Chemical Limits to Flame Inhibition.
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.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899