Trioxane-Air Counterflow Diffusion Flames in Normal and Microgravity.
Trioxane-Air Counterflow Diffusion Flames in Normal and
Linteris, G. T.; Rumminger, M. D.; Urban, D. L.
Microgravity Combustion Workshop, Sixth (6th)
International. Proceedings. NASA/CP-2001-210826. May
22-24, 2001, Cleveland, OH, 385-388 pp, 2001.
microgravity; flame spread; flammability; fire
Trioxane, a weakly bound polymer of formaldehyde
(C3H6O3, melting point 61 deg C, boiling point 115 deg
C), is a uniquely suited compound for studying material
flammability. Like many of the more commonly used
materials for such tests (e.g. delrin, polyethylene,
acrylic sheet, wood, and paper), it displays relevant
phenomena (internal heat conduction, melting,
vaporization, thermal decomposition, and gas phase
reaction of the decomposition products). Unlike the
other materials, however, it is non-sooting and has
simple and well-known chemical kinetic pathways for its
combustion. Hence it should prove to be much more useful
for numerical modeling of surface combustion than the
complex fuels typically used. We have performed the
first exploratory tests of trioxane combustion in the
counterflow configuration to determine its potential as
a surrogate solid fuel which allows detailed modeling.
The experiments were performed in the spring and summer
of 1998 at the National Institute of Standards and
Technology in Gaithersburg, MD, and at NASA-GRC in
Cleveland. Using counterflow flames at 1-g, we measured
the fuel consumption rate and the extinction conditions
with added N2 in the air; at mg conditions, we observed
the ignition characteristics and flame shape from video
images. We have performed numerical calculations of the
flame structure, but these are not described here due to
space limitations. This paper summarizes some burning
characteristics of trioxane relevant to its use for
studying flame spread and fire suppression.