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Fluid Dynamics of Agent Discharge.

pdf icon Fluid Dynamics of Agent Discharge. (14689 K)
Pitts, W. M.; Yang, J. C.; Gmurczyk, G. W.; Cooper, L. Y.; Grosshandler, W. L.; Cleveland, W. G.; Presser, C.

NIST SP 861; April 1994.

Evaluation of Alternative In-Flight Fire Suppressants for Full-Scale Testing in Simulated Aircraft Engine Nacelles and Dry Bays. Section 3, Grosshandler, W. L.; Gann, R. G.; Pitts, W. M., Editor(s)(s), 37-343 pp, 1994.

Available from:

Government Printing Office
Order number: SN003-003-03268-9


halons; fluid dynamics; discharge rate; dispersions; equations; sprays


The extinguishment of a fire using gaseous agents is a very complicated process which is not completely understood. Current fire-fighting agents such as halon 1301 and halon 1211 are believed to function by a combination of chemical (catalytic removal of hydrogen atoms at the flame front due to the presence of bromine atoms) and physical (cooling and dilution of flame gases) actions. All of the proposed alternative agents are known to be less effective (i.e., considerably higher molar concentrations of the agent are required) than halon 1301. This reduction in effectiveness is attributed to the absence of bromine atoms in these chemicals and thus the absence of a highly effective chemical means of fire extinguishment.