topic Re: Convergence Issues in Simulation in Fusion Design, Validate & Document Forum

Convergence Issues in Simulation

SlawsonEngineering — Mon, 03 Apr 2017 20:58:17 GMT

I have a model in which I solved with a certain load. Convergence plot shows good, 3%, under the target of 5%. Next I used the same load and mesh settings, only changed the direction of the load, and now the mesh won't converge. I will only get to 35%. Any ideas on why this might be?

Re: Convergence Issues in Simulation

Mike.Grau — Tue, 04 Apr 2017 07:31:31 GMT

Hi @SlawsonEngineering

Sorry, this was a duplicated post.

Thanks,

Re: Convergence Issues in Simulation

Mike.Grau — Tue, 04 Apr 2017 07:30:42 GMT

Hi @SlawsonEngineering

Thank you for your post in the Forum.

I would be happy to review your simulation setup and help you to troubleshoot the error.

It would be great if you could share your design with me.

Could you share a "Public Link" of your design via "Private Message"

If you would like to know how to

Share the design via "Public Link", please review the article Here
Download Screencast for your Operating System, please use this article Here
Create a Screencast to share a video of your workflow with the link Link Here

Please, keep me updated.

Thanks,

Re: Convergence Issues in Simulation

Mike.Grau — Mon, 10 Apr 2017 14:42:11 GMT

Hi @SlawsonEngineering,

Please, let us know if the change load and constraints have been helpful

solve the error with the unresolved Stiffness Matrix.

Thank you and best regards,

Re: Convergence Issues in Simulation

SlawsonEngineering — Mon, 10 Apr 2017 23:09:44 GMT

Mike,

I understand what you did by changing the boundary conditions to change the stiffness matrix, but I don't understand why improved convergence. Can you please explain further?

Re: Convergence Issues in Simulation

Mike.Grau — Tue, 11 Apr 2017 07:55:17 GMT

Hi @SlawsonEngineering,

Thank you for asking about that. Yes, you have seen that, right.

I did not do anything to control the convergence of the results, since you have selected "Automatic Adaptive Mesh Refinement"

and the automatic convergence looked actually great.

If you would like to have more control over the convergence, you can play with number of adaptive mesh refinement steps within the Settings.

You would un-check the box and play with the "Results Convergence Tolerance" and the "Portion of Elements to Refine".

Just in case you do not reach convergence on a lower tolerance, you may want to increase the "Maximum Number of Mesh Refinements"

This link here in our learning content gives you a great overview how to work with the Settings in Fusion 360.

I hope this answers your question. Please, keep me updated.

Thank you,