Learning Forum

[Agung Limowa]

I desperately need your help with this Ansys Fluent. I have problem  with Floating point exceeded and it give me error every time. I tried to remeshing (the change insignificant because its a large model eith quite complex shape), reducing timestep but it's always the same. Is there because of memory issue? because i run it on core i7 16 gb ram with 13m cells ? or it might be something else

 

Console Error :

eversed flow on 36 faces (51.9% area) of pressure-outlet 18.

 

Reversed flow on 29 faces (47.1% area) of pressure-outlet 19.

Stabilizing k to enhance linear solver robustness.

Stabilizing k using GMRES to enhance linear solver robustness.

 

Divergence detected in AMG solver: k Stabilizing omega to enhance linear solver robustness.

Stabilizing omega using GMRES to enhance linear solver robustness.

 

Divergence detected in AMG solver: omega Stabilizing temperature to enhance linear solver robustness.

Stabilizing temperature using GMRES to enhance linear solver robustness.

 

Divergence detected in AMG solver: temperature

Error at host: floating point exception

[Federico Alzamora Previtali]

 

Hello, 

divergence of solution could be caused by several reasons and requires context. I would start by looking at your mesh: what is your mesh quality?

 

[Agung Limowa]

 

Here the orthogonal quality, and i think it not bad and there's no problem with the mesh, anything else seem to be a problem ?

[Federico Alzamora Previtali]

It's hard to tell from your screenshot, but there might be a few cells that are not of good quality. In your Outline in Meshing, click on Mesh > Quality. What are the Min/Max values for Orthogonal Quality? What about Skewness?

Alternatively, if you do a Mesh Quality check in Fluent, what is the reported Minimum Orthogonal Quality? 

[Agung Limowa]

Minimum Orthogonal Quality =  2.78873e-02 cell 13071450 on zone 11 (ID: 633131 on partition: 0) at location ( 3.35651e+01, -1.35942e+01, -1.52944e+02)

Maximum Aspect Ratio =  9.38575e+01 cell 9828862 on zone 11 (ID: 13076063 on partition: 0) at location ( 3.24330e+02, -4.71526e+01, -2.76560e+02)

 

[Agung Limowa]

There is my result of the quality check on fluent, I've done several method and mesh pattern but the mesh quality changes is insignificant

 

[Federico Alzamora Previtali]

Minimum Orthogonal Quality of 0.02 seems low to me and can results in problems, such as the ones that you are facing. We typically recommend at least 0.1 for minimum orthogonal quality. Have you tried meshing using Fluent Meshing? We have workflows that streamline and simplify the meshing process. Mesh Generation using Ansys Fluent Meshing | Ansys Courses