When using the Flamelet model, no initialization data for the library species is required because no transport equations are solved for them. You can set values for the mixture fraction mean and variance, but Automatic is fine if you do not know of sensible initial values (a value of zero corresponds to 100% oxidizer, and a value of 1 corresponds to 100% fuel).

If you are modeling the formation of NO, you will need to set an initialization option for the NO component. For details, see NO Model.