The Role of Large Scale Mixing and Radiation in the Scaling of NOx Emissions From Unconfined Flames

  • Newbold, Greg J.R. (Department of Mechanical Engineering Adelaide University) ;
  • Nathan, Graham J. (Department of Mechanical Engineering Adelaide University) ;
  • Nobes, David S. (Department of Mechanical Engineering Adelaide University) ;
  • Turns, Stephen R. (Department of Mechanical and Nuclear Engineering The Pennsylvania State University)
  • Published : 2002.03.31

Abstract

Measurements of global emissions, flame radiation and flame dimensions are presented for unconfined turbulent-jet and precessing-jet diffusion flames. Precessing jet flames are characterised by increases in global flame radiation and global flame residence time for methane and propane fuels, however a strong dependency of the NOx emission indices on the fuel type exists. The fuel type dependence is considered to be because soot radiation is more effective than gas-radiation at reducing global flame temperatures relative to adiabatic flame temperatures and reducing the NO production rate.

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