Simulation of Cup-Burner Flames in Microgravity.
Simulation of Cup-Burner Flames in Microgravity.
(1146 K)
Katta, V. R.; Takahashi, F.; Linteris, G. T.
Combustion Institute/Central States Section. Third
(3rd) Joint Meeting of the U.S. Sections. Session A4:
Combustion I. Hosted by The Central States Section of
the Combustion Institute and the University of Illinois
at Chicago. March 16-19, 2003, Chicago, IL, A18/1-6 pp,
2003.
Keywords:
microgravity; simulations; carbon dioxide; cup Burner;
fire suppression; flame extinction; flame stabilization
Abstract:
The extinction process of cup-burner flames under
normal-gravity conditions were previously studied. As
the low-speed diffusion flames behave differently in
microgravity compared to those on earth, it is important
to understand the structure of cup-burner flame and its
extinction characteristics under 0g conditions. A
numerical study was performed in the present paper using
a time-dependent, axisymmetric model and by
incorporating detailed chemical kinetics of CH4 and O2.
Calculations were performed for the cup-burner flame
under different gravitational forces. It was observed
that the cup-burner flame ceases to flicker under
gravitational forces less than 0.5g. As the buoyancy
force was reduced, the flame diameter increased, the tip
of the flame opened, and the flame at the base became
vertical. Through numerical experiments it was found
that radiative heat loss was predominantly responsible
for the extinction of flame in the tip region under 0g
conditions. In contrast, 1g flames were not affected
much by the radiative heat loss.
