Autoignition characteristics of laminar lifted jet flames of pre-vaporized iso-octane in heated coflow air

Handle URI:
http://hdl.handle.net/10754/594241
Title:
Autoignition characteristics of laminar lifted jet flames of pre-vaporized iso-octane in heated coflow air
Authors:
Alnoman, Saeed ( 0000-0002-5362-3629 ) ; Choi, Sang Kyu; Chung, Suk-Ho ( 0000-0001-8782-312X )
Abstract:
The stabilization characteristics of laminar non-premixed jet flames of pre-vaporized iso-octane, one of the primary reference fuels for octane rating, have been studied experimentally in heated coflow air. Non-autoignited and autoignited lifted flames were analyzed. With the coflow air at relatively low initial temperatures below 940 K, an external ignition source was required to stabilize the flame. These lifted flames had tribrachial edge structures and their liftoff heights correlated well with the jet velocity scaled by stoichiometric laminar burning velocity, indicating the importance of the edge propagation speed on flame stabilization. At high initial temperatures over 940 K, the autoignited flames were stabilized without requiring an external ignition source. These autoignited lifted flames exhibited either tribrachial edge structures or mild combustion behaviors depending on the level of fuel dilution. Two distinct transition behaviors were observed in the autoignition regime from a nozzle-attached flame to a lifted tribrachial-edge flame and then to lifted mild combustion as the jet velocity increased at a certain fuel dilution level. The liftoff data of the autoignited flames with tribrachial edges were analyzed based on calculated ignition delay times. Analysis of the experimental data suggested that ignition delay time may be much less sensitive to initial temperature under atmospheric pressure conditions as compared with predictions. © 2015 Elsevier Ltd. All rights reserved.
KAUST Department:
Clean Combustion Research Center
Citation:
Al-Noman SM, Choi SK, Chung SH (2015) Autoignition characteristics of laminar lifted jet flames of pre-vaporized iso-octane in heated coflow air. Fuel 162: 171–178. Available: http://dx.doi.org/10.1016/j.fuel.2015.09.006.
Publisher:
Elsevier BV
Journal:
Fuel
Issue Date:
Dec-2015
DOI:
10.1016/j.fuel.2015.09.006
Type:
Article
ISSN:
0016-2361
Appears in Collections:
Articles; Clean Combustion Research Center

Full metadata record

DC FieldValue Language
dc.contributor.authorAlnoman, Saeeden
dc.contributor.authorChoi, Sang Kyuen
dc.contributor.authorChung, Suk-Hoen
dc.date.accessioned2016-01-19T14:44:10Zen
dc.date.available2016-01-19T14:44:10Zen
dc.date.issued2015-12en
dc.identifier.citationAl-Noman SM, Choi SK, Chung SH (2015) Autoignition characteristics of laminar lifted jet flames of pre-vaporized iso-octane in heated coflow air. Fuel 162: 171–178. Available: http://dx.doi.org/10.1016/j.fuel.2015.09.006.en
dc.identifier.issn0016-2361en
dc.identifier.doi10.1016/j.fuel.2015.09.006en
dc.identifier.urihttp://hdl.handle.net/10754/594241en
dc.description.abstractThe stabilization characteristics of laminar non-premixed jet flames of pre-vaporized iso-octane, one of the primary reference fuels for octane rating, have been studied experimentally in heated coflow air. Non-autoignited and autoignited lifted flames were analyzed. With the coflow air at relatively low initial temperatures below 940 K, an external ignition source was required to stabilize the flame. These lifted flames had tribrachial edge structures and their liftoff heights correlated well with the jet velocity scaled by stoichiometric laminar burning velocity, indicating the importance of the edge propagation speed on flame stabilization. At high initial temperatures over 940 K, the autoignited flames were stabilized without requiring an external ignition source. These autoignited lifted flames exhibited either tribrachial edge structures or mild combustion behaviors depending on the level of fuel dilution. Two distinct transition behaviors were observed in the autoignition regime from a nozzle-attached flame to a lifted tribrachial-edge flame and then to lifted mild combustion as the jet velocity increased at a certain fuel dilution level. The liftoff data of the autoignited flames with tribrachial edges were analyzed based on calculated ignition delay times. Analysis of the experimental data suggested that ignition delay time may be much less sensitive to initial temperature under atmospheric pressure conditions as compared with predictions. © 2015 Elsevier Ltd. All rights reserved.en
dc.publisherElsevier BVen
dc.subjectAutoignitionen
dc.subjectIso-octaneen
dc.subjectLifted flameen
dc.subjectMild combustionen
dc.subjectTribrachial edgeen
dc.titleAutoignition characteristics of laminar lifted jet flames of pre-vaporized iso-octane in heated coflow airen
dc.typeArticleen
dc.contributor.departmentClean Combustion Research Centeren
dc.identifier.journalFuelen
dc.contributor.institutionEnvironmental and Energy Systems Research Division, KOR Institute of Machinery and Materials, Daejeon, South Koreaen
kaust.authorAlnoman, Saeeden
kaust.authorChung, Suk-Hoen
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