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-   -   Error: Divergence detected in AMG solver: x-momentum (https://www.cfd-online.com/Forums/fluent/108641-error-divergence-detected-amg-solver-x-momentum.html)

Vidyanand Kesti September 26, 2013 05:50

if you rae using FLUENT can you convert to ploy and try may be you can avoiad this
Mesh-ployhydrel-convert domain
or smooth and swap

dinesh September 26, 2013 09:09

Quote:

Originally Posted by ghost82 (Post 453656)
You must assign X as the axisymmetric axis.

Daniele

thank-you sir

Is there a method where i can change my Y axis to X axis. So that i dont have to make it again? Even if it is possible in workbench please let me know?

ghost82 September 26, 2013 09:19

Quote:

Originally Posted by dinesh (Post 453725)
thank-you sir

Is there a method where i can change my Y axis to X axis. So that i dont have to make it again? Even if it is possible in workbench please let me know?

I think you have to go back to pre processing and rotate/translate geometry+mesh.

Daniele

A CFD free user September 29, 2013 15:29

Quote:

Originally Posted by niloogh (Post 429632)
hi Daniele
is taking x axis as axisymmetric needed in 3D too???

Hi Friend
As far as I know, there's no necessity for 3d geometry to define x axis as axisymmetric B.C.
Good luck

ryujibando September 30, 2013 01:06

need help
 
Hello my name is aan. Now I'm doing project about combustion zone in secondary reformer of ammonia plant. Can anyone check mesh generated in my project? I really appreciate if there is someone who would like to discuss with me.

Best regards,

AAN

samir_cfd March 28, 2014 10:04

Good day
I have a problem when I am simulate unsteady flow around a propeller, divergence detected in amg solver. x momentum, I reduce the URF but is the same problem

neprendo March 29, 2014 11:33

Its probably an issue with your boundary conditions and/or mesh then. Double check your BCs, refine your mesh and put the URFs back to the defaults. The default URFs with make your solution converge quicker.

Nick

abhijithmohan March 30, 2014 22:15

try changing the mesh and relaxation factor

chrischensong April 9, 2014 03:44

Quote:

Originally Posted by niloogh (Post 442621)
hi dear
my problem was related to the periodic boundaries.after changing some things in gambit ;i had solved my problem.if your problem has periodic boundaries i,ll explan it in details for you.

Hi niloogh,

I got a similar problem now. I added a udf velocity profile at the inlet of a pipe and the domain is only quarter of real geometry with periodic boundary condition. I have tried all the ways that mentioned above but the error message still comes out every time "Divergence detected in AMG solver". Could you tell me that how did you solve your problem with the periodic bcs?

Thanks
Chris

shrav April 16, 2014 18:44

Quote:

Originally Posted by niloogh (Post 442621)
hi dear
my problem was related to the periodic boundaries.after changing some things in gambit ;i had solved my problem.if your problem has periodic boundaries i,ll explan it in details for you.

I have periodic boundaries in my model and i am facing the same error - divergence in the AMG solver x momentum. Can you plz explain how u solved ur problem

noorul May 27, 2014 07:01

Quote:

Originally Posted by ghost82 (Post 453656)
You must assign X as the axisymmetric axis.

Daniele

how to set the direction of axis symmetric flow?

ghost82 May 27, 2014 08:43

It must be done in pre processing

Triality November 29, 2015 04:14

Hi Marion , im facing the same problem . Mine calculation popped out error after run a certain number of iterations, any solution to it ? Thanks in advance .

yanan-0124 April 13, 2016 10:10

Quote:

Originally Posted by cfd seeker (Post 389146)
Reduce the under relaxation factors

hello ,i am doing the water injection into the air.And i am faced with the same problem ( Divergence detected in AMG solver: x-momentum ).Because my mesh is 3-D, i am confused about the symmetry .
thank you in advance !!


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