Extinction of methane/air counterflow partially premixed flames

Tomoya Wada, Masahiko Mizomoto, Takeshi Yokomori, Norbert Peters

Research output: Contribution to journalArticle

11 Citations (Scopus)

Abstract

Flame interactions of partially premixed flames (PPFs) were experimentally and numerically studied using counterflow configurations with CH4/air mixtures under atmospheric condition. The main aims of this study were to describe the flame interactions in terms of variations in global strain rate (K) and to understand flame extinction. Two premixed-fuel streams were characterized by equivalence ratios (φlean and φrich). Experiments were conducted under the following conditions: φlean + φrich = 2, 0.5 < φlean < 0.7 (i.e., 1.3 < φrich < 1.5), and several K values. To describe the interactions, twin flames (TFs), also examined under corresponding φ, were used as a criterion, because the φ values were within the flammability limits. Experimental results of PPFs showed a different behavior than those of TFs: first, three different luminous layers were observed; second, thin single-layered flames, with a nearly constant flame width, were observed near extinction for several combinations of φ third, PPFs could exist for significantly higher K than TFs. Numerical results supported the experimental results and showed that two reaction paths, CH 4 + OH -→ CH3 + H2O and CH3 + O → CO + H2 + H, were remarkably intensified by flame interaction of PPF near extinction; the significance of the reaction paths was determined. In addition, it was found that excess CO production plays an important role in extinction of PPFs.

Original languageEnglish
Pages (from-to)1075-1082
Number of pages8
JournalProceedings of the Combustion Institute
Volume32 I
DOIs
Publication statusPublished - 2009

Fingerprint

counterflow
premixed flames
Methane
Flammability
Carbon Monoxide
Strain rate
flames
extinction
methane
flame interaction
air
Air
Experiments
flammability
meteorology
strain rate
equivalence
methylidyne
configurations
hydroxide ion

Keywords

  • Extinction
  • Flame stretch
  • Partially premixed flame
  • Premixed flame
  • Triple flame

ASJC Scopus subject areas

  • Mechanical Engineering
  • Chemical Engineering(all)
  • Physical and Theoretical Chemistry

Cite this

Extinction of methane/air counterflow partially premixed flames. / Wada, Tomoya; Mizomoto, Masahiko; Yokomori, Takeshi; Peters, Norbert.

In: Proceedings of the Combustion Institute, Vol. 32 I, 2009, p. 1075-1082.

Research output: Contribution to journalArticle

Wada, Tomoya ; Mizomoto, Masahiko ; Yokomori, Takeshi ; Peters, Norbert. / Extinction of methane/air counterflow partially premixed flames. In: Proceedings of the Combustion Institute. 2009 ; Vol. 32 I. pp. 1075-1082.
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