[Ahmed Alkaisi]

Dear Sir/ Madam,
I need your assistance, please.
I see the following error message after run calculation of ANSYS-Fluent.

“Divergence detected in AMG solver: temperature”

How can I overcome this problem, please?
Regards,
Ahmed Alkaisi

[Kimia]

Originally Posted by Ahmed Alkaisi

Dear Sir/ Madam,
I need your assistance, please.
I see the following error message after run calculation of ANSYS-Fluent.

“Divergence detected in AMG solver: temperature”

How can I overcome this problem, please?
Regards,
Ahmed Alkaisi

In my experience, when you get this error you should check for several things. many things can cause this error.

1) check for all the boundary conditions and models to be set correctly
2) disable the energy equation to see if the model converges without energy equation
3) Decrease under relaxation factors
4) Use transient with smalll time step
5) check your mesh and the quality of the mesh to be reseonable

[Ahmed Alkaisi]

Originally Posted by Kimia

In my experience, when you get this error you should check for several things. many things can cause this error.

1) check for all the boundary conditions and models to be set correctly
2) disable the energy equation to see if the model converges without energy equation
3) Decrease under relaxation factors
4) Use transient with smalll time step
5) check your mesh and the quality of the mesh to be reseonable

Thank you very much, Kimia
I work on fluent solver
I have transient multiphase VOF with solar ray tracing
some friends told me to check the temperature limit from solution control
according to your answers
what is the minimum value of relaxation factor (I used 0.75)
what is the smallest time step (I used 30 seconds)
Please advise
Regards

[Kimia]

Originally Posted by Ahmed Alkaisi

Thank you very much, Kimia
I work on fluent solver
I have transient multiphase VOF with solar ray tracing
some friends told me to check the temperature limit from solution control
according to your answers
what is the minimum value of relaxation factor (I used 0.75)
what is the smallest time step (I used 30 seconds)
Please advise
Regards

You're welcome.
I am not an expert in this. but when I have divergence I usually start with under relaxation factors around 0.01 and then 0.1 to see what happens. For time step I use 1e-05 or even smaller.

There is a discussion topic on this, You can check it out:

http://www.cfd-online.com/Forums/flu...mperature.html

Good luck.

[Ahmed Alkaisi]

Thank you very much
All the best for you