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Linear solver fails only in the last iteration

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Old   January 16, 2014, 08:52
Default Linear solver fails only in the last iteration
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Govindaraju
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Dear all

I am simulating a pulsatile flow through curved pipe.
The duration of the cycle is 1s. I am running the simulation for 4 cycles. time step I assigned is 0.01s. So 100 iteration is required to complete a cycle. During this cycle the velocity increases to maximum and become zero.
in solver W momentum, v momentum shows "F' at 99 th iteration 199th, 299th and 399 iterations.( I use smooth transition inflation)

If I use first layer inflation the solver fails from the beginning.

Need your advice please.

Thank you

Govind
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Old   January 16, 2014, 09:11
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Lance
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Pulsatile flow and it fails at the end of each pulse? Im guessing there is something wrong with your boundary conditions. But since you havent provided us with enough information, that is all I can say...
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Old   January 16, 2014, 21:51
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Quote:
Originally Posted by Lance View Post
Pulsatile flow and it fails at the end of each pulse? Im guessing there is something wrong with your boundary conditions. But since you havent provided us with enough information, that is all I can say...
I did steady state simulation and then switch to transient.
I use SST turbulence model.

Thanks

Govind
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Old   January 17, 2014, 04:37
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Quote:
Originally Posted by kmgraju View Post
I did steady state simulation and then switch to transient.
I use SST turbulence model.
Thanks
Govind
You'll have to do better than that. Have you read Before you post a question please read this ?
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Originally Posted by ghorrocks View Post
Include enough detail in your question. Put pictures in your post to describe what you mean, include the CCL file and/or the output file and fully describe what you are trying to do. If we don't know what you want to do it will be hard for us to help.

Remember, nobody is paid to answer questions on this forum. People answer questions because they like to help people so help yourself by posting a well written, thought out and interesting question. You will get a much better response that way!
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