Shock tube and modeling study of 2,7-dimethyloctane pyrolysis and oxidation

Handle URI:
http://hdl.handle.net/10754/566165
Title:
Shock tube and modeling study of 2,7-dimethyloctane pyrolysis and oxidation
Authors:
Li, Sijie; Sarathy, Mani ( 0000-0002-3975-6206 ) ; Davidson, David Frank; Hanson, Ronald Kenneth; Westbrook, Charles K.
Abstract:
High molecular weight iso-paraffinic molecules are found in conventional petroleum, Fischer-Tropsch (FT), and other alternative hydrocarbon fuels, yet fundamental combustion studies on this class of compounds are lacking. In the present work, ignition delay time measurements in 2,7-dimethyloctane/air were carried out behind reflected shock waves using conventional and constrained reaction volume (CRV) methods. The ignition delay time measurements covered the temperature range 666-1216K, pressure range 12-27atm, and equivalence ratio of 0.5 and 1. The ignition delay time temperatures span the low-, intermediate- and high-temperature regimes for 2,7-dimethyloctane (2,7-DMO) oxidation. Clear evidence of negative temperature coefficient behavior was observed near 800K. Fuel time-history measurements were also carried out in pyrolysis experiments in mixtures of 2000ppm 2,7-DMO/argon at pressures near 16 and 35atm, and in the temperature range of 1126-1455K. Based on the fuel removal rates, the overall 2,7-DMO decomposition rate constant can be represented with k =4.47×105 exp(-23.4[kcal/mol]/RT) [1/s]. Ethylene time-history measurements in pyrolysis experiments at 16atm are also provided. The current shock tube dataset was simulated using a novel chemical kinetic model for 2,7-DMO. The reaction mechanism includes comprehensive low- and high-temperature reaction classes with rate constants assigned using established rules. Comparisons between the simulated and experimental data show simulations reproduce the qualitative trends across the entire range of conditions tested. However, the present kinetic modeling simulations cannot quantitatively reproduce a number of experimental data points, and these are analyzed herein.
KAUST Department:
Clean Combustion Research Center
Publisher:
Elsevier BV
Journal:
Combustion and Flame
Issue Date:
May-2015
DOI:
10.1016/j.combustflame.2015.01.027
Type:
Article
ISSN:
00102180
Appears in Collections:
Articles; Clean Combustion Research Center

Full metadata record

DC FieldValue Language
dc.contributor.authorLi, Sijieen
dc.contributor.authorSarathy, Manien
dc.contributor.authorDavidson, David Franken
dc.contributor.authorHanson, Ronald Kennethen
dc.contributor.authorWestbrook, Charles K.en
dc.date.accessioned2015-08-12T09:30:45Zen
dc.date.available2015-08-12T09:30:45Zen
dc.date.issued2015-05en
dc.identifier.issn00102180en
dc.identifier.doi10.1016/j.combustflame.2015.01.027en
dc.identifier.urihttp://hdl.handle.net/10754/566165en
dc.description.abstractHigh molecular weight iso-paraffinic molecules are found in conventional petroleum, Fischer-Tropsch (FT), and other alternative hydrocarbon fuels, yet fundamental combustion studies on this class of compounds are lacking. In the present work, ignition delay time measurements in 2,7-dimethyloctane/air were carried out behind reflected shock waves using conventional and constrained reaction volume (CRV) methods. The ignition delay time measurements covered the temperature range 666-1216K, pressure range 12-27atm, and equivalence ratio of 0.5 and 1. The ignition delay time temperatures span the low-, intermediate- and high-temperature regimes for 2,7-dimethyloctane (2,7-DMO) oxidation. Clear evidence of negative temperature coefficient behavior was observed near 800K. Fuel time-history measurements were also carried out in pyrolysis experiments in mixtures of 2000ppm 2,7-DMO/argon at pressures near 16 and 35atm, and in the temperature range of 1126-1455K. Based on the fuel removal rates, the overall 2,7-DMO decomposition rate constant can be represented with k =4.47×105 exp(-23.4[kcal/mol]/RT) [1/s]. Ethylene time-history measurements in pyrolysis experiments at 16atm are also provided. The current shock tube dataset was simulated using a novel chemical kinetic model for 2,7-DMO. The reaction mechanism includes comprehensive low- and high-temperature reaction classes with rate constants assigned using established rules. Comparisons between the simulated and experimental data show simulations reproduce the qualitative trends across the entire range of conditions tested. However, the present kinetic modeling simulations cannot quantitatively reproduce a number of experimental data points, and these are analyzed herein.en
dc.publisherElsevier BVen
dc.subject2,7-Dimethyloctaneen
dc.subjectEthylene time-historyen
dc.subjectFuel time-historyen
dc.subjectIgnition delay timeen
dc.subjectNTC regionen
dc.titleShock tube and modeling study of 2,7-dimethyloctane pyrolysis and oxidationen
dc.typeArticleen
dc.contributor.departmentClean Combustion Research Centeren
dc.identifier.journalCombustion and Flameen
dc.contributor.institutionDepartment of Mechanical Engineering, Stanford University, Stanford, CA 94305, United Statesen
dc.contributor.institutionLawrence Livermore National Laboratories, Livermore, CA 94551, United Statesen
kaust.authorSarathy, Manien
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