996bdd928988352 (MD5) Experimental_Setup.tex: 19450 bytes, checksum: 977359d24ca23fbe5c8014a9d30605a0 (MD5) background.tex: 13392 bytes, checksum: 337c21ef7ff862207971936644b1e5d8 (MD5) dissertation.tex: 5054 bytes, checksum: 8e62bd09ded08880ccd743dbd3abece2 (MD5) abstract.tex: 3307 bytes, checksum: d7429fcba5b373f9050721170bee6fac (MD5) Sharma_Manu.pdf: 16013052 bytes, checksum: b4eb8aef73bbaab25ced51f6fb8bf76f (MD5)","Made available in DSpace on 2010-11-08T15:48:30Z (GMT). No. of bitstreams: 19 Sharma_Manu.pdf: 16013052 bytes, checksum: b4eb8aef73bbaab25ced51f6fb8bf76f (MD5) Wedge_Designs.tex: 670 bytes, checksum: d8cb2b1eb00513f15378ceda90d043bc (MD5) knife_blade.tex: 1451 bytes, checksum: c39ad8b0a65de89ea050e79aebdc15b4 (MD5) MSL_Drawings.tex: 1225 bytes, checksum: 4e0fdd5c95299e8c2e2201fa4a24e1fa (MD5) Sting_Drawings.tex: 1234 bytes, checksum: c7f4608ebc1a766a81c9c3f5ac0745c7 (MD5) shockpolar.tex: 7272 bytes, checksum: 624a76743fe947a2ef2e7f48b60c410b (MD5) appendix_spectroscopy.tex: 8406 bytes, checksum: a7bd92b906fd1b44ba8c6b2d9a78bf6a (MD5) mirels_effect.tex: 6003 bytes, checksum: 9201514f15996a66cb2af9751d20797f (MD5) 1_appendix_spectroscopy.tex: 8406 bytes, checksum: a7bd92b906fd1b44ba8c6b2d9a78bf6a (MD5) appendix_delta.tex: 3659 bytes, checksum: 958614b1e7aec6d9ee194fdf5ebdb485 (MD5) conclusions.tex: 10220 bytes, checksum: 1b9231ba076910ad7dcd5f6505c782fd (MD5) carbon_dioxide_reorg.tex: 70790 bytes, checksum: 6292b1e49306120b83f2e90547a6dd19 (MD5) spectroscopy.tex: 55185 bytes, checksum: b96db24aa24113978996bdd928988352 (MD5) Experimental_Setup.tex: 19450 bytes, checksum: 977359d24ca23fbe5c8014a9d30605a0 (MD5) background.tex: 13392 bytes, checksum: 337c21ef7ff862207971936644b1e5d8 (MD5) dissertation.tex: 5054 bytes, checksum: 8e62bd09ded08880ccd743dbd3abece2 (MD5) abstract.tex: 3307 bytes, checksum: d7429fcba5b373f9050721170bee6fac (MD5) 1_Sharma_Manu.pdf: 16078320 bytes, checksum: 2e6f89c87ad57715f36aed49f7e3a5aa (MD5) license.txt: 4061 bytes, checksum: aa65df70ae3a50c8f1d3699bf44fb316 (MD5)"]},{"key":"dc:title","label":"Title","values":["Post-shock thermochemistry in hypervelocity CO2 and air flow"]}]}],"canonical_facts":{"dc:contributor":["Elliott, Gregory S.","Austin, Joanna M.","Glumac, Nick G.","Christensen, Kenneth T."],"dc:creator":["Sharma, Manu"],"dc:date":["2010-11-08T15:48:30Z","2010-08"],"dc:description":["This work represents ongoing efforts to study high-enthalpy carbon dioxide flows in anticipation of the upcoming Mars Science Laboratory (MSL) and future missions to the red planet. The work is motivated by observed anomalies between experimental and numerical studies in hypervelocity impulse facilities for high enthalpy carbon dioxide flows. In this work, experiments are conducted in the Hypervelocity Expansion Tube (HET) which, by virtue of its flow acceleration process, exhibits minimal freestream dissociation in comparison to reflected shock tunnels. This simplifies the comparison with computational result as freestream dissociation and considerable thermochemical excitation can be neglected. Shock shapes of the MSL aeroshell and spherical geometries are compared with numerical simulations incorporating detailed CO2 thermochemical modeling. The shock stand-off distance has been identified in the past as sensitive to the thermochemical state and as such, is used here as an experimental measurable for comparison with CFD and two different theoretical models. It is seen that models based upon binary scaling assumptions are not applicable for the low-density, small-scale conditions of the current work. Mars Science Laboratory shock shapes at zero angle of attack are also in good agreement with available data from the LENS X expansion tunnel facility, confi rming results are facility-independent for the same type of flow acceleration, and indicating that the flow velocity is a suitable first-order matching parameter for comparative testing. In an e ffort to address surface chemistry issues arising from high-enthalpy carbon dioxide ground-test based experiments, spherical stagnation point and aeroshell heat transfer distributions are also compared with simulation. Very good agreement between experiment and CFD is seen for all shock shapes and heat transfer distributions fall within the non-catalytic and super-catalytic solutions. We also examine spatial temperature profiles in the non-equilibrium relaxation region behind a stationary shock wave in a hypervelocity air Mach 7.42 freestream. The normal shock wave is established through a Mach reflection from an opposing wedge arrangement. Schlieren images confirm that the shock con guration is steady and the location is repeatable. Emission spectroscopy is used to identify dissociated species and to make vibrational temperature measurements using both the nitric oxide and the hydroxyl radical A-X band sequences. Temperature measurements are presented at selected locations behind the normal shock. LIFBASE is used as the simulation spectrum software for OH temperature-fitting, however the need to access higher vibrational and rotational levels for NO leads to the use of an in-house developed algorithm. For NO, results demonstrate the contribution of higher vibrational and rotational levels to the spectra at the conditions of this study. Very good agreement is achieved between the experimentally measured NO vibrational temperatures and calculations performed using an existing state-resolved, three-dimensional forced harmonic oscillator thermochemical model. The measured NO A-X vibrational temperatures are significantly higher than the OH A-X temperatures.","Item withdrawn by Mark Zulauf (zulauf@illinois.edu) on 2010-07-06T15:00:27Z Item was in collections: University of Illinois Theses & Dissertations (ID: 1) No. of bitstreams: 17 Wedge_Designs.tex: 670 bytes, checksum: d8cb2b1eb00513f15378ceda90d043bc (MD5) knife_blade.tex: 1451 bytes, checksum: c39ad8b0a65de89ea050e79aebdc15b4 (MD5) MSL_Drawings.tex: 1225 bytes, checksum: 4e0fdd5c95299e8c2e2201fa4a24e1fa (MD5) Sting_Drawings.tex: 1234 bytes, checksum: c7f4608ebc1a766a81c9c3f5ac0745c7 (MD5) shockpolar.tex: 7272 bytes, checksum: 624a76743fe947a2ef2e7f48b60c410b (MD5) appendix_spectroscopy.tex: 8406 bytes, checksum: a7bd92b906fd1b44ba8c6b2d9a78bf6a (MD5) mirels_effect.tex: 6003 bytes, checksum: 9201514f15996a66cb2af9751d20797f (MD5) appendix_spectroscopy.tex: 8406 bytes, checksum: a7bd92b906fd1b44ba8c6b2d9a78bf6a (MD5) appendix_delta.tex: 3659 bytes, checksum: 958614b1e7aec6d9ee194fdf5ebdb485 (MD5) conclusions.tex: 10220 bytes, checksum: 1b9231ba076910ad7dcd5f6505c782fd (MD5) carbon_dioxide_reorg.tex: 70790 bytes, checksum: 6292b1e49306120b83f2e90547a6dd19 (MD5) spectroscopy.tex: 55185 bytes, checksum: b96db24aa24113978996bdd928988352 (MD5) Experimental_Setup.tex: 19450 bytes, checksum: 977359d24ca23fbe5c8014a9d30605a0 (MD5) background.tex: 13392 bytes, checksum: 337c21ef7ff862207971936644b1e5d8 (MD5) dissertation.tex: 5054 bytes, checksum: 8e62bd09ded08880ccd743dbd3abece2 (MD5) abstract.tex: 3307 bytes, checksum: d7429fcba5b373f9050721170bee6fac (MD5) Sharma_Manu.pdf: 16013052 bytes, checksum: b4eb8aef73bbaab25ced51f6fb8bf76f (MD5)","Made available in DSpace on 2010-11-08T15:48:30Z (GMT). No. of bitstreams: 19 Sharma_Manu.pdf: 16013052 bytes, checksum: b4eb8aef73bbaab25ced51f6fb8bf76f (MD5) Wedge_Designs.tex: 670 bytes, checksum: d8cb2b1eb00513f15378ceda90d043bc (MD5) knife_blade.tex: 1451 bytes, checksum: c39ad8b0a65de89ea050e79aebdc15b4 (MD5) MSL_Drawings.tex: 1225 bytes, checksum: 4e0fdd5c95299e8c2e2201fa4a24e1fa (MD5) Sting_Drawings.tex: 1234 bytes, checksum: c7f4608ebc1a766a81c9c3f5ac0745c7 (MD5) shockpolar.tex: 7272 bytes, checksum: 624a76743fe947a2ef2e7f48b60c410b (MD5) appendix_spectroscopy.tex: 8406 bytes, checksum: a7bd92b906fd1b44ba8c6b2d9a78bf6a (MD5) mirels_effect.tex: 6003 bytes, checksum: 9201514f15996a66cb2af9751d20797f (MD5) 1_appendix_spectroscopy.tex: 8406 bytes, checksum: a7bd92b906fd1b44ba8c6b2d9a78bf6a (MD5) appendix_delta.tex: 3659 bytes, checksum: 958614b1e7aec6d9ee194fdf5ebdb485 (MD5) conclusions.tex: 10220 bytes, checksum: 1b9231ba076910ad7dcd5f6505c782fd (MD5) carbon_dioxide_reorg.tex: 70790 bytes, checksum: 6292b1e49306120b83f2e90547a6dd19 (MD5) spectroscopy.tex: 55185 bytes, checksum: b96db24aa24113978996bdd928988352 (MD5) Experimental_Setup.tex: 19450 bytes, checksum: 977359d24ca23fbe5c8014a9d30605a0 (MD5) background.tex: 13392 bytes, checksum: 337c21ef7ff862207971936644b1e5d8 (MD5) dissertation.tex: 5054 bytes, checksum: 8e62bd09ded08880ccd743dbd3abece2 (MD5) abstract.tex: 3307 bytes, checksum: d7429fcba5b373f9050721170bee6fac (MD5) 1_Sharma_Manu.pdf: 16078320 bytes, checksum: 2e6f89c87ad57715f36aed49f7e3a5aa (MD5) license.txt: 4061 bytes, checksum: aa65df70ae3a50c8f1d3699bf44fb316 (MD5)"],"dc:identifier":["http://hdl.handle.net/2142/17396"],"dc:language":["en"],"dc:rights":["Copyright 2010 Manu Sharma"],"dc:subject":["hypersonic","hypervelocity","high-enthalpy","Mars Science Laboratory","spectroscopy","heat transfer"],"dc:title":["Post-shock thermochemistry in hypervelocity CO2 and air flow"],"thesis:degree_discipline":["Aerospace Engineering"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:25:09Z"}