Computation of Nonpremixed Methane-Air Diffusion Flames in Microgravity

무중력에서의 비예혼합 메탄-공기 확산화염의 전산

  • Park, Woe-Chul (Department of Safety Engineering, Pukyong National University)
  • 박외철 (부경대학교 안전공학과)
  • Published : 2004.03.01

Abstract

The structure of the nonpremixed methane-air counterflow flames in microgravity was investigated by axisymmetric simulation with Fire Dynamics Simulator (FDS) to evaluate the numerical method and to see the effects of strain rate and fuel concentration on the diffusion flame structure in microgravity. Results of FDS for the methane mole fractions, $X_m$=20, 50, and 80% in the fuel stream, and the global strain rates $a_g$=20, 50, and $90s^{-1}$ for each methane mole fraction were compared with those of OPPDIF, an one-dimensional flamelet code. There was good agreement in the temperature and axial velocity profiles between the axisymmetric and one-dimensional computations. It was shown that FDS is applicable to the counterflow flames in a wide range of strain rate and fuel concentration by predicting accurately the flame thickness, flame positions and stagnation points.

Keywords

methane-air nonpremixed counterflow flame;microgravity;global strain rate;fuel concentration;temperature;axial velocity

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