Reignition Dynamics in Massively Parallel Direct Numerical Simulations of CO/H2 Jet Flames

Hawkes, E. R., Sankaran, R. and Chen, J. H. (2007). Reignition Dynamics in Massively Parallel Direct Numerical Simulations of CO/H2 Jet Flames. In: Peter Jacobs, Tim McIntyre, Matthew Cleary, David Buttsworth, David Mee, Rose Clements, Richard Morgan and Charles Lemckert, 16th Australasian Fluid Mechanics Conference (AFMC). 16th Australasian Fluid Mechanics Conference (AFMC), Gold Coast, Queensland, Australia, (1271-1274). 3-7 December, 2007.

Attached Files (Some files may be inaccessible until you login with your UQ eSpace credentials)
Name Description MIMEType Size Downloads
Hawkes_afmc_16_07.pdf Conference Paper application/pdf 573.35KB 173

Author Hawkes, E. R.
Sankaran, R.
Chen, J. H.
Title of paper Reignition Dynamics in Massively Parallel Direct Numerical Simulations of CO/H2 Jet Flames
Conference name 16th Australasian Fluid Mechanics Conference (AFMC)
Conference location Gold Coast, Queensland, Australia
Conference dates 3-7 December, 2007
Proceedings title 16th Australasian Fluid Mechanics Conference (AFMC)
Place of Publication Brisbane, Australia
Publisher School of Engineering, The University of Queensland
Publication Year 2007
Year available 2007
Sub-type Fully published paper
ISBN 978-1-864998-94-8
Editor Peter Jacobs
Tim McIntyre
Matthew Cleary
David Buttsworth
David Mee
Rose Clements
Richard Morgan
Charles Lemckert
Start page 1271
End page 1274
Total pages 4
Collection year 2007
Language eng
Abstract/Summary Massively parallel three-dimensional DNS of turbulent temporally evolving nonpremixed plane jet flames have been performed with realistic CO/H2 kinetics. Up to 0.5 billion grid points were employed allowing jet Reynolds numbers of 9000 to be attained. Simulations were run on up to 4096 processors and generated more than 30 TB of raw data. New results are presented concerning the extinction and reignition dynamics occurring in these flames. We characterise extinction using a metric based on the total stoichiometric flame surface area having a reacting scalar such as a product or radical species less than a threshold value taken to represent extinction. The motion of edge flames separating extinguished and burning regions of this surface is studied using a massively parallel analysis tool. The joint probability density function of the local edge flame speed relative to the flow and scalar dissipation has been extracted and shows a transition in character as the simulation progresses. The transition is interpreted in the context of the physical mechanisms of extinction and reignition. Along with other evidence it indicates that the mechanism of folding by turbulence of burning regions onto extinguished ones is the dominant reignition mechanism. The effect of the choice of the scalar species, scalar cut-off value, and mixture fraction value used to define extinction is discussed.
Subjects 290501 Mechanical Engineering
Q-Index Code E1
Q-Index Status Provisional Code
Institutional Status Unknown

 
Versions
Version Filter Type
Citation counts: Google Scholar Search Google Scholar
Created: Wed, 19 Dec 2007, 15:10:01 EST by Laura McTaggart on behalf of School of Engineering