code_saturne User's Forum

Hello,
I'm using "Code_Saturne version 8.0.2-patch-0062aaaf8".

The question concerns the gas combustion module, an infinitely rapid chemical diffusion flame.
In my case, I have one gas inlet and two Oxydant inlets.
The two Oxydant inlets have different temperatures: inlet_air_1 = 400 K and inlet_air_2 = 600 K.
In the GUI, it's not possible to define two different temperatures.

I tried:

- defining a volume zone in the inlet_air_1 pipe and applying a thermal source term to this zone. The thermal source is enthalpy (temperature not available). The calculation can be run. By viewing the results in Paravis, I can see the enthalpy production, but the air temperature in the pipe doesn't increase. The enthalpy source term does not affect the flow temperature.
I tried the same approach with the standard Eulerian single-phase module, and it works (enthalpy and temperature are linked).

- Modified the setup.xml file without success.

Questions:
- Is it possible to define two different temperatures for the Oxydant ?
- If so, how? (Perhaps it's possible in the cs_user_boundary_conditions-gas_3ptchem.f90 file?, but my first attemps are unsuccessful )

Thanks!

Hello,

Looking at the code, it seems that it is only possible to define multiple temperatures for premixed flames (Libby-Williams and EBU). For 3-point chemistry, the hinfue value is global to the model (which seems to be an unnecessary limitation, probably due to the initial coding rather that a real reason, bu I need to check with the combustion specialists).

For that model, temperature should be computed from enthalpy, so it is surprising that it does not increase also, though It may be useful to check the code for this.

Best regards,

Yvan

Hello,

Thank you Yvan. I am interested by the answer of the combustion specialistes.

In attached file the case with thermal source. It is possible that I did a mistake with the use of thermal source and enthalpy ...
The model is only for testing. The real case have very more complexe 3D.

Thanks !

Hello,
Does anyone have any ideas why the thermal source isn't working?
316 downloads. Someone has probably tried running the case...
Thanks very much.