Convergence in CFX5.7

July 20, 2004, 20:26

Dear all

I'm currently running a draft tube problem with 3 outlets. CFX5.7 always complains about backflows into the domain when I specified outlet BCs. I then discarded and rather specified OPENINGS which actually represent the original problem. CFX didn't complain about walls anymore but instead there is a problem with convergence. It just oscillated around 10e-2 as max Residual but the target was 10e-5. I did reduce the timesteps and try all probable causes of this problem but none of them seems to slove the problem. Has anybody encountered such a problem? Any advice or tips on this is highly welcome.

Thanks a lot for responding to this!!

cheers

July 26, 2004, 22:52

Hi KKA,

Try using outlets, and moving them further away from the region of interest.

Glenn

July 20, 2004, 20:26	Convergence in CFX5.7	#1
KKA Guest Posts: n/a	Dear all I'm currently running a draft tube problem with 3 outlets. CFX5.7 always complains about backflows into the domain when I specified outlet BCs. I then discarded and rather specified OPENINGS which actually represent the original problem. CFX didn't complain about walls anymore but instead there is a problem with convergence. It just oscillated around 10e-2 as max Residual but the target was 10e-5. I did reduce the timesteps and try all probable causes of this problem but none of them seems to slove the problem. Has anybody encountered such a problem? Any advice or tips on this is highly welcome. Thanks a lot for responding to this!! cheers

July 26, 2004, 22:52	Re: Convergence in CFX5.7	#2
Glenn Horrocks Guest Posts: n/a	Hi KKA, Try using outlets, and moving them further away from the region of interest. Glenn

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