Oxygen Volume Fraction

[SaharRasoulpour]

I have a question regarding oxygen concentration. For the pyrolysis of pine, in the reaction rate, if N_O2 is not equal to zero, how can we define the oxygen volume fraction X_O2 in the MATL ID? Your response would be highly appreciated.

[drjfloyd]

The volume fraction comes from the gas phase calculation.

[SaharRasoulpour]

It means that the mole fraction of oxygen does not need to be explicitly defined? When NU_SPEC = -0.1 is set for oxygen in the MATL ID for pyrolysis, what does it mean?

[drjfloyd]

What does the User's Guide say NU_SPEC means?

[SaharRasoulpour]

NU_SPEC specifies the amount of a gas species that is produced or consumed per unit mass of the reacting solid material.
My question is about X_O2 as a volume fraction. You mentioned that it comes from the gas-phase calculation. How can it be defined in the input file?

[drjfloyd]

Please read the User's Guide.