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.

Modeling Friction

Please login with a confirmed email address before reporting spam

Hello,

I am trying to model a Ti-alloy interlocked diamond in compression. As part of the model, I would like to add the friction between the diamond and a "steel plate", which I made into a rigid body to help with convergence. When I try to run the model with friction, I get the atttached error. I also attached a picture of how I set up the friction. Please let me know any additional information needed to help the model converge.

Thank you! Danny



1 Reply Last Post 20.07.2020, 22:54 GMT-4

Please login with a confirmed email address before reporting spam

Posted: 4 years ago 20.07.2020, 22:54 GMT-4

I wanted to add more information to better help with getting some ideas. I attached a picture of the model. There is a contact pair between the steel block and the alumide diamond. The steel block is a fixed rigid body.

The alumide interlocked diamond is fixed on the bottom leg that is not part of the contact pair. The top legs have a downward vertical displacement of 1 mm (~10% total length) applied as a ramp function in .04 increments from 0 to 1.

I have seen issues with both plasticity and friction; the friction will not initialize, and the plasticity seems to fail once it enters the yield stress. I know both the friction and plasticity functions have a decent amount of non-linearities. Are there any suggestions to get the model to approach convergence? The model will converge if neither friction nor plasticity are implemented.

Thanks! Danny

I wanted to add more information to better help with getting some ideas. I attached a picture of the model. There is a contact pair between the steel block and the alumide diamond. The steel block is a fixed rigid body. The alumide interlocked diamond is fixed on the bottom leg that is not part of the contact pair. The top legs have a downward vertical displacement of 1 mm (~10% total length) applied as a ramp function in .04 increments from 0 to 1. I have seen issues with both plasticity and friction; the friction will not initialize, and the plasticity seems to fail once it enters the yield stress. I know both the friction and plasticity functions have a decent amount of non-linearities. Are there any suggestions to get the model to approach convergence? The model will converge if neither friction nor plasticity are implemented. Thanks! Danny

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.