CFD Online Discussion Forums - Linear solver fails only in the last iteration

CFD Online Discussion Forums (https://www.cfd-online.com/Forums/)

- CFX (https://www.cfd-online.com/Forums/cfx/)

- - Linear solver fails only in the last iteration (https://www.cfd-online.com/Forums/cfx/128591-linear-solver-fails-only-last-iteration.html)

Linear solver fails only in the last iteration

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

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...

Quote:

Originally Posted by Lance (Post 470313)

I did steady state simulation and then switch to transient.
I use SST turbulence model.

Thanks

Govind

Quote:

Originally Posted by kmgraju (Post 470431)

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 http://www.cfd-online.com/Forums/cfx...ease-read.html ?

Quote:

Originally Posted by ghorrocks (Post 221975)

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!