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TITLE   : COMBUSTION AND NOx MODELLING FOR 2-D TURBULENT FLAME
    BY      : Radian Corporation              - P Adnani
              CHAM Development Team           - M R Malin
    FOR     : Radian Corporation, Irvine, USA
    DATE    : 1994                          PHOENICS Version : 2.1
    
MODEL OBJECTIVES :
  - The main objective of the model is to predict the NOx formation when
      combustion products from gas-fired burners, operating at different
      stoichiometries, are mixed in a large utility boiler.
   
- The model may be used to help determine the optimum firing condition
      for each burner in a utility boiler.
FLOW DETAILS :
     The model is intended for inclusion in a 3D test-boiler BFC
     geometry, but was developed on a 2D pipe geometry with somewhat
     arbitrary operating conditions, as indicated below:
   - 2D steady turbulent diffusion flame in a pipe of 0.32m diameter
       and 2m length.
   
- Cylindrical-polar mesh with 40 radial and 20 axial cells.
   
- Coaxial fuel and oxidiser streams are admitted separately into the
       pipe and then they burn in a turbulent diffusion flame.
   
- The fuel jet enters through a pipe of 0.16m diameter and comprises
       2 fuels (CO and H2), N2, CO2 and H2O at a temperature of 1754 C.
   
- The oxidiser jet enters through an annulus and comprises O2, N2, CO2
       and H2O at a temperature of 1518 C.
   
- The oxygen supply is 66% above stoichiometric.
 MAIN FEATURES OF MODEL:
   Turbulence is represented via the k-e turbulence model.
   The main combustion process is modelled by the oxidation of CO and
       H2 by two infinitely fast, global irreversible reactions.
   The reactants participating in these reactions cannot exist at the
       same place at any time; and the composition is determined via the
       solution of the mixture fraction.
   The enthalpy-temperature relationship allows for variable specific
       heats and heats of reaction.
   Radiative heat transfer is modelled via the solution of the
       radiosity equation for a gray medium.
   NO emissions calculated from the Zeldovich mechanism coupled with
       a fuel kinetics mechanism consisting of 8 reactions.
    PICTURES :
VELOCITY VECTORS
    
O2 MASS-FRACTION CONTOURS
    
TEMPERATURE CONTOURS ( DEG K )
    
NO MASS-FRACTION CONTOURS
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