Computation of Nonpremixed Methane-Air Flames in Microgravity II. Radius and Thickness of Flame

무중력에서의 비예혼합 메탄-공기 화염의 전산 II. 화염의 반경과 두께

  • Published : 2004.09.01

Abstract

To evaluate the numerical method in simulation of diffusion flames and to see the effects of strain rate and fuel concentration on the flame radius and thickness, the nonpremixed methane-air counterflow flames in microgravity were simulated axisymmetrically by using the MST Fire Dynamics Simulator (FDS). The $1000^{\circ}C$ based flame radius and thickness were investigated for the mole fraction of methane in the fuel stream, $X_m=20,\;50,\;and\;80\%$ and the global strain rates $a_g=20,\;60,\;and\;90s^{-1}$ for each mole fraction. The flame radius increased with the global strain rate while the flame thickness decreased linearly as the global strain rate increased. The flame radius decreased as the mole fraction increased, but it was not so sensitive to the mole fraction compared with the global strain rate. Since there was good agreement in the nondimensional flame thickness obtained with OPPDIF and FDS respectively, it was confirmed that FDS is capable of predicting well the counterflow flames in a wide range of strain rate and fuel concentration.

Keywords

counterflow flame;microgravity;global strain rate;fuel concentration;flame thickness;flame radius

References

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