Effect of CF3H and CF3Br on Laminar Diffusion Flames in Normal and Microgravity.
Effect of CF3H and CF3Br on Laminar Diffusion Flames in
Normal and Microgravity.
VanDerWege, B. A.; Bush, M. T.; Hochgreb, S.; Linteris,
Combustion Institute/Eastern States Section. Chemical
and Physical Processes in Combustion. Proceedings.
Fall Technical Meeting, 1995. October 16-18, 1995,
Worcester, MA, 443-446 pp, 1995.
Sponsor:National Aeronautics and Space Administration, Lewis
Research Center, Cleveland, OH
combustion; laminar flames; diffusion flames; gravity;
bromotrifluoromethane; experiments; microgravity
Due to the ban on production of bromotrifluoromethane
(CF3Br) because of its high ozone destruction potential,
there has been recent interest in finding a replacement
for it for fire extinguishing applications. While a
variety of potential replacements are being considered,
halogenated hydrocarbons may be a viable alternative for
some applications. Consequently, an improved
understanding of their action in flames will aid in
their effective use. In addition, CF3Br is used as a
fire suppressant on the space shuttle, and its action in
microgravity has not been tested in diffusion flames.
The present study investigates the effects of CF3Br and
trifluoromethane (CF3H), the simplest compound
representative of the fluorocarbons, in laminar
diffusion flames. The primary experiments are laminar
gas-jet diffusion flames burning in a quiescent
environment containing the inhibitor in normal and
microgravity. Experiments were conducted with CF3Br mole
fractions in the oxidizer gas of 0.5% to 3%, CF3H mole
fractions of 4% to 12%, oxygen mole fractions from 18%
to 30%, and ambient pressures of 101 kPa and 25 kPa.
Additional opposed-jet counterflow diffusion flame
experiments were used to investigate flame structures
observed in the microgravity flames.