Selection of a Simulant of CF3Br for Use in Engine Nacelle Certification Tests.
Selection of a Simulant of CF3Br for Use in Engine
Nacelle Certification Tests.
(1154 K)
Womeldorf, C. A.; Mitchell, M. D.; Grosshandler, W. L.
Halon Options Technical Working Conference.
Proceedings. HOTWC 1995. May 9-11, 1995, Albuquerque,
NM, 197-210 pp, 1995.
Sponsor:
Naval Air Warfare Center, Lakehurst, NY
Keywords:
aircraft certification; halon 1301; pentafluoroethane;
sulfur hexafluoride; halon simulants; nacelle fires;
fire suppression; aircraft engines; boiling point;
critical temperature; halon alternatives
Abstract:
This paper describes the selection of a simulant of
CF3Br for the purpose of certification testing engine
nacelles fire suppression systems. In order to
illustrate the storage, delivery, and distribution
requirements of CF3Br, relevant characteristics of
engine nacelle fire suppression systems and
certification tests are briefly summarized. An initial
screening of over 1300 chemicals based upon the boiling
point, critical temperature, and molecular weight of
CF3Br is described, and the nine potential candidate
simulants that were found are listed. Three final
candidates (SF6, C2HG5, and CHCIF2) were selected for
experimental testing based upon their vapor pressures,
Jakob numbers, and the requirements of this application:
ozone depletion potential, flammability, corrosiveness,
toxicity, stability, and atmospheric lifetime. To
evaluate the hydraulic properties of the simulants
compared to CF3Br, pressure traces of discharges through
a piping system are compared. A second comparison using
high speed movies of the spray plumes at the end of the
piping system is described. Results from these
comparisons of the three candidate simulants with CF3Br
are presented.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899