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-   -   Fluent Convergence Problems (https://www.cfd-online.com/Forums/fluent/41650-fluent-convergence-problems.html)

Jason July 13, 2006 14:28

Re: Fluent Convergence Problems
 
For the mesh pics, I'm trying to see why you have so many elements in the cylinders (where the flow should be pretty straight forward) and so few near the valve (where the flow will be pretty complex if I remember your valve correctly). So I'm thinking the TGrid pics would be good. Anything that gives me a reasonable idea of what your mesh is like.

Send them to my yahoo e-mail... (I'm still using jason_at_bae). I should be able to check it later tonight.

Thanks, Jason

Vidya July 13, 2006 15:02

Re: Fluent Convergence Problems
 
Jason,

I just sent you the e-mail.

Thanks, Vidya

Vidya July 17, 2006 08:02

Re: Fluent Convergence Problems
 
Hi Jason,

I'm still getting the floating point error in my unsteady case and it looks like this time too the computation will go on forever. The residual for continuity is rising steeply and now after 154 iterations has reached 3e+17 and is continuing to increase. hat may be the cause for this?

Thanks, Vidya


Jaiganesh S November 5, 2012 08:09

Error: Divergence detected in AMG solver: x-momentum
 
Hi everyone,

I am doing Aeroacoustic analysis on aircraft wing using Ansys fluent. After 53 iterations, it getting error. I mentioned that error below.

Error: Divergence detected in AMG solver: x-momentum.

I have described about my case below.
Pressure based, Transient.
LES Model.
Velocity Inlet , pressure outlet.
Scheme- PISO, neighbor correction - 1, Pressure - standard, momentum - Bounded central differencing, Transient formulation- First order Implicit, non iterative time advancement.
URF for Pressure - 0.001, for Momentum - 0.004.

And also I used Outflow as outlet instead of Pressure outlet. I changed neighbour correction & under relaxation factor. These Changes are not working.

Grid quality details:
Max. cell squish= 9.23091e-001.
Max. aspect ratio = 3.22832e+002.

Kindly help me to solve this problem. I am waiting for your kind response.

Thank you.

hiteshlande January 1, 2016 13:01

Hello All

I am doing mesh independence study for transient case.Where there is modification of mesh there is sudden shoot in temperature above 5000 k. Can any1 tell me the reason for this?
Thank you....


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