Numerical prediction of NOx emissions in a full-scale furnace
Keywords:Oxides of nitrogen (NOx), Emission, Turbulent combustion, CFD simulation, Industrial furnace
AbstractThe present paper deals with a numerical predic-tion of the thermal level and emission rate of nitrogen ox-ides within an industrial furnace. Favre averaged forms of the governing equations accounting for radiative heat losses are solved via a finite volume formulation. Turbu-lent fluxes are closed using a model for which a limited Pope correction is performed. The relaxation model of Magnussen is used to describe the two-step chemis-try/turbulence interaction for the non-premixed flame. The effect of the swirl number has been also investigated. The predicted static temperature as well as NO emission rate at the furnace exit show good agreement with in-situ meas-urements. In addition, the numerical computation shows that the depression is about 28% for the rate of NO, which it is obtained by adopting a moderate swirl at the primary-air entrance.
MECHANICS OF FLUIDS AND GASES