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Behaviors of Flame and Flow of Swirling Wake During Fuel Jet Oscillation Due to Acoustic Excitations

Published online by Cambridge University Press:  05 May 2011

M. E. Loretero  and
R. F. Huang
M. E. Loretero*
Affiliation:
Department of Mechanical Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan 10607, R.O.C.
R. F. Huang*
Affiliation:
Department of Mechanical Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan 10607, R.O.C.
*
* Graduate student
** Professor, corresponding author
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Abstract

The flame and flow behaviors along with the fuel jet oscillations of non-premixed and axisymmetric swirling wake during acoustic excitations are studied experimentally. Visual observations on the reaction zones are carried out to identify the flame behaviors. Close-up images at the flame base as well as the whole flame images are captured and discussed. Traditional photography techniques are adopted to illustrate the dimensional characteristics of every flame mode. The central jet oscillations are diagnosed by a two component laser Doppler anemometer. Combined images of the flame and flow are gathered using the laser-light sheet assisted Mie scattering method. Results showed that the short and wide flame which was induced during acoustic forcing is principally because of the severe premixing at the tip of the burner tube. Wake recirculation bubble enhanced premixing at low swirl number while it damped the jet oscillation at higher swirl number. Mechanics of mixing at every flame mode during acoustic excitation are reported and discussed.

Keywords

Reacting swirling wakeAcoustic excitationNon-premixed flameJet oscillations.
Type
Articles
Information
Journal of Mechanics , Volume 26 , Issue 3 , September 2010 , pp. 279 - 286
Copyright
Copyright © The Society of Theoretical and Applied Mechanics, R.O.C. 2010

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