We’re putting the final touches on our new badges platform. Badge issuance remains temporarily paused, but all completions are being recorded and will be fulfilled once the platform is live. Thank you for your patience.

Ansys Learning Forum › Forums › Discuss Simulation › Fluids › Residuals oscilalting using the species transport model › Reply To: Residuals oscilalting using the species transport model

July 17, 2023 at 9:49 pm
Noelly
Subscriber

Hello,

 

Thanks for your answers and apologies for the late reply, I am really not familiar with the physics of combustion and wanted to review a few things before asking for some more help.

So


My mole fractions from before are wrong but I was wondering where the 21% came from. So for air it would be 1/(1+3.76) = 0.21

But shouldn’t the mole fraction for the case where I have CH4 as well be calculated as

2/( 1 + 2 + 2*3.76) = 0.19 for O2

1/( 1 + 2 + 2*3.76) = 0.095 for CH4

?

 

I fixed the turbulent intensity using this formula


It is now about 14 %

 

Regarding the flame, I asked on the learning hub before which model I should be using and they said that since my actual system does not have a flame, I could model it with the species transport model.