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Effect of Halogenated Flame Inhibitors on C1-C2 Organic Flames.


pdf icon Effect of Halogenated Flame Inhibitors on C1-C2 Organic Flames. (618 K)
Noto, T.; Babushok, V. I.; Burgess, D. R. F., Jr.; Hamins, A.; Tsang, W.; Miziolek, A. W.

Combustion Institute, Symposium (International) on Combustion, 26th. Proceedings. Volume 1. July 28-August 2, 1996, Napoli, Italy, Combustion Institute, Pittsburgh, PA, 1377-1383 pp, 1996.

Keywords:

combustion; flame extinguishment; flame propagation; kinetics; simulation; validation; burning velocity; temperature effects

Abstract:

The influence of CF3Br, CF3I, CF4, CHF3, C2F6, and C2HF on laminar flame propagation in mixtures of CH4, CH3OH, C2H6, and C2H4 with air has been determined by numerical simulaitons. Comparisons are made with experimental results and earlier calculations. Flame velocities as a function of inhibitor concentration and equivalence ratio have been determined. For all the organic fuels, the ranking of inhibitive efficience is CF3Br, CF3I>C2F6>C3HF5>CHF3>CF4. The bromine and iodine compounds are clearly the ost efficient flame suppressants. They are of equal effectiveness except in methanol, where CF3I is superior. The retardants are more effective for rich mixtures than for lean. With 1% inhibitor concentration, the decrease in burning velocity is most pronounced for unsaturated fuels. The general ordering is consistent with calculational results on flame thickness and radical concentrations. Reaction pathway analysis demonstrates the importance of the regeneration of reactive scavengers. Relative contributions from physical and chemical effects are estimated.