TITLE:
Cold-State Investigation on a Flame Holder
AUTHORS:
Yiqing Du
KEYWORDS:
Flame Holder; Bluff Body; Flame Stability; Coherent Structure; Vortex Shedding
JOURNAL NAME:
Journal of Power and Energy Engineering,
Vol.1 No.7,
November
28,
2013
ABSTRACT:
Slitty bluff body is widely used as a
high-performance flame holder in power industry. To understand the flame
stability mechanism, the evolution of the near wake over a slitty bluff body in
cold state was numerically investigated using the renormalization group (RNG)
k-ε model at Reynolds number of 470,000.
The coherent structure of the near wake was identified by the vortex shedding
simulation. To explain the vortex shedding, a mechanism that single vortex of
large size suddenly immerses two shear layers was proposed. To quantitatively
compare the near wakes at different gap ratio, a vortex shedding character
dimension was first proposed. This character dimension has positive correlation
with flame stability. Particle-image velocimetry (PIV) measurements in a close
wind tunnel were also carried out to confirm the observation from the numerical
study. The evidence shows that the numerical results are of good agreement with
the cold-state experiments.