Effect of the methyl substitution on the combustion of two methylheptane isomers: Flame chemistry using vacuum-ultraviolet (VUV) photoionization mass spectrometry

Handle URI:
http://hdl.handle.net/10754/564143
Title:
Effect of the methyl substitution on the combustion of two methylheptane isomers: Flame chemistry using vacuum-ultraviolet (VUV) photoionization mass spectrometry
Authors:
Selim, Hatem; Mohamed, Samah; Lucassen, Arnas; Hansen, Nils; Sarathy, Mani ( 0000-0002-3975-6206 )
Abstract:
Alkanes with one or more methyl substitutions are commonly found in liquid transportation fuels, so a fundamental investigation of their combustion chemistry is warranted. In the present work, stoichiometric low-pressure (20 Torr) burner-stabilized flat flames of 2-methylheptane and 3-methylheptane were investigated. Flame species were measured via time-of-flight molecular-beam mass spectrometry, with vacuum-ultraviolet (VUV) synchrotron radiation as the ionization source. Mole fractions of major end-products and intermediate species (e.g., alkanes, alkenes, alkynes, aldehydes, and dienes) were quantified axially above the burner surface. Mole fractions of several free radicals were also measured (e.g., CH3, HCO, C2H3, C3H3, and C3H5). Isomers of different species were identified within the reaction pool by an energy scan between 8 and 12 eV at a distance of 2.5 mm away from the burner surface. The role of methyl substitution location on the alkane chain was determined via comparisons of similar species trends obtained from both flames. The results revealed that the change in CH3 position imposed major differences on the combustion of both fuels. Comparison with numerical simulations was performed for kinetic model testing. The results provide a comprehensive set of data about the combustion of both flames, which can enhance the erudition of both fuels combustion chemistry and also improve their chemical kinetic reaction mechanisms. © 2015 American Chemical Society.
KAUST Department:
Clean Combustion Research Center; Chemical and Biological Engineering Program; Physical Sciences and Engineering (PSE) Division
Publisher:
American Chemical Society (ACS)
Journal:
Energy & Fuels
Issue Date:
16-Apr-2015
DOI:
10.1021/ef502797a
Type:
Article
ISSN:
08870624
Sponsors:
The authors acknowledge funding support from the Clean Combustion Research Center and from Saudi Aramco, under the FUELCOM program. The measurements were performed within the "Flame Team" collaboration at the Advanced Light Source (ALS), Lawrence Berkeley National Laboratory, Berkeley, USA, and we thank the students and postdocs for the help with the data acquisition. The experiments at the Advanced Light Source (ALS) have profited from the expert technical assistance of Paul Fugazzi. The ALS is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy, under Contract No. DEAC02-05CH11231. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the National Nuclear Security Administration under Contract No. DE-AC04-94-AL85000.
Appears in Collections:
Articles; Physical Sciences and Engineering (PSE) Division; Chemical and Biological Engineering Program; Clean Combustion Research Center

Full metadata record

DC FieldValue Language
dc.contributor.authorSelim, Hatemen
dc.contributor.authorMohamed, Samahen
dc.contributor.authorLucassen, Arnasen
dc.contributor.authorHansen, Nilsen
dc.contributor.authorSarathy, Manien
dc.date.accessioned2015-08-03T12:33:56Zen
dc.date.available2015-08-03T12:33:56Zen
dc.date.issued2015-04-16en
dc.identifier.issn08870624en
dc.identifier.doi10.1021/ef502797aen
dc.identifier.urihttp://hdl.handle.net/10754/564143en
dc.description.abstractAlkanes with one or more methyl substitutions are commonly found in liquid transportation fuels, so a fundamental investigation of their combustion chemistry is warranted. In the present work, stoichiometric low-pressure (20 Torr) burner-stabilized flat flames of 2-methylheptane and 3-methylheptane were investigated. Flame species were measured via time-of-flight molecular-beam mass spectrometry, with vacuum-ultraviolet (VUV) synchrotron radiation as the ionization source. Mole fractions of major end-products and intermediate species (e.g., alkanes, alkenes, alkynes, aldehydes, and dienes) were quantified axially above the burner surface. Mole fractions of several free radicals were also measured (e.g., CH3, HCO, C2H3, C3H3, and C3H5). Isomers of different species were identified within the reaction pool by an energy scan between 8 and 12 eV at a distance of 2.5 mm away from the burner surface. The role of methyl substitution location on the alkane chain was determined via comparisons of similar species trends obtained from both flames. The results revealed that the change in CH3 position imposed major differences on the combustion of both fuels. Comparison with numerical simulations was performed for kinetic model testing. The results provide a comprehensive set of data about the combustion of both flames, which can enhance the erudition of both fuels combustion chemistry and also improve their chemical kinetic reaction mechanisms. © 2015 American Chemical Society.en
dc.description.sponsorshipThe authors acknowledge funding support from the Clean Combustion Research Center and from Saudi Aramco, under the FUELCOM program. The measurements were performed within the "Flame Team" collaboration at the Advanced Light Source (ALS), Lawrence Berkeley National Laboratory, Berkeley, USA, and we thank the students and postdocs for the help with the data acquisition. The experiments at the Advanced Light Source (ALS) have profited from the expert technical assistance of Paul Fugazzi. The ALS is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy, under Contract No. DEAC02-05CH11231. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the National Nuclear Security Administration under Contract No. DE-AC04-94-AL85000.en
dc.publisherAmerican Chemical Society (ACS)en
dc.titleEffect of the methyl substitution on the combustion of two methylheptane isomers: Flame chemistry using vacuum-ultraviolet (VUV) photoionization mass spectrometryen
dc.typeArticleen
dc.contributor.departmentClean Combustion Research Centeren
dc.contributor.departmentChemical and Biological Engineering Programen
dc.contributor.departmentPhysical Sciences and Engineering (PSE) Divisionen
dc.identifier.journalEnergy & Fuelsen
dc.contributor.institutionCombustion Research Facility, Sandia National LaboratoriesLivermore, CA, United Statesen
dc.contributor.institutionDepartment for Thermophysical Quantities, Physikalisch Technische Bundesanstalt (PTB)Braunschweig, Germanyen
kaust.authorSelim, Hatemen
kaust.authorSarathy, Manien
kaust.authorMohamed, Samahen
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