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Author
Ogawa, Y.
Title
Effect of Interaction Between Halogenated Fire Suppressants and Inert Gases on the Extinction Limit of Premixed Flames.
Coporate
National Research Institute of Fire and Disaster, Tokyo, Japan
Report
BFRL Seminar, March 27, 1997,
Keywords
premixed flames | inert gases
Abstract
A synergistic effect betwen halon 1301 and inert gases was found in previous studies of flame suppression efficiency using a cup burner diffusion flame. Further Experiments using a variety of suppressants in premixed tubular flames (methane/air) were performed in order to better understand the causes of this effect. The halogenated suppressants considered,in addition to halon 130 were: tetrafluoromethane, HFC-23, HFC-227ea and FC-3-1-10. The synergistic effects in halon 1301/nitrogen and concentrations of the suppressant at the limit of extinction were measured. The maximum synergy between halon 1301 and nitrogen was observed for a mixture consisting of 10% halon 1301 and 90% nitrogen (by mole). The effect is most pronounced at stoichiometric conditions. A negative synergy was observed for binary mixtures of nitrogen with each of the following suppressants: HFC-23, HFC227ea and FC-3-1-10. The presence of nitrogen, however had no effect the experimental extinction limits of the methane/air flames by tetrafluoromethane.