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Computations of Enhanced Soot Production in Flickering Diffusion Flames.
Published
Author(s)
K C. Smyth, C R. Shaddix, C R. Kaplan
Abstract
Recent experimental measurements of soot volume fraction in a flickering CH4/air diffusion flame show that for conditions in which the tip of the flame is clipped, soot production is ~5 times greater than that measured for a steady flame burning with the same mean fuel flow velocity. Numerical simulations of both steady and time-varying flickering CH4/air diffusion flames are used to examine the differences in combustion conditions which lead to this observed enhancement in soot production in the flickering flames. These simulations successfully predict that the maximum soot concentration increases by over four times compared to the steady flame and show that flickering flames exhibit much longer residence times during which the local temperatures and stoichiometries are favorable for soot production.
Proceedings Title
U.S./Japan Government Cooperative Program on Natural Resources (UJNR). Fire Research and Safety. 13th Joint Panel Meeting. Volume 2
fire safety, fire research, soot, diffusion flames, simulation
Citation
Smyth, K.
, Shaddix, C.
and Kaplan, C.
(1996),
Computations of Enhanced Soot Production in Flickering Diffusion Flames., U.S./Japan Government Cooperative Program on Natural Resources (UJNR). Fire Research and Safety. 13th Joint Panel Meeting. Volume 2, Gaithersburg, MD, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=916995
(Accessed October 28, 2025)