error in coupling code_saturne and code_aster using Yacs

[lzhang]

Hello,

Yes, my program can run until the end, however the results are probably wrong.

I am trying to simulate the impact of fluid over a beam, and I did firstly the code chaining : I ran a code_saturne simulation with only the fluid and save the fluid force to a MED file, then I ran a code_aster simulation using PROJ_CHAMP to get the fluid force from the MED file. The results are quite satisfactory, with the beam oscillating due to the vortex shedding.

However when I did the coupling with Yacs, the beam did not move anymore (with a displacement of 1e-16). So I wonder there are some errors when transferring data from code_saturne to code_aster. You mentioned that there were bugs in code_aster, could you please give some details?

Thanks!

Regards,
Lei

[Yvan Fournier]

Hello,

The bugs are in the coupling routines, and probably related to a multiplying/scaling factor.

I don't know more, but the latest release of Salome_Meca (2017) contains the fixed version.

Regards,

Yvan

[lzhang]

Hello,

I checked the output information and I found that the face force sent by code_saturne is 0. This is very strange, as obviously I have fluid flow in the domain. Maybe there are some configuration errors in my code_saturne set up.

Could you please explain the meaning of fix force components in external coupling? For example when I choose F_x, this means that F_x will be sent to code_aster or the opposite?

Thanks,

Lei

[Yvan Fournier]

Hello,

No, this means the displacement in this direction is fixed to 0.

Regards,

Yvan

[lzhang]

Hello,

Thanks for your response! If I understand well, choosing F_z in fix force component has the same effect of setting asddlf(3, 1) = 0, where 3 means the Z direction and 1 means the first defined external structure?

So the value of asddlf should be either 1 or 1? Because in my simulation result, I have a very strange value of this variable: asddlf(:, 1) : 0 1072693248 0. I think the reason could be that this variable is not initialised. I am not sure if it's a bug in the code or some errors in my simulation configuration.

Best regards,
Lei

[Yvan Fournier]

Hello,

Which version od Salome_Meca (and Code_Saturne) are you using ?.

And sorry, checking the code, it seems you need to set "1" to free the movement in a given direction, and "0" to block it.

Initialization seems to be done normally in the code (all set to 1 by default if not using the GUI). Hoping it is not overwritten somewhere (which would be a bug).

Did you run with a debug build of Code_Saturne ? This includes additional checks.

Regards,

Yvan

[lzhang]

Hello,

I am using salome_meca2015_2 and code_saturne 5.0.4.

Indeed I used Gui to build my test case, and I have no idea where the variable asddlf is rewritten.

I would like also to check the face force, as it seems to be very small. Do you you know where the associated file is located?

And what do you mean by the debug build, is it in the installation phase? I am not familiar with that.

Thanks a lot!

Best regards,
Lei

[Yvan Fournier]

Hello,

As I wrote in a previous post, you need to upgrade to a recent version of code_aster so as to include bug fixes for FSI coupling. Fixes were included October 2016, so any version older than that should be avoided (unless you are ready to search in the commit history to retrieve patches and patch an older version).

Debug builds for Code_Saturne are a build option, detailed in the installation manual. You might not need using a debug build, but is is always recommended to have both debug and production builds.

Regards,

Yvan

[lzhang]

Hello,

As you recommended, I began to build my test case using salome_meca2017. However I encountered several problems:
firstly, when I launch the application runcase, I have following errors:
/home/lzhang/Study_Code_Saturne/Cas/test2017_cylindres_concentriques/RESU_COUPLING/20171211-1525/appli/runSession: Aucun fichier ou dossier de ce type
/home/lzhang/Study_Code_Saturne/Cas/test2017_cylindres_concentriques/RESU_COUPLING/20171211-1525/run_solver: ligne 14: /home/lzhang/Study_Code_Saturne/Cas/test2017_cylindres_concentriques/RESU_COUPLING/20171211-1525/appli/runAppli: Aucun fichier ou dossier de ce type

Then I made some symbolic links to build the missing files. I have now another error that I cannot solve:
th. 140564178081664 - Trace /home/A21173/smeca/yamm_build/V2017_0_2_build/V2017_public/modules/src/KERNEL/src/NamingService/SALOME_NamingService.cxx [1446] : CORBA::SystemException: unable to contact the naming service
Elapsed time before load: 207 ms
The imported file has errors
LogRecord: parser:FATAL:Unknown OutStreamPort Type: CALCIUM_double for node: inter_service port name: DTCALC (fsi_yacs_scheme.xml:46)


I hope that you could help!

Best regards,
Lei

[Yvan Fournier]

Hello,

Did you update the code_saturne.cfg file ? I have not checked with Salome_Meca 2017 yet, so I'll try a test case on my side and keep you informed within a few days.

Best regards,

Yvan