Computation of a Low Strain Rate Counterflow Flame in Normal and Zero Gravity

정상중력 및 무중력에서의 저변형율 대향류화염의 전산

  • Woe-Chul Park (Department of Safety Engineering, Pukyong National University)
  • Published : 2002.09.01

Abstract

A near extinction nonpremixed counterflow flame of 19% methane diluted by 81% nitrogen by volume and undiluted air at a low global strain rate, 20 s-1, was computed. Investigations were focused on effects of the duct thickness and velocity boundary conditions on the flame structure in normal and zero gravity conditions. The results showed that, under normal gravity conditions, the effects of the duct thickness and velocity boundary conditions were significant by shifting the flame position, but negligible in zero gravity. The differences in flame structure were caused by buoyancy, and hence should be considered in the measurements in normal gravity.

Keywords

numerical simulations;air-methane counterflow flame;duct thickness;velocity boundary conditions;flame structure;zerogravity

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