HI Felix,
Sorry for the delayed response. I think the notification got lost in my outlook emails.
From your original post, i was of the impression that you were doing both FR and flamelet based modelling. But now from the last post, it is clear that you have using only FR approach and the difference between geom is mainly in the presence of bluff body. For the reaction to happen, Fuel and oxidizer need to be mixed within the flammability limit: this would have been achieved in the recirculation region close to bluff body and hence the system ignited with the hot temp trigger. You could compute the equivalence ratio using fuel and oxidizer mass fraction for the design w/o bluff body and the best guess is- the system isnt properly mixed there.
Based on your post in another Forum thread - i have a confusion in your original statement: why do you state that air-methane doesnt ignite while methane-air system ignites ? arent they the same.
You are navigating away from the AIS Discovery experience