Menu

Discussion Forum

New Discussion
查找

Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.

Confusing error message for: Rollers on a beam.

Posted 2022年12月7日 GMT-5 05:14 Studies & Solvers, Structural Mechanics Version 5.6 3 Replies

Amber Labuz
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Hey,

I am creating a model of how a bone will react under different loads from a 4-point bending. The model has been created as a 2D model where the geometry and material properties are set to that of the bone, and the model works when the ends are fixed constraints. I am solving the problem in solid mechanics as a stationery study where the solution is solved using a parametric sweep.

However, I want to change the fixed constraints to roller, as I am validating the model using a 4-pont bending in a lab where the moulded ends are on rollers. When I set the ends of the rectangle to be on rollers in comsol the following error message appear:

Feature: Stationary Solver 1 (soll/s1) Failed to find a solution. The relative residual (0.0093) is greater than the relative tolerance. There was a warning message from the linear solver. Iterative refinement triggered. The returned solution is not converged. Not all parameter steps returned.

Does anyone know how I can solve this problem? I have attached the model below and am hoping someone could explain how to fix it.

Thank you in advance!

Attachments:

3 Replies Last Post 2022年12月12日 GMT-5 11:28
Kristian Rye Jensen COMSOL Employee

Please login with a confirmed email address before reporting spam

Posted: 2 years ago 2022年12月7日 GMT-5 05:25

Dear Amber Labuz,

Thank you for posting on the Discussion Forum.

When you have a roller condition instead of a fixed condition and you have a load, there are nothing to stop the movement, so it will go on indefinitely in the y-direction.

There will be an infinity of solutions, that's why it doesn't converge.

If you have further questions, you can use the technical support through support@comsol.com.

Hope this helps.

Best regards,

Kristian Rye Jensen

-------------------
Kristian Rye Jensen
COMSOL DK
Dear Amber Labuz, Thank you for posting on the Discussion Forum. When you have a roller condition instead of a fixed condition and you have a load, there are nothing to stop the movement, so it will go on indefinitely in the y-direction. There will be an infinity of solutions, that's why it doesn't converge. If you have further questions, you can use the technical support through support@comsol.com. Hope this helps. Best regards, Kristian Rye Jensen
Amber Labuz
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 2 years ago 2022年12月12日 GMT-5 11:19

Hey Kristian,

Thank you for the reply, i have tried contacting the support email but have not gotten any reply. Is there another way i can add mechincal support rollers onto my model?

Best Amber

Hey Kristian, Thank you for the reply, i have tried contacting the support email but have not gotten any reply. Is there another way i can add mechincal support rollers onto my model? Best Amber
Jeff Hiller COMSOL Employee

Please login with a confirmed email address before reporting spam

Posted: 2 years ago 2022年12月12日 GMT-5 11:28

Hello Amber,

The support team sent you a response on December 9 (three days ago). Please check your Access account / email.

Best,

Jeff

-------------------
Jeff Hiller
Hello Amber, The support team sent you a response on December 9 (three days ago). Please check your Access account / email. Best, Jeff

Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.

Suggested Content