[kandelabr]

I'm looking at radiationProperties file in this tutorial: /opt/OpenFOAM/OpenFOAM-v1906/tutorials/heatTransfer/buoyantSimpleFoam/hotRadiationRoomFvDOM

and I am not sure what these values mean:

absorptionEmissionModel constantAbsorptionEmission;

constantAbsorptionEmissionCoeffs
{
   absorptivity    absorptivity    [ m^-1 ]         0.5;
   emissivity      emissivity      [ m^-1 ]         0.5;
   E               E               [ kg m^-1 s^-3 ] 0;
}

If there's air in the room, isn't it a non-participating medium so these values should be 0 or at least close to 0? What would this mean in practice?