{"id":{"repo_id":"mit","oai_identifier":"oai:dspace.mit.edu:1721.1/53527"},"canonical_url":"https://search.dev.ndltd.org/etd/mit/oai:dspace.mit.edu:1721.1/53527","repository":{"repo_id":"mit","name":"MIT","base_url":"https://dspace.mit.edu/oai/request"},"display":{"title":"Dynamic response of the supercritical C0₂ Brayton recompression cycle to various system transients","abstract":"The supercritical carbon dioxide (SC0₂) power conversion system has been suggested for use with many of the Generation IV nuclear reactors. The SC0₂ cycle is highly attractive because of its low operating temperatures and high efficiency associated with working near the critical point of CO2. Unfortunately, the appealing features of using C0₂ near its critical point create complications in control. The Transient SC0₂ Cycles Code (TSCYCO) has been developed as a transient simulation control design and cycle scoping code for the recompression SC0₂ Brayton cycle. It is based off of the SC0₂ Power Systems (SCPS) code, and incorporates many improvements and modifications. Written in FORTRAN 90, TSCYCO uses a lumped parameter model and a momentum integral model approach. The code uses a semi-implicit solution process and implements Gaussian elimination to solve the system of equations. Transient behavior of the printed circuit heat exchangers is determined via the previously developed code HXMOD. Turbomachinery performance is modeled using the Real Gas Radial Compressor (RGRC) code with a scaling scheme for off-design conditions. Currently, TSCYCO has the capability of modeling several transients, including: loss of external load (LOEL), power load change, and cycle low-temperature change. Simulations show that TSCYCO can be run at quasi-steady state for an indefinite period of time. In the case of a 10% LOEL, the axial turbine experiences choke as a result of shaft overspeed. Turbine choke can be avoided if one bypasses more flow during LOEL.","abstract_html":"The supercritical carbon dioxide (SC0₂) power conversion system has been suggested for use with many of the Generation IV nuclear reactors. The SC0₂ cycle is highly attractive because of its low operating temperatures and high efficiency associated with working near the critical point of CO2. Unfortunately, the appealing features of using C0₂ near its critical point create complications in control. The Transient SC0₂ Cycles Code (TSCYCO) has been developed as a transient simulation control design and cycle scoping code for the recompression SC0₂ Brayton cycle. It is based off of the SC0₂ Power Systems (SCPS) code, and incorporates many improvements and modifications. Written in FORTRAN 90, TSCYCO uses a lumped parameter model and a momentum integral model approach. The code uses a semi-implicit solution process and implements Gaussian elimination to solve the system of equations. Transient behavior of the printed circuit heat exchangers is determined via the previously developed code HXMOD. Turbomachinery performance is modeled using the Real Gas Radial Compressor (RGRC) code with a scaling scheme for off-design conditions. Currently, TSCYCO has the capability of modeling several transients, including: loss of external load (LOEL), power load change, and cycle low-temperature change. Simulations show that TSCYCO can be run at quasi-steady state for an indefinite period of time. In the case of a 10% LOEL, the axial turbine experiences choke as a result of shaft overspeed. Turbine choke can be avoided if one bypasses more flow during LOEL.","abstract_has_math":false,"creators":["Trinh, Tri Q. (Tri Quang)"],"institution":"Massachusetts Institute of Technology","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":"Massachusetts Institute of Technology. Dept. of Nuclear Science and Engineering.","school":null,"contributors":[],"advisors":["Pavel Hejzlar and Michael Driscoll."],"committee_chairs":[],"committee_members":[],"year":2009,"date_issued":"2009","date_published":"2009","updated_at":"2026-07-22T22:21:36Z","subjects":["Nuclear Science and Engineering."],"languages":["eng"],"rights":["M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission."],"rights_urls":["http://dspace.mit.edu/handle/1721.1/7582"],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/1721.1/53527","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Pavel Hejzlar and Michael Driscoll."]},{"key":"dc:contributor.department","label":"Department","values":["Massachusetts Institute of Technology. Dept. of Nuclear Science and Engineering."]},{"key":"dc:contributor.other","label":"Dc Contributor Other","values":["Massachusetts Institute of Technology. Dept. of Nuclear Science and Engineering."]},{"key":"dc:creator","label":"Author","values":["Trinh, Tri Q. (Tri Quang)"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2010-04-07T13:05:32Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2010-04-07T13:05:32Z"]},{"key":"dc:date.issued","label":"Date","values":["2009"]},{"key":"dc:publisher","label":"Institution","values":["Massachusetts Institute of Technology"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Nuclear Science and Engineering."]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission."]},{"key":"dc:rights.uri","label":"Rights URI","values":["http://dspace.mit.edu/handle/1721.1/7582"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/1721.1/53527"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Nuclear Science and Engineering, 2009.","Page 208 blank. Cataloged from PDF version of thesis.","Includes bibliographical references (p. 159-160)."]},{"key":"dc:description.abstract","label":"Abstract","values":["The supercritical carbon dioxide (SC0₂) power conversion system has been suggested for use with many of the Generation IV nuclear reactors. The SC0₂ cycle is highly attractive because of its low operating temperatures and high efficiency associated with working near the critical point of CO2. Unfortunately, the appealing features of using C0₂ near its critical point create complications in control. The Transient SC0₂ Cycles Code (TSCYCO) has been developed as a transient simulation control design and cycle scoping code for the recompression SC0₂ Brayton cycle. It is based off of the SC0₂ Power Systems (SCPS) code, and incorporates many improvements and modifications. Written in FORTRAN 90, TSCYCO uses a lumped parameter model and a momentum integral model approach. The code uses a semi-implicit solution process and implements Gaussian elimination to solve the system of equations. Transient behavior of the printed circuit heat exchangers is determined via the previously developed code HXMOD. Turbomachinery performance is modeled using the Real Gas Radial Compressor (RGRC) code with a scaling scheme for off-design conditions. Currently, TSCYCO has the capability of modeling several transients, including: loss of external load (LOEL), power load change, and cycle low-temperature change. Simulations show that TSCYCO can be run at quasi-steady state for an indefinite period of time. In the case of a 10% LOEL, the axial turbine experiences choke as a result of shaft overspeed. Turbine choke can be avoided if one bypasses more flow during LOEL.","(cont.) Moreover, one can incorporate more accurate axial turbine performance models to account for shaft speed variation. TSCYCO experiences instabilities when operated too closely to the critical point of C0₂. This could be remedied with a more robust Runge-Kutta solution method."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["S.M."]},{"key":"dc:title","label":"Title","values":["Dynamic response of the supercritical C0₂ Brayton recompression cycle to various system transients"]}]}],"canonical_facts":{"dc:contributor.advisor":["Pavel Hejzlar and Michael Driscoll."],"dc:contributor.department":["Massachusetts Institute of Technology. Dept. of Nuclear Science and Engineering."],"dc:contributor.other":["Massachusetts Institute of Technology. Dept. of Nuclear Science and Engineering."],"dc:creator":["Trinh, Tri Q. (Tri Quang)"],"dc:date.accessioned":["2010-04-07T13:05:32Z"],"dc:date.available":["2010-04-07T13:05:32Z"],"dc:date.issued":["2009"],"dc:description":["Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Nuclear Science and Engineering, 2009.","Page 208 blank. Cataloged from PDF version of thesis.","Includes bibliographical references (p. 159-160)."],"dc:description.abstract":["The supercritical carbon dioxide (SC0₂) power conversion system has been suggested for use with many of the Generation IV nuclear reactors. The SC0₂ cycle is highly attractive because of its low operating temperatures and high efficiency associated with working near the critical point of CO2. Unfortunately, the appealing features of using C0₂ near its critical point create complications in control. The Transient SC0₂ Cycles Code (TSCYCO) has been developed as a transient simulation control design and cycle scoping code for the recompression SC0₂ Brayton cycle. It is based off of the SC0₂ Power Systems (SCPS) code, and incorporates many improvements and modifications. Written in FORTRAN 90, TSCYCO uses a lumped parameter model and a momentum integral model approach. The code uses a semi-implicit solution process and implements Gaussian elimination to solve the system of equations. Transient behavior of the printed circuit heat exchangers is determined via the previously developed code HXMOD. Turbomachinery performance is modeled using the Real Gas Radial Compressor (RGRC) code with a scaling scheme for off-design conditions. Currently, TSCYCO has the capability of modeling several transients, including: loss of external load (LOEL), power load change, and cycle low-temperature change. Simulations show that TSCYCO can be run at quasi-steady state for an indefinite period of time. In the case of a 10% LOEL, the axial turbine experiences choke as a result of shaft overspeed. Turbine choke can be avoided if one bypasses more flow during LOEL.","(cont.) Moreover, one can incorporate more accurate axial turbine performance models to account for shaft speed variation. TSCYCO experiences instabilities when operated too closely to the critical point of C0₂. This could be remedied with a more robust Runge-Kutta solution method."],"dc:description.degree":["S.M."],"dc:identifier.uri":["http://hdl.handle.net/1721.1/53527"],"dc:language.iso":["eng"],"dc:publisher":["Massachusetts Institute of Technology"],"dc:rights":["M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission."],"dc:rights.uri":["http://dspace.mit.edu/handle/1721.1/7582"],"dc:subject":["Nuclear Science and Engineering."],"dc:title":["Dynamic response of the supercritical C0₂ Brayton recompression cycle to various system transients"],"dc:type":["Thesis"]},"updated_at":"2026-07-22T22:21:36Z"}