code_saturne User's Forum

Not an expert on k-epsilon, however, aren't all model coefficients defined in cs_turbulence_model.c/cpp? They may be shared across several models perhaps?
https://github.com/code-saturne/code_sa ... _model.cpp

Best regards,
Sean Hanrahan

Hi Yvon,

Just continuing this conversation, would it be a lot of work to implement this second-order timestep into the k-w model? Or would it simply be modifying a 10-20 lines of code to also account for the k-w SST model in this scheme?

Any guidance with this would be greatly appreciated ...

Hi Maxime,

When you say theoretical y+ value, how are you calculating your wall-shear stress?

As you know, the methodology of the velocity gradient calculation on the wall will make a difference to your wall-shear stress term, that is then used in your wall friction velocity ($\overline{u}_tau ...

Hi Maxime,

Perhaps to get started, perhaps you could consider a sliding wall boundary condition? I am sure that it isn't exactly waht you want, but you could examine the shear-stresses on the wall after the calculation, to verify whether you have the basics correctly accounted for.

Example: https ...

Hi Everybody,

I would just like to confirm how people are undertaking their channel flow calculations in Code Saturne.
I have successfully undertaken a channel flow calculation with the inlet/outlet mapping condition in the GUI. The results look good, but I could only get the case running well with ...

Hi Yvon,

So the code seems to hang after "Destroying structures and ending computation" in the run_solver.log files.

The problem is that the code keeps running in PBS, so I am being billed, even through the code is no longer running.

Local case configuration:

Date: Mon Apr 7 15:52:37 2025 ...

Hi Daniele,

Could you please post (or PM) a few screen shots of your problem? It would be good to see the components of the Reynolds-stress tensor, epsilon, alpha, MPI partitioning, and the velocity components as well. :) Could you please also show me your run_solver.log summary of the residuals ...

Dear Yvon,

I just wanted to verify something that I have observed on my version of CS8.3 on an Intel system, after updating my code to commit 7342705 (Main branch of git.).

The solver seems to be hanging on the last timestep, and I wanted to see whether you observed this on your system as well?
I ...

Hi Daniele,

The conclusion that I came to was that there was an MPI issue in CS8.2 relating to the Rij tensor, as the number of clipped cells was increasing with core count. When I visualised this, the clipping seemed to be related to the regions of the interface between MPI blocks. As I increased ...

Hi Yvon,

In addition to my last post, I wanted to verify whether second-order timestepping has ever been available for the k-omega SST model in CS. The reason I ask, is that in Application of recently developed elliptic blending based models to separated flows by Billard, Revell, and Craft, the ...