Running a combustion simulation in the CFX-Solver is similar to multicomponent fluid runs with the extensions explained in the following.
This applies also to non-reacting multicomponent flow. For multicomponent
fluids with heat transfer, the diffusion term assembly modes are reported for
the molecular and the turbulent diffusion, respectively. The option for each
part may be either generic assembly or unity Lewis number assumption,
+--------------------------------------------------------------------+
| Multi-Component Specific Enthalpy Diffusion |
+--------------------------------------------------------------------+
Enthalpy equation assembly for secondary terms derived from multi-
component species transport. Molecular and turbulent transport may
use either Unity Lewis Number (Le=1) assumption or generic assembly.
Domain Name : Default Domain
Mixture (Le_mol=gen, Le_trb=1 )
For single step reactions the heat release per chemical amount of reaction is reported. Numbers are in solver units. Positive numbers indicate exothermic reactions (heat is released) and negative numbers indicate endothermic reactions (energy required for the reaction to occur). The total heat release in the domain resulting from a particular reaction can be computed by multiplying the reactions heat release by its molar reaction rate and integrating over the domain.
+--------------------------------------------------------------------+
| Single Step Reactions Heat Release |
+--------------------------------------------------------------------+
Enthalpy per [mol] of reaction at reference conditions
(Pressure= 1.01325E+05, Temperature= 2.98150E+02)
HCO Oxygen = 5.5799E+05
HCN NO Destruction PDF = 1.8194E+05
HCN NO Formation PDF = 1.3458E+03
Reburn NO Fuel Gas PDF = 2.7885E+05
Prompt NO Fuel Gas PDF = -9.0298E+04
Thermal NO PDF = -1.8060E+05
Fuel Gas Oxygen = 5.1127E+05
The stoichiometric mixture fraction is reported when a
Flamelet model or Burning Velocity
model is used. If the stoichiometric mixture fraction is not specified in the
definition of the Flamelet library reaction object, the
stoichiometric value is reported as <unknown>.
+--------------------------------------------------------------------+
| Stoichiometric Mixture Fraction |
+--------------------------------------------------------------------+
Stoichiometric mixture fraction (Zst) for fluids with mixture
fraction combustion models.
Domain Name : run
Mixture Zst = 5.5000E-02
For the hydrocarbon fuel model (the Hydrocarbon Fuel
option for the Material setting) the results of the
proximate/ultimate analysis calculation are reported:
The initial composition of the particles (component mass fractions). These values will be applied when no user-specified initial particle composition is specified (default).
Molar mass and reference specific enthalpy for the
Volatilesmaterial that is released to the gas phase. The values reported here by default overrule the data specified in the corresponding material object.For single step reactions the relative stoichiometric coefficients, which are derived from the fuel analysis, are reported. These values are applied when the
Fuel Analysisoption is specified in the reaction for the corresponding reactant or product.For multiphase reactions the relative mass coefficients, which are derived from the fuel analysis, are reported. These values are applied when the
Fuel Analysisoption is specified in the reaction for the corresponding reactant or product.====================================================================== HC Fuel Proximate/Ultimate Analysis ====================================================================== Initial mass fractions for particle : HC Fuel Ash = 1.2580E-01 Char = 0.0000E+00 Raw Combustible = 8.7420E-01 Volatiles material properties : Fuel Gas Molar Mass [kg/kmol] = 18.234 Ref. Spec. Enthalpy (p= 1.01325E+05, T= 2.98150E+02) = -7.1827E+06 +--------------------------------------------------------------------+ | Autocomputed Stoichiometric Coefficients | +--------------------------------------------------------------------+ Reaction (volatiles oxidation) : Fuel Gas Oxygen Reactants: Fuel Gas = 1.0000E+00 O2 = 1.3558E+00 Products: CO2 = 9.3953E-01 H2O = 1.1267E+00 Reaction (NO reburn) : Reburn NO Fuel Gas PDF Reactants: Fuel Gas = 3.6879E-01 NO = 1.0000E+00 Products: CO2 = 3.4648E-01 H2O = 4.1552E-01 N2 = 5.0000E-01 +--------------------------------------------------------------------+ | Autocomputed Mass Coefficients | +--------------------------------------------------------------------+ Reaction (devolatilisation) : HC Fuel Devolat HCN Reactants: HC Fuel.Raw Combustible = 1.0000E+00 Products: Gas Mixture HCN NO.Fuel Gas = 5.0003E-01 Gas Mixture HCN NO.HCN = 1.1857E-02 HC Fuel.Char = 4.8812E-01 Reaction (char oxidation) : HC Fuel Char Gibb HCN Reactants: Gas Mixture HCN NO.O2 = 2.6049E+00 HC Fuel.Char = 1.0000E+00 Products: Gas Mixture HCN NO.CO2 = 3.5817E+00 Gas Mixture HCN NO.HCN = 2.3164E-02