Experimental and numerical study of cap-like lean limit flames in H 2 -CH 4 -air mixtures

Handle URI:
http://hdl.handle.net/10754/626178
Title:
Experimental and numerical study of cap-like lean limit flames in H 2 -CH 4 -air mixtures
Authors:
Zhou, Zhen; Shoshin, Yuriy; Hernandez Perez, Francisco; van Oijen, Jeroen A.; de Goey, Laurentius P.H. ( 0000-0001-6625-3113 )
Abstract:
Lean limit flames of H2-CH4-air mixtures stabilized inside a tube with an inner diameter of 30 mm in a downward flow are studied experimentally and numerically. A transition from bubble-like flames, with a long decaying skirt, to cap-like flames with a sharp visible flame edge at the bottom is observed as the lean flammability limit is approached. This transition is accompanied by formation of a secondary weak flame front inside the cap-like flame. The CH* chemiluminescence distribution of the studied flames is recorded and the velocity field of the lean limit flames is measured using Particle Image Velocimetry (PIV). The flame temperature field is measured utilizing the Rayleigh scattering method. Numerical prediction with a mixture-averaged transport model and skeletal mechanism for CH4 qualitatively reproduces the above experimentally observed phenomena. The presence of negative flame displacement speed for the entire leading edge of the cap-like flames is numerically predicted and experimentally demonstrated. The secondary weak flame front is located in a region with reverse upward flow of the recirculation zone, which is found to support the propagation of the leading edge with a negative flame displacement speed. Furthermore, radiative heat loss has a significant influence on the lean flammability limit of the cap-like flames.
KAUST Department:
Clean Combustion Research Center
Citation:
Zhou Z, Shoshin Y, Hernández-Pérez FE, van Oijen JA, de Goey LPH (2018) Experimental and numerical study of cap-like lean limit flames in H 2 -CH 4 -air mixtures. Combustion and Flame 189: 212–224. Available: http://dx.doi.org/10.1016/j.combustflame.2017.10.031.
Publisher:
Elsevier BV
Journal:
Combustion and Flame
Issue Date:
15-Nov-2017
DOI:
10.1016/j.combustflame.2017.10.031
Type:
Article
ISSN:
0010-2180
Sponsors:
The financial support of the Dutch Technology Foundation (STW), Project 13549, is gratefully acknowledged. The authors thank Prof. Clinton Groth for providing access to the CFFC (Computational Framework for Fluids and Combustion) code.
Additional Links:
http://www.sciencedirect.com/science/article/pii/S0010218017304285
Appears in Collections:
Articles; Clean Combustion Research Center

Full metadata record

DC FieldValue Language
dc.contributor.authorZhou, Zhenen
dc.contributor.authorShoshin, Yuriyen
dc.contributor.authorHernandez Perez, Franciscoen
dc.contributor.authorvan Oijen, Jeroen A.en
dc.contributor.authorde Goey, Laurentius P.H.en
dc.date.accessioned2017-11-20T12:48:14Z-
dc.date.available2017-11-20T12:48:14Z-
dc.date.issued2017-11-15en
dc.identifier.citationZhou Z, Shoshin Y, Hernández-Pérez FE, van Oijen JA, de Goey LPH (2018) Experimental and numerical study of cap-like lean limit flames in H 2 -CH 4 -air mixtures. Combustion and Flame 189: 212–224. Available: http://dx.doi.org/10.1016/j.combustflame.2017.10.031.en
dc.identifier.issn0010-2180en
dc.identifier.doi10.1016/j.combustflame.2017.10.031en
dc.identifier.urihttp://hdl.handle.net/10754/626178-
dc.description.abstractLean limit flames of H2-CH4-air mixtures stabilized inside a tube with an inner diameter of 30 mm in a downward flow are studied experimentally and numerically. A transition from bubble-like flames, with a long decaying skirt, to cap-like flames with a sharp visible flame edge at the bottom is observed as the lean flammability limit is approached. This transition is accompanied by formation of a secondary weak flame front inside the cap-like flame. The CH* chemiluminescence distribution of the studied flames is recorded and the velocity field of the lean limit flames is measured using Particle Image Velocimetry (PIV). The flame temperature field is measured utilizing the Rayleigh scattering method. Numerical prediction with a mixture-averaged transport model and skeletal mechanism for CH4 qualitatively reproduces the above experimentally observed phenomena. The presence of negative flame displacement speed for the entire leading edge of the cap-like flames is numerically predicted and experimentally demonstrated. The secondary weak flame front is located in a region with reverse upward flow of the recirculation zone, which is found to support the propagation of the leading edge with a negative flame displacement speed. Furthermore, radiative heat loss has a significant influence on the lean flammability limit of the cap-like flames.en
dc.description.sponsorshipThe financial support of the Dutch Technology Foundation (STW), Project 13549, is gratefully acknowledged. The authors thank Prof. Clinton Groth for providing access to the CFFC (Computational Framework for Fluids and Combustion) code.en
dc.publisherElsevier BVen
dc.relation.urlhttp://www.sciencedirect.com/science/article/pii/S0010218017304285en
dc.rightsNOTICE: this is the author’s version of a work that was accepted for publication in Combustion and Flame. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Combustion and Flame, [, , (2017-11-15)] DOI: 10.1016/j.combustflame.2017.10.031 . © 2017. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/en
dc.subjectLow Lewis numberen
dc.subjectLean combustion limiten
dc.subjectNegative flame displacement speeden
dc.subjectCap-like flameen
dc.titleExperimental and numerical study of cap-like lean limit flames in H 2 -CH 4 -air mixturesen
dc.typeArticleen
dc.contributor.departmentClean Combustion Research Centeren
dc.identifier.journalCombustion and Flameen
dc.eprint.versionPost-printen
dc.contributor.institutionDepartment of Mechanical Engineering, Eindhoven University of Technology, P.O. Box 513, Eindhoven 5600MB, The Netherlandsen
kaust.authorHernandez Perez, Franciscoen
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