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Old   September 8, 2020, 18:27
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Y27
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Yunus Aysan
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Dear Esteemed Members,

Thank you for taking the time to read my post!

Can anyone shed some light on what may be causing the warning message in the attached image?

AMG Warning Message.jpg

It started at around the 1000th iteration, and continued until I stopped the simulation at the 5000th iteration.

As far as I am aware I am already using double precision which is the 64-bit version of STAR, or so I have read online. I've attached a screen shot of the task manager which shows I am running the 64-bit version. Is there a possibility that STAR is in fact running in mixed-precision mode even though the task manager shows 64-bit?

64bit.JPG

Could this be related to bad cell quality in the mesh?

Can I ignore this warning as the results I have attained appear to be reasonable?

Any advice and/or guidance is much appreciated, thank you!
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Old   September 9, 2020, 08:06
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Matt
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Almost certainly the result of poor quality mesh. Are you using automatic surface repair in your mesh setup? If not, use it. If so, you may need to resort to manual surface repair or try the cell quality remediation option.
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Old   September 9, 2020, 17:55
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If i remember things right - might in particular be an issue with Interface between Regions.
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Old   September 22, 2020, 09:53
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Y27
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Hi, thanks for your replies.

I switched to laminar flow and models, and the warning message went away - or the simulation did not complete enough iterations for it to show up (The solution appeared to have converged).

Quote:
Are you using automatic surface repair in your mesh setup?
It does not give me the option as I am in 2D.

I would obviously like to keep the models as turbulent so I will try to play with the mesh manually.
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