An experimental and numerical study of the effects of dimethyl ether addition to fuel on polycyclic aromatic hydrocarbon and soot formation in laminar coflow ethylene/air diffusion flames

Download
  1. Get@NRC: An experimental and numerical study of the effects of dimethyl ether addition to fuel on polycyclic aromatic hydrocarbon and soot formation in laminar coflow ethylene/air diffusion flames (Opens in a new window)
DOIResolve DOI: http://doi.org/10.1016/j.combustflame.2010.10.005
AuthorSearch for: ; Search for: ; Search for: ; Search for: ; Search for: ; Search for: ; Search for: ; Search for: ; Search for:
TypeArticle
Journal titleCombustion and Flame
ISSN0010-2180
Volume158
Issue3
Pages547563; # of pages: 17
SubjectLaminar diffusion flames; Numerical modeling; PAHs; Soot formation; Synergistic effect; Acetylene; Addition reactions; Aromatization; Atmospheric pressure; Benzene; Coagulation; Diffusion; Dust; Ethers; Ethylene; Experiments; Fuels; Hydraulics; Numerical methods; Organic compounds; Polycyclic aromatic hydrocarbons; Soot; Ternary systems; Titration; Aromatic hydrocarbons; acetylene; benzene; dimethyl ether; ethylene; fuel; polycyclic aromatic hydrocarbon; pyrene; air; analytic method; article; atmospheric pressure; chemical reaction kinetics; diffusion; flame; flow rate; laminar flow; laser; physical parameters; priority journal; quantitative study; soot; temperature
AbstractThe effects of dimethyl ether addition to fuel on the formation of polycyclic aromatic hydrocarbons and soot were investigated experimentally and numerically in a laminar coflow ethylene diffusion flame at atmospheric pressure. The relative concentrations of polycyclic aromatic hydrocarbon species and the relative soot volume fractions were measured using planar laser-induced fluorescence and two-dimensional laser-induced incandescence techniques, respectively. Experiments were conducted over the entire range of dimethyl ether addition from pure ethylene to pure dimethyl ether in the fuel stream. The total carbon mass flow rate was maintained constant when the fraction of DME in the fuel stream was varied. Numerical calculations of nine diffusion flames of different dimethyl ether fractions in the fuel stream were performed using a detailed reaction mechanism consisting of 151 species and 785 reactions and a sectional soot model including soot radiation, inception of nascent soot particle due to collision of two pyrene molecules, heterogeneous surface growth and oxidation following the hydrogen abstraction acetylene addition mechanism, soot particle coagulation, and PAH surface condensation. The addition of a relatively small amount of dimethyl ether to ethylene was found experimentally to increase the concentrations of both polycyclic aromatic hydrocarbons and soot. The synergistic effect on polycyclic aromatic hydrocarbons persists over a wider range of dimethyl ether addition. The numerical results reproduce the synergistic effects of dimethyl ether addition to ethylene on both polycyclic aromatic hydrocarbons and soot, though the magnitude of soot volume fraction overshoot and the range of dimethyl ether addition associated with the synergistic effect of soot are less than those observed in the experiment. The synergistic effects of dimethyl ether addition to ethylene on many hydrocarbon species, including polycyclic aromatic ones, and soot can be fundamentally traced to the enhanced methyl concentration with the addition of dimethyl ether to ethylene. Contrary to previous findings, the pathways responsible for the synergistic effects of benzene, polycyclic aromatic hydrocarbons, and soot in the ethylene/dimethyl ether system are found to be primarily due to the cyclization of l-C6H6 and n-C6H7 and to a much lesser degree due to the interaction between C2 and C4 species for benzene formation, rather than the propargyl self-combination reaction route, though it is indeed the most important reaction for the formation of benzene. © 2010.
Publication date
LanguageEnglish
AffiliationNational Research Council Canada (NRC-CNRC); NRC Institute for Chemical Process and Environmental Technology (ICPET-ITPCE)
Peer reviewedYes
NPARC number21271190
Export citationExport as RIS
Report a correctionReport a correction
Record identifier0f0cf570-03a5-4f29-989c-57d0224e1dec
Record created2014-03-24
Record modified2016-05-09
Bookmark and share
  • Share this page with Facebook (Opens in a new window)
  • Share this page with Twitter (Opens in a new window)
  • Share this page with Google+ (Opens in a new window)
  • Share this page with Delicious (Opens in a new window)