Learning Forum

[marcelozortea]

Hi everyone,

 

I'm trying reproduce this video:

 https://www.youtube.com/watch?v=_4FLYk00mls

 

There is only one difference between the video simulation and my simulation the geometry, but I think that there aren't problem with it

 

However when I solve the Transient Thermal Analysis I recieve this error:

I read the discussions:

/forum/forums/topic/solver-pivot-warning/

/forum/forums/topic/a-solver-pivot-warning-or-error-has-been-detected/

but neither one helped me

 

 

[peteroznewman]

Methods to resolve a solver pivot warning in a Structural model are different from what is needed to resolve the problem in a thermal model.

I have much less experience with thermal troubleshooting than structural, but if you attach a .wbpz archive file, I will take a look.

[marcelozortea]

Peter I don't know how to attach on ansys community, I tried click on attach but did not happen anything, I'll post at my google drive and share to public, I hope that aren't any problems...

you can download it by: https://drive.google.com/open?id=1OF741z5A6vNWx8rOla1_ygMiy7rqJ1kQ

[peteroznewman]

Marcelo, I downloaded your model and made some changes to allow it to converge.

I'm not certain, but I don't think it is valid to put both a Heat Flow and a Convection Boundary Condition on the same face.  I separated them.

I also made sure there were many elements through the thickness

I also turned on Automatic Time Stepping and used a small Initial Time Step

Finally, I reduced the size of the Heat in each step and changed the Convection Coefficient.

I you can try various changes to return it to what you wanted and find out which change breaks the model.

Attached is a 2020 R1 archive.

 

[hosseinfakhraie]

http://s7.picofile.com/file/8389337018/stress_belt.rar.html 

http://s6.picofile.com/file/8389337200/solid_pully.rar.html

Hi, i´m working on a project that is necessary to get the stress of a belt, but occurs this error:

"1.       Not enough constraints appear to be applied to prevent rigid body motion. This may lead to solution warnings or errors. Check results carefully

 

Solver pivot warnings or errors has been encountered during the solution. This is usually a result of an ill conditioned matrix possibly due to unreasonable material properties, an under constrained model, or contact related issues. Check results carefully."

What I can do to fix it?

[peteroznewman]

@hosseinfakhraie, when a discussion is Solved, as shown by the big green tick mark, members stop looking at it.

You should start a New Discussion that you will own and you can mark it as Solved when you get an answer.