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Chemical Limits to Flame Inhibition.


pdf icon Chemical Limits to Flame Inhibition. (857 K)
Babushok, V. I.; Tsang, W.; Linteris, G. T.; Reinelt, D.

Chemical and Physical Processes in Combustion. Fall Technical Meeting, 1996. Proceedings. Combustion Institute/Eastern States Section. December 9-11, 1996, Hilton Head, SC, 265-368 pp, 1998.

Combustion and Flame, Vol. 115, No. 4, 551-560, December 1998.

Keywords:

flame extinguishment; combustion; kinetics; burning velocity

Abstract:

This paper deals with the ultimate limits of chemical contributions to flame inhibition. Particular attention is focussed on the inhibition cycles which regenerate the inhibitor. This leads to the definition of an idealized "perfect" inhibition cycle. It is demonstrated that for such an inhibitor in a stoichiometric methane/air flame, additive levels in the 0.001-0.01 mole percent range will lead to a decrease in flame velocity of approximately 30%. This efficiency corresponds roughly to the observed behavior of metallic inhibitors such as iron pentacarbonyl which is known to be as much as 2 orders of magnitude more effective than currently used suppressants. This correspondence between the behavior of a "perfect inhibitor" and iron carbonyl leads to the conclusion that only gas-phase proesses can account for its inhibitive power.