syrthes coupling on restart point

[jgd23]

Hello,

I try to use a restart point with syrthes coupling for having stationnary temperature fields. Only with CS I have realistic results with a frozen velocity field and compute the temperature in fluid with large time steps.
If I try to do the same calculation including syrthes coupling I have no more realistic temperature fields. It seems that the frozen velocity field is not taken in account in the temperature distribution (it seems the fluid is not moving like a solid phase). however I can visualize the frozen velocity in the fluid domain.

The coupling case is running fine without restart for small time steps.

Any suggestions about this problem?

Best regards

Julien

[Yvan Fournier]

Hello,

This is strange. Did you test restarts without a froze field ? Did you configure the restart on the Syrthes side ?

Regards,

Yvan

[jgd23]

Hello,

Yes the restart file is also done for syrthes. Maybe my time step size is too large with the restart calculation. I have 0.01 sec for a Courant number less to 50 with Naviers Stockes and I change for 5 sec for the temperature calculation with velicity and pressure frozen fields. Is there a rule to limit the time step size in such case?

Best regards

Julien

[Yvan Fournier]

Hello,

No, there is no specific recommendation. A restart should "just work". I have not tested restarts with Syrthes coupling in a specific manner recently, but users who run major studies should use it regularly (as most computation queues are limited to 2 or 3 days, and long unsteady computations on large meshes require more than that), and have not reported issues.

If you have a small test case you can post, I'll try to run it.

Best regards,

Yvan

[jgd23]

Hello,

I post my case but I can not add the restart point because it's larger than 10MB even compressed.
I have done 200 iterations of 0.01 sec to have the restart point and continue until this point for several hundreds iterations of 0.5 sec (you can see my files), I have the same problem than for larger time steps of 5 sec.

Thank you for your help.

Best regards

Julien

[jgd23]

Hello,

I redo the the case in exploiting symetry axis to reduce the size of the files. The restart file is now included in the joined file.

Best regards

Julien

[jgd23]

Hello,

Have you some time to remake the restart case?

Thank you for your help

Best regards

Julien

[Yvan Fournier]

Hello,

Not yet, and I won't be able to test it before next week.

Regards,

Yvan

[jgd23]

Hello Yvan,

Have you some time to take a look to my restart problem?

Thank you

Best regards

Julien

[Yvan Fournier]

Hello,

Sorry, no, I have not found the time to check this yet. I'm keeping it not too far from the top of my TODO list.

Regards,

Yvan