Experimental investigation of flame pattern transitions in a heated radial micro-channel

Aiwu Fan, Kaoru Maruta, Hisashi Nakamura, Wei Liu

Research output: Contribution to journalArticlepeer-review

21 Citations (Scopus)

Abstract

Flame pattern transitions of CH 4/air mixture were experimentally investigated in a radial micro-channel. These transitions were triggered by a variation in the mixture equivalence ratio or inlet mixture velocity. The transition processes were recorded with a high-speed digital video camera. From the movies, it is shown that the mechanisms responsible for these transitions could be classified into two: (1) transitions from a stable circular flame to a traveling flame, and from a traveling flame to single or double Pelton-like flames were due to local extinction in the flame front, and (2) transition from an unstable circular flame to a spiral-like flame was due to local splitting of the flame front. Numerical simulation of the isothermal flow demonstrated that flow field is symmetric and steady when the inlet velocity is small, but it grows asymmetric and unstable at large inlet velocities. The asymmetric and unstable flow field is expected to be the possible reason for the local splitting of flame front. On the other hand, flame is noted to be quenched near the top wall surface. These two reasons are expected to induce the transition from an unstable flame to a rotating spiral-like flame.

Original languageEnglish
Pages (from-to)111-118
Number of pages8
JournalApplied Thermal Engineering
Volume47
DOIs
Publication statusPublished - 2012 Dec 5

Keywords

  • Flame pattern transition
  • Flow instability
  • Local extinction
  • Local splitting
  • Micro-combustion

ASJC Scopus subject areas

  • Energy Engineering and Power Technology
  • Industrial and Manufacturing Engineering

Fingerprint Dive into the research topics of 'Experimental investigation of flame pattern transitions in a heated radial micro-channel'. Together they form a unique fingerprint.

Cite this