# Species definitions

Enabling the species mass fraction solver and specifying species model options.

| Description | Type | Default
--- | --- | --- | ---
species.solve | Specified name of the species or None to disable the species solver. The name assigned to the species solver is used to specify species inputs. | String | None

The following inputs must be preceded by the “species.” prefix

| Description | Type | Default
--- | --- | --- | ---
[specie0].molecular_weight | Value of species molecular weight. [required if fluid.molecular_weight=’mixture’]. | Real | 0
diffusivity | Specify which diffusivity model to use for species [required]. Available options include: ‘constant’ for constant diffusivity model | String | None
diffusivity.constant | Value of constant species diffusivity. [required if diffusivity_model=’constant’]. | Real | 0
specific_heat | Specify which specific heat model to use for species [required if fluid.molecular_weight=’mixture’]. Available options include: ‘constant’ for constant specific heat model ‘nasa7-poly’ for NASA7 Polynomials model | String | None
[specie0].specific_heat.constant | Value of constant species diffusivity. [required if diffusivity model=’constant’]. | Real | 0
[specie0].specific_heat.NASA7.a[i] | Value of i-th coefficient, with i=0,..,6 for NASA7 polynomial coefficient [required if specific heat model=’NASA7-Poly’]. | Real | 0
[specie0].enthalpy_of_formation | Value of constant enthalpy of formation. [required if specific heat model=’constant’]. | Real | 0

Below is an example for specifying species solver model options.

    species.solve = O2  CO  CO2  Fe2O3  FeO

    species.diffusivity = constant
    species.diffusivity.constant = 1.9e-5

    species.specific_heat = NASA7-poly

    # Oxygen
    species.O2.molecular_weight = 31.99880e-3
    species.O2.specific_heat.NASA7.a0 =  3.78245636E+00    3.66096065E+00
    species.O2.specific_heat.NASA7.a1 = -2.99673416E-03    6.56365811E-04
    species.O2.specific_heat.NASA7.a2 =  9.84730201E-06   -1.41149627E-07
    species.O2.specific_heat.NASA7.a3 = -9.68129509E-09    2.05797935E-11
    species.O2.specific_heat.NASA7.a4 =  3.24372837E-12   -1.29913436E-15
    species.O2.specific_heat.NASA7.a5 = -1.06394356E+03   -1.21597718E+03

    # Carbon monoxide
    species.CO.molecular_weight = 28.01040e-3
    species.CO.specific_heat.NASA7.a0 =  3.57953350E+00    3.04848590E+00
    species.CO.specific_heat.NASA7.a1 = -6.10353690E-04    1.35172810E-03
    species.CO.specific_heat.NASA7.a2 =  1.01681430E-06   -4.85794050E-07
    species.CO.specific_heat.NASA7.a3 =  9.07005860E-10    7.88536440E-11
    species.CO.specific_heat.NASA7.a4 = -9.04424490E-13   -4.69807460E-15
    species.CO.specific_heat.NASA7.a5 = -1.43440860E+04   -1.42661170E+04

    # Carbon dioxide
    species.CO2.molecular_weight = 44.00980e-3
    species.CO2.specific_heat.NASA7.a0 =  2.35681300E+00    4.63651110E+00
    species.CO2.specific_heat.NASA7.a1 =  8.98412990E-03    2.74145690E-03
    species.CO2.specific_heat.NASA7.a2 = -7.12206320E-06   -9.95897590E-07
    species.CO2.specific_heat.NASA7.a3 =  2.45730080E-09    1.60386660E-10
    species.CO2.specific_heat.NASA7.a4 = -1.42885480E-13   -9.16198570E-15
    species.CO2.specific_heat.NASA7.a5 = -4.83719710E+04   -4.90249040E+04

    # Hematite
    species.Fe2O3.molecular_weight = 159.68820e-3
    species.Fe2O3.specific_heat.NASA7.a0 =  1.52218166E-01    2.09445369E+01
    species.Fe2O3.specific_heat.NASA7.a1 =  6.70757040E-02    0.00000000E+00
    species.Fe2O3.specific_heat.NASA7.a2 = -1.12860954E-04    0.00000000E+00
    species.Fe2O3.specific_heat.NASA7.a3 =  9.93356662E-08    0.00000000E+00
    species.Fe2O3.specific_heat.NASA7.a4 = -3.27580975E-11    0.00000000E+00
    species.Fe2O3.specific_heat.NASA7.a5 = -1.01344092E+05   -1.07936580E+05

    # Wustite
    species.FeO.molecular_weight = 71.84440e-3
    species.FeO.specific_heat.NASA7.a0 =  3.68765953E+00    1.81588527E+00
    species.FeO.specific_heat.NASA7.a1 =  1.09133433E-02    1.70742829E-02
    species.FeO.specific_heat.NASA7.a2 = -1.61179493E-05   -2.39919190E-05
    species.FeO.specific_heat.NASA7.a3 =  1.06449256E-08    1.53690046E-08
    species.FeO.specific_heat.NASA7.a4 = -2.39514915E-12   -3.53442390E-12
    species.FeO.specific_heat.NASA7.a5 = -3.34867527E+04   -3.30239565E+04