code_saturne User's Forum

Yvan, thank you for the insight and the suggestions.

I've tried several options and CFL-Number choices. As the velocity magnitude in the current setup covers a large span, the CFL-Numbers are either much to large resulting in unphysical solutions or way to small and the checkerboarding occurs ...

Dear Yvan,

thank you for the suggestion.

The CFL-Numbers seem to be in a valid range, There are a bit large in the tetrahedral region but shouldn't cause the checkerboard pattern.
Velocity-Z.png CFl.png

I've attached the XML-file and the logs. CS-Version 6.0.4

Thank you in advance.
Kind ...

Hello,

in a very early stage of my CFD I could observe solution artefacts in the z-component of the velocity (the stripes in the solution), Bulk velocity (x-direction) is approx. 30m/s.
Vel-Artefacts.PNG

With ongoing solution process the solution worses and a pronounced pattern in the velocity ...

Hello,

applying cs_mesh_refine_simple() on meshes with periodic boundaries throws a sigsegfault during the refinement process (CS 6.0.4). Probably it can’t handle the ghost cells, since the refinement on the same mesh without periodic boundaries works well.
Do you have a recommendation for using ...

Hello,

I need to do some gradient caluculations in cs_user_postprocess.
Is it okay to fill the value array from which I calculate the gradient up to n_cells? Or do I have to take care on the ghost cells and should fill the array with n_cells_with_ghosts values?

A skeleton of my routine:

cs ...

Version 5.0.9

Kind regards,
Ralf

Thank you ,

seems to a problem of the code_saturne Version.
Comparing the parameter files I see no difference. Running your setup with my older 5.xx version i get the same false results using a 6.04 version i get the expected output.
thank you.

Kind regards
Ralf

Hello Yvan,

sorry for my late reply, I was in holiday.
Maybe I didn't get it. What I want is that in the upper channel the pressure is lower than in the lower channel and the pressure difference is about 10% (setup in Test.zip).
What I get is, independant of the variable "pressure" or "total ...

Dear Yvan,

I have attached my simplified Test-Case.

Kind regards,
Ralf

Thank you, Yvan.

Following your suggestion I have changed BC_4 to an Imposed-P-Outlet, setting the Pressure to p = 1e5 and BC_2 to an imposed P-Outlet with p=1.1e5. This should force a pressure difference in the range of 10%.

Have look at the result Code_Saturne_Forum_3.png
Still not the expected ...