NOTICE: Due to a lapse in annual appropriations, most of this website is not being updated. Learn more.
Form submissions will still be accepted but will not receive responses at this time. Sections of this site for programs using non-appropriated funds (such as NVLAP) or those that are excepted from the shutdown (such as CHIPS and NVD) will continue to be updated.
An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
The Existence of Precursor Soot in the Exhaust of Inverse Diffusion Flames
Published
Author(s)
L G. Blevins, Robert A. Fletcher, Bruce A. Benner Jr, Eric B. Steel, George W. Mulholland
Abstract
Knowledge of the chemical and physical structure of precursor soot is useful in the development of soot particle inception models. This paper examines the hypothesis that soot exiting an inverse flame is similar in chemical and morphological structure to (1) young precursor soot and (2) soot that exits underventilated flames. Experiments involving soot collection from the exhaust of laminar ethylene inverse diffusion flames were performed. Soot samples were analyzed for morphology, carbon-to-hydrogen ratio, organic fraction, and polycyclic aromatic hydrocarbon content. Results of these analyses prove the validity of the above hypothesis. This finding is significant because exhaust collection from the inverse flame provides an opportunity to gather large precursor soot samples without invading the flame with an intrusive probe (a necessary task when collecting precursors low in the center of a normal diffusion flame). Larger samples can then be subjected to more detailed analysis than previously possible.
Citation
Proceedings of the Combustion Institute
Volume
29
Pub Type
Journals
Keywords
carbon-to-hydrogen ratio, gas chromatography/mass spectroscopy, inverse diffusion flame, laser microprobe mass spectrometer, polycyclic aromatic hydrocarbon, precursor soot, transmission electron microscopy
Blevins, L.
, Fletcher, R.
, Benner, B.
, Steel, E.
and Mulholland, G.
(2002),
The Existence of Precursor Soot in the Exhaust of Inverse Diffusion Flames, Proceedings of the Combustion Institute
(Accessed October 6, 2025)