Flame front geometry in premixed turbulent flames

Conference · Sun Dec 01 04:00:00 EST 1991

OSTI ID:10134366

Shepherd, I G ^[1]; Ashurst, W T ^[2]

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1. Lawrence Berkeley Lab., CA (United States)
2. Sandia National Labs., Livermore, CA (United States)

Experimental and numerical determinations of flame front curvature and orientation in premixed turbulent flames are presented. The experimental data is obtained from planar, cross sectional images of stagnation point flames at high Damkoehler number. A direct numerical simulation of a constant energy flow is combined with a zero-thickness, constant density flame model to provide the numerical results. The computational domain is a 32{sup 3} cube with periodic boundary conditions. The two-dimensional curvature distributions of the experiments and numerical simulations compare well at similar q{prime}/S{sub L} values with means close to zero and marked negative skewness. At higher turbulence levels the simulations show that the distributions become symmetric about zero. These features are also found in the three dimensional distributions of curvature. The simulations support assumptions which make it possible to determine the mean direction cosines from the experimental data. This leads to a reduction of 12% in the estimated flame surface area density in the middle of the flame brush. 18 refs.

• Research Organization: Lawrence Berkeley Lab., CA (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC03-76SF00098; AC04-76DR00789
• OSTI ID: 10134366
• Report Number(s): LBL--31590; CONF-920707--26; SAND--92-8504C; ON: DE92010310
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400800
COMBUSTION, PYROLYSIS, AND HIGH-TEMPERATURE CHEMISTRY
ETHYLENE
FLAME PROPAGATION
FLAMES
METHANE
NUMERICAL SOLUTION
TURBULENCE