code_saturne User's Forum

Hello,

I am using the 4.0 GUI version of code saturne.

I was wondering how can I change the model coefficients (eg. sigma and C ..etc). This is not available in the GUI. Same for K omega model, what is available is only K omega SST, but I would like to use K-omega standard , how (or more precisely where ) can i modify the code?


in the file cs_user_parameters.f90 it is stated:


! User subroutines for input of calculation parameters (Fortran modules).
! These subroutines are called in all cases.

! If the Code_Saturne GUI is used, this file is not required (but may be
! used to override parameters entered through the GUI, and to set
! parameters not accessible through the GUI).

! Several routines are present in the file, each destined to defined
! specific parameters.

! To modify the default value of parameters which do not appear in the
! examples provided, code should be placed as follows:
! - usipsu for numerical and physical options
! - usipes for input-output related options

! If we are using the Code_Saturne GUI:

! parameters protected by a test of the form:

! if (ixmlpu.eq.0) then
! ...
! endif

! should already have been defined using the GUI, so only
! experts should consider removing the test and adapting them here.

!===============================================================================

! --- Turbulence
! 0: Laminar
! 10: Mixing length
! 20: k-epsilon
! 21: k-epsilon (linear production)
! 30: Rij-epsilon, (standard LRR)
! 31: Rij-epsilon (SSG)
! 32: Rij-epsilon (EBRSM)
! 40: LES (Smagorinsky)
! 41: LES (Dynamic)
! 42: LES (WALE)
! 50: v2f (phi-model)
! 51: v2f (BL-v2/k)
! 60: k-omega SST
! 70: Spalart Allmaras
! For 10, contact the development team before use

if (ixmlpu.eq.0) then

iturb = 21

endif


doesn't provide adjustable parameters, I am not sure if this is the right place to search for this.

Thanks,

Hello,

The model coefficients are not in the GUI, as they are considered "advanced".

They are initialized in iniini.f90 (a non-user subroutine), and you can change them in cs_user_parameters.f90/usipsu.

The matching variables are documented in the Doxygen documentation, and possibly in the user pdf guide.

In any case, Code_Saturne includes several k-epsilon variants (standard and linear-production), but only the SST variant of k-omega. I am not knowledgeble about the standard k-omega variant, so I don't know if you just need to change constants or would need a different model...

Regards,

Yvan