The use of CO 2 as an additive for ignition delay and pollutant control in CH 4 /air autoignition

Handle URI:
http://hdl.handle.net/10754/626031
Title:
The use of CO 2 as an additive for ignition delay and pollutant control in CH 4 /air autoignition
Authors:
Tingas, Efstathios Al.; Im, Hong G. ( 0000-0001-7080-1266 ) ; Kyritsis, Dimitrios C.; Goussis, Dimitris A.
Abstract:
The effect of CO2 dilution on the adiabatic and isochoric autoignition of CH4/air mixtures is analyzed with Computational Singular Perturbation (CSP) algorithmic tools, with a particular emphasis on the determination of the features of the chemical dynamics that control ignition delay and emission formation. Increasing CO2 dilution causes longer ignition delays, lower final temperatures and decreased formation of NO and CO. These effects of CO2 dilution are shown to be entirely thermal, contrary to what happens with dilution with H2O, which also has chemical activity and can reduce ignition delay. For the same initial mole fraction of the diluent, the decrease in final temperature and in NO concentration is larger in the CO2 case whereas the decrease in CO is larger in the H2O case. The thermal effect of CO2 is entirely analogous with those of dilution with the chemically inert Ar, only stronger for the same percentage of initial dilution, because of the larger specific heat of CO2. The reactions that have the largest contribution to the characteristic explosive time scale of the system during ignition delay (H2O2(+M)→OH+OH(+M), CH3O2+CH2O→CH3O2H+HCO, CH4+CH3O2→CH3+CH3O2H, H+O2→O+OH, etc.) are not substantially affected by CO2 dilution, neither are the species that are pointed by CSP (CH3O2, H2O2, CH2O, etc.) as having the largest impact on the this timescale. The same holds for the modes that control CO and NO formation. The results point to the possibility of cold exhaust gas recirculation being used in order to produce mixtures with longer ignition delays and therefore substantial resistance to uncontrolled ignition.
KAUST Department:
Clean Combustion Research Center
Citation:
Tingas EA, Im HG, Kyritsis DC, Goussis DA (2018) The use of CO 2 as an additive for ignition delay and pollutant control in CH 4 /air autoignition. Fuel 211: 898–905. Available: http://dx.doi.org/10.1016/j.fuel.2017.09.022.
Publisher:
Elsevier BV
Journal:
Fuel
Issue Date:
5-Oct-2017
DOI:
10.1016/j.fuel.2017.09.022
Type:
Article
ISSN:
0016-2361
Sponsors:
EAT, HGI, and DAG would like to acknowledge sponsorship by competitive research funding from King Abdullah University of Science and Technology (KAUST).
Additional Links:
http://www.sciencedirect.com/science/article/pii/S001623611731133X
Appears in Collections:
Articles; Clean Combustion Research Center

Full metadata record

DC FieldValue Language
dc.contributor.authorTingas, Efstathios Al.en
dc.contributor.authorIm, Hong G.en
dc.contributor.authorKyritsis, Dimitrios C.en
dc.contributor.authorGoussis, Dimitris A.en
dc.date.accessioned2017-10-30T08:39:51Z-
dc.date.available2017-10-30T08:39:51Z-
dc.date.issued2017-10-05en
dc.identifier.citationTingas EA, Im HG, Kyritsis DC, Goussis DA (2018) The use of CO 2 as an additive for ignition delay and pollutant control in CH 4 /air autoignition. Fuel 211: 898–905. Available: http://dx.doi.org/10.1016/j.fuel.2017.09.022.en
dc.identifier.issn0016-2361en
dc.identifier.doi10.1016/j.fuel.2017.09.022en
dc.identifier.urihttp://hdl.handle.net/10754/626031-
dc.description.abstractThe effect of CO2 dilution on the adiabatic and isochoric autoignition of CH4/air mixtures is analyzed with Computational Singular Perturbation (CSP) algorithmic tools, with a particular emphasis on the determination of the features of the chemical dynamics that control ignition delay and emission formation. Increasing CO2 dilution causes longer ignition delays, lower final temperatures and decreased formation of NO and CO. These effects of CO2 dilution are shown to be entirely thermal, contrary to what happens with dilution with H2O, which also has chemical activity and can reduce ignition delay. For the same initial mole fraction of the diluent, the decrease in final temperature and in NO concentration is larger in the CO2 case whereas the decrease in CO is larger in the H2O case. The thermal effect of CO2 is entirely analogous with those of dilution with the chemically inert Ar, only stronger for the same percentage of initial dilution, because of the larger specific heat of CO2. The reactions that have the largest contribution to the characteristic explosive time scale of the system during ignition delay (H2O2(+M)→OH+OH(+M), CH3O2+CH2O→CH3O2H+HCO, CH4+CH3O2→CH3+CH3O2H, H+O2→O+OH, etc.) are not substantially affected by CO2 dilution, neither are the species that are pointed by CSP (CH3O2, H2O2, CH2O, etc.) as having the largest impact on the this timescale. The same holds for the modes that control CO and NO formation. The results point to the possibility of cold exhaust gas recirculation being used in order to produce mixtures with longer ignition delays and therefore substantial resistance to uncontrolled ignition.en
dc.description.sponsorshipEAT, HGI, and DAG would like to acknowledge sponsorship by competitive research funding from King Abdullah University of Science and Technology (KAUST).en
dc.publisherElsevier BVen
dc.relation.urlhttp://www.sciencedirect.com/science/article/pii/S001623611731133Xen
dc.subjectAutoignitionen
dc.subjectNOen
dc.subjectMethaneen
dc.subjectCSPen
dc.titleThe use of CO 2 as an additive for ignition delay and pollutant control in CH 4 /air autoignitionen
dc.typeArticleen
dc.contributor.departmentClean Combustion Research Centeren
dc.identifier.journalFuelen
dc.contributor.institutionDepartment of Mechanical Engineering, Khalifa University of Science and Technology, 127788 Abu Dhabi, United Arab Emiratesen
dc.contributor.institutionDepartment of Mechanics, School of Applied Mathematical and Physical Sciences, National Technical University, 15780 Athens, Greeceen
kaust.authorTingas, Efstathios Al.en
kaust.authorIm, Hong G.en
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