Experimental and modelling studies of the effects of methanol and ethanol addition on the laminar premixed low-pressure n-heptane/toluene flames

Hanjun Xu, Chunde Yao*, Guanglan Xu, Zhandong Wang, Hanfeng Jin

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

54 Scopus citations

Abstract

The effects of methanol and ethanol on a laminar premixed low-pressure (30Torr) n-heptane/toluene flame were investigated by using synchrotron photoionization and molecular-beam mass spectrometry techniques. The overall carbon flux was maintained constant (0.6g/min) and the equivalence ratio was kept at 2.0 for all the tested flames. Mole fraction profiles of major and intermediate species including most aromatic species were derived and compared among the flames. Simulations were performed based a multi-fuels kinetic mechanism, and the predicted concentrations of most flame species agree well with the measured results. The addition of alcohol showed negligible chemical effect on the hydrocarbon fuels decomposition. Meanwhile the formation of aromatic hydrocarbon intermediates, particularly of those that formed at the later stages of reaction zone, was significantly inhibited. The kinetic study shows that massive HO2 and OH radicals are induced by alcohol addition at the intermediate-temperature region. Thus, the rate of toluene consumption through hydrogen abstraction increases at this region. For this reason as well as that toluene is partially replaced by alcohol fuels, the toluene consumption rate decreases in the followed high-temperature polycyclic aromatic hydrocarbons (PAHs) formation region, which leads to the more significant decrease in PAHs production rates due to the amplification effect of combination reactions in PAHs formation. Such phenomenon indicates that the introduction of alcohol could significantly restrain the formation of aromatic hydrocarbons.

Original languageEnglish (US)
Pages (from-to)1333-1344
Number of pages12
JournalCombustion and Flame
Volume160
Issue number8
DOIs
StatePublished - Aug 2013

Keywords

  • Diesel
  • Ethanol
  • Laminar premixed flame
  • Methanol
  • N-Heptane
  • Toluene

ASJC Scopus subject areas

  • Chemistry(all)
  • Chemical Engineering(all)
  • Fuel Technology
  • Energy Engineering and Power Technology
  • Physics and Astronomy(all)

Fingerprint

Dive into the research topics of 'Experimental and modelling studies of the effects of methanol and ethanol addition on the laminar premixed low-pressure n-heptane/toluene flames'. Together they form a unique fingerprint.

Cite this